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FIRE SERVICE AND GENERAL FIRE SAFETY TOPICS => Technical Advice => Topic started by: Benzerari on September 30, 2008, 10:06:34 PM
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Guys;
For some reasons we are required to re-calculate the FAS's load, in every service visit, and see if the batteries are still reliable, to support feeding the FAS in quiscent and alarm conditions...etc
The formula is the following:
C = [ I1 . T1 + I2 . T2 . D ] 1,25
Where:
C: is the batteries capacity
I1: is the load’s quiescent current
T1: is the stand by time (while mains disconnected) = 48h
I2: is the load’s alarm current
T2: is the minimum alarm time (while mains disconnected) = 0.5h
1.25: is further safety coefficient of tolerance for the batteries capacity
D: is de-rating factor = ‘2’ and this is my main concern!
What is de-rating factor? and Why it’s set to ‘2’?
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Benz,
The de-rating factor recommendation in BS5839 part 1 2002 is actually 1 or 1.75 and not 2.
It is 1 when the system alarm load is equal or less than 1/20th of the battery's stated capacity. It is 1.75 when the battery's alarm load is greater than 1/20th of the battery's staed capacity.
BS recommends that you check any de-rating factor to be used from the actual battery manufacturers literature. If none is available, you should use the figure 1.75.
Using a de-rating factor in your calculations provides a calaculation as taking into account of the fact that the battery's stated capacity in AH is a nominal figure because most batteries can't actaully meet their capacity rating on high loads and are likely to exceed it on low loads. I.e a 24AH would probably be able to provide 1A for 30 hours but only 8 hours at 2.4A. The battery capacity is normally rated as if 1/20th is being taken out of it i.e if 1.2A was taken from a 24AH battery it would last 20 hours (i.e what you would expect from a 24AH battery!)
In respect of the BS formula, I know that you, Benz, can cope with formula math because I've noticed that you quote it quite often in your posts. Not everyone is as proficient, and the formula shown in BS i.e. 1.25(T1 I1 + D I2/2) fazes many people.
In trying to calculate the likely duty of the battery in an installed system, there is a simpler way of making a good calculation.
At the end of the day, you are trying to prove that the installed battery capacity is sufficient for the system load and you want to know how many hours standby the battery can provide (normally 24 hours in L installations).
The Fire Alarm Wizard's own method and calculation of doing this is carried out as follows:
1) Determine the system batterys' rated capacity in AH by reading what is printed on the battery.
2) Convert that figure into mAH by multiplying by 1000. i.e a 7AH battery becomes 7000mAH
3) Take 75% of the figure calculated in 3 above ( i.e. 75% of 7000mAH is 5250mAH) This figure (5250 in this example) becomes the new available battery capacity to be used in further calculation.
4) Take readings of both the standby load (in mA) and alarm load (in mA) of the systems *. For our example we will assume that our readings give a standby load of 70mA and an alarm load of 200mA
5) We now deduct half the alarm load reading from the battery capacity figure (we use a reading of half because the alarm load only has to operate for 30 mins). In our calculation this would be 5250 - 100 = 5150. This figure of 5150 becomes the new available battery capacity figure to be used in further calculation.
6) Divide the standby load reading into available battery capacity figure. In our calculation this would be 5150/70 = 73.57
7) The figure of 73.75 now equates to the number of hours standby duty available in our battery whilst still providing sufficient capacity to sound the full alarm load for 30 minutes and assuming our battery only has 75% of it's rated capacity.
* The practical method of calculating standby and alarm loads is to connect a ampmeter (reading mA) in series with the battery connection of the control panel/power supply. Disconnect the mains supply to the control panel and then take the standby load reading. Then initiate a full fire condition and then take the alarm load reading.
I hope you will agree that the above is the simplest practical method for an engineer on site to calculate the available standby capacity of battery in hours of any installed system and turns the BS 5839 formula into a set of practical and simply understood steps. Please note however that this method and calculation does not factor in any battery de-rating factor. I have never included the de-rating factor into my method because a) The de-rating figure is often 1 and therefore has no effect on the calculation and b) because it adds a further step to the calculation that blow's most fire aalrm engineer's minds! You could probably cope with it and adjust Wiz's on-site calculation method and include it.
I have tested my method over many years of use and have patents pending on it ;)
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Benz,
The de-rating factor recommendation in BS5839 part 1 2002 is actually 1 or 1.75 and not 2.
It is 1 when the system alarm load is equal or less than 1/20th of the battery's stated capacity. It is 1.75 when the battery's alarm load is greater than 1/20th of the battery's staed capacity.
BS recommends that you check any de-rating factor to be used from the actual battery manufacturers literature. If none is available, you should use the figure 1.75.
Using a de-rating factor in your calculations provides a calaculation as taking into account of the fact that the battery's stated capacity in AH is a nominal figure because most batteries can't actaully meet their capacity rating on high loads and are likely to exceed it on low loads. I.e a 24AH would probably be able to provide 1A for 30 hours but only 8 hours at 2.4A. The battery capacity is normally rated as if 1/20th is being taken out of it i.e if 1.2A was taken from a 24AH battery it would last 20 hours (i.e what you would expect from a 24AH battery!)
In respect of the BS formula, I know that you, Benz, can cope with formula math because I've noticed that you quote it quite often in your posts. Not everyone is as proficient, and the formula shown in BS i.e. 1.25(T1 I1 + D I2/2) fazes many people.
In trying to calculate the likely duty of the battery in an installed system, there is a simpler way of making a good calculation.
At the end of the day, you are trying to prove that the installed battery capacity is sufficient for the system load and you want to know how many hours standby the battery can provide (normally 24 hours in L installations).
The Fire Alarm Wizard's own method and calculation of doing this is carried out as follows:
1) Determine the system batterys' rated capacity in AH by reading what is printed on the battery.
2) Convert that figure into mAH by multiplying by 1000. i.e a 7AH battery becomes 7000mAH
3) Take 75% of the figure calculated in 3 above ( i.e. 75% of 7000mAH is 5250mAH) This figure (5250 in this example) becomes the new available battery capacity to be used in further calculation.
4) Take readings of both the standby load (in mA) and alarm load (in mA) of the systems *. For our example we will assume that our readings give a standby load of 70mA and an alarm load of 200mA
5) We now deduct half the alarm load reading from the battery capacity figure (we use a reading of half because the alarm load only has to operate for 30 mins). In our calculation this would be 5250 - 100 = 5150. This figure of 5150 becomes the new available battery capacity figure to be used in further calculation.
6) Divide the standby load reading into available battery capacity figure. In our calculation this would be 5150/70 = 73.57
7) The figure of 73.75 now equates to the number of hours standby duty available in our battery whilst still providing sufficient capacity to sound the full alarm load for 30 minutes and assuming our battery only has 75% of it's rated capacity.
* The practical method of calculating standby and alarm loads is to connect a ampmeter (reading mA) in series with the battery connection of the control panel/power supply. Disconnect the mains supply to the control panel and then take the standby load reading. Then initiate a full fire condition and then take the alarm load reading.
I hope you will agree that the above is the simplest practical method for an engineer on site to calculate the available standby capacity of battery in hours of any installed system and turns the BS 5839 formula into a set of practical and simply understood steps. Please note however that this method and calculation does not factor in any battery de-rating factor. I have never included the de-rating factor into my method because a) The de-rating figure is often 1 and therefore has no effect on the calculation and b) because it adds a further step to the calculation that blow's most fire aalrm engineer's minds! You could probably cope with it and adjust Wiz's on-site calculation method and include it.
I have tested my method over many years of use and have patents pending on it ;)
Wiz;
Thanks for this good technical answer. The de-rating set to 2 is not my set, it is in the BFPSA (FIA) books, I myself haven't understood the de-rating factor since I had done BFPSA courses sometimes ago..., and thank you again for this technical answer.
The load’s currents I1 and I2 required in each service visit (for some reasons) are NOT the theory ones you get usually through batteries calculations for first install, while taking into account the individual current consumption of each device..., I1 and I2 are the actual and practical measurements of the full load, while fitting the Amp-meter in serial with the batteries, while mains disconnected, also in both quiescent and alarm conditions. And they could be different to the theory values for some reason or other.
Any way your answer does make many senses, thank you
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Wiz;
Thanks for this good technical answer. The de-rating set to 2 is not my set, it is in the BFPSA (FIA) books, I myself haven't understood the de-rating factor since I had done BFPSA courses sometimes ago..., and thank you again for this technical answer.
The load’s currents I1 and I2 required in each service visit (for some reasons) are NOT the theory ones you get usually through batteries calculations for first install, while taking into account the individual current consumption of each device..., I1 and I2 are the actual and practical measurements of the full load, while fitting the Amp-meter in serial with the batteries, while mains disconnected, also in both quiescent and alarm conditions. And they could be different to the theory values for some reason or other.
Any way your answer does make many senses, thank you
Benz... you should always check I1 ans I2 on commissioning to see if they tally with the theoretical calculations.
The figures should always be checked on a service visit also as it could be an indication part of the system is drawing more current than it should and requires investigation.
We have also had instances in the past where tenants organise their own fitouts and and fims just add detection and sounders as they feel like it to a particular area in a building. By checking the quiescent and the load each visit we know if someone has been adding things they shouldn't.
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Wiz;
Thanks for this good technical answer. The de-rating set to 2 is not my set, it is in the BFPSA (FIA) books, I myself haven't understood the de-rating factor since I had done BFPSA courses sometimes ago..., and thank you again for this technical answer.
The load’s currents I1 and I2 required in each service visit (for some reasons) are NOT the theory ones you get usually through batteries calculations for first install, while taking into account the individual current consumption of each device..., I1 and I2 are the actual and practical measurements of the full load, while fitting the Amp-meter in serial with the batteries, while mains disconnected, also in both quiescent and alarm conditions. And they could be different to the theory values for some reason or other.
Any way your answer does make many senses, thank you
Benz... you should always check I1 ans I2 on commissioning to see if they tally with the theoretical calculations.
I know that, but I am talking about in every service visit :)
The figures should always be checked on a service visit also as it could be an indication part of the system is drawing more current than it should and requires investigation.
Indeed, this is part of the matter !
We have also had instances in the past where tenants organise their own fitouts and and fims just add detection and sounders as they feel like it to a particular area in a building. By checking the quiescent and the load each visit we know if someone has been adding things they shouldn't.
We have seen the other way round, the customer had some alterations, and the builders cut off a lot of wiring..., when the fire alarm systems went faulty their electrician managed to run some bits of wiring to close the circuits back to normal but not as it was... they had tried to avoid further spending if the alarm company is called for that purpose…
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.......The load’s currents I1 and I2 required in each service visit (for some reasons) are NOT the theory ones you get usually through batteries calculations for first install, while taking into account the individual current consumption of each device..., I1 and I2 are the actual and practical measurements of the full load, while fitting the Amp-meter in serial with the batteries, while mains disconnected, also in both quiescent and alarm conditions. And they could be different to the theory values for some reason or other.........
Benz, What it means is that I1 and I2 should always first be calculated theoretically at design stage by using the number of devices and the cie and their supposed current consumptions for use in the battery capacity requirement calculations.
However, as we know, and David mentions, what you end up with on-site at a later date can be different from what was used in the original design calculations.
This explains your question 'And they could be different to the theory values for some reason or other'.
Therefore the I1 and I2 values should be ascertained on-site each time a battery capacity calculation is required and these used rather than the original 'theoretical' ones.
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....... The de-rating set to 2 is not my set, it is in the BFPSA (FIA) books, I myself haven't understood the de-rating factor since I had done BFPSA courses sometimes ago...,
Benz, the BFPSA de-rating figure of 2 you mention is very interesting. By my calculations of this in the BS capacity calculation formula this would calculate that they assume that the battery is actually half-as-good as the theoretical rating obtained by the capacity descritption i.e a 24AH should be assumed to have only 12AH capacity!
Surely this can't be right?
How do the BFPSA justify this?
Why do the BFPSA think they know better than the BS or rather why do they make recommendations that vary from the BS. Do they think the BS committee don't know what they are doing?
How can they say a de-rating figure of precisely 2 is always right? even the BS states that the any specific de-rating factor for any battery should be ascertained from technical info and in the absence of such, should be considered as 1.75.
I think you should take this up with the BFPSA and if they can't justify their recommendations with proven facts they should be asked why they are messing with BS5839 Part 1.
I'm getting sick of every man and his dog coming up with their own set of recommendations when BS provides a perfectly adequate recommendation. The Fire Services are particularly fond of doing this, particularly in the past, and it makes a mockery of the national/european standards.
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Benz are you sure you haven't got it mixed up....
In order to simplify the calculation the official BFPSA recommended formula is:
BATTERY = 1.25 (T1I1 + I2)
I2 being the alarm load
Mimimum standby time (T1)
Quiescent standby current (I1)
Standby Capacity (T1 + I1)
Load Capacity (T1I1 + I2)
1.25 being an aging factor (25% per year - estimated)
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Benz are you sure you haven't got it mixed up....
In order to simplify the calculation the official BFPSA recommended formula is:
BATTERY = 1.25 (T1I1 + I2)
I2 being the alarm load
Mimimum standby time (T1)
Quiescent standby current (I1)
Standby Capacity (T1 + I1)
Load Capacity (T1I1 + I2)
1.25 being an aging factor (25% per year - estimated)
It is always the same formula!
Indeed when it's simplifyed D = 2 and T2 = 0.5h, hence their product = '1'. As BFPSA sets D = 2 as constante value not like in BS as Wiz mentioned it could be less then '2', 1.75...etc
Threrefore C = (I1 T1 + I2) 1.25
There is no confusion in that
You have stated above, standby capacity is (T1 + I1) I assume it's by mistake, it should be (T1 * I1)
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1.25 being an aging factor (25% per year - estimated)
This is another issue new to me as well, the batteries calculation formula should be then according to the above
1st year of install: C = [I1 T1 + I2 T2 D] 1.25
2nd year of install: C = [I1 T1 + I2 T2 D] 1.50
3rd year of install: C = [I1 T1 + I2 T2 D] 1.75
4rd year of isntall: C = [I1 T1 + I2 T2 D] 2
5rd year of install: C = [I1 T1 + I2 T2 D] 2.25
Is that correct? or am I missinterpreting? :)
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Please note however that this method and calculation does not factor in any battery de-rating factor. I have never included the de-rating factor into my method because a) The de-rating figure is often 1 and therefore has no effect on the calculation and b) because it adds a further step to the calculation that blow's most fire aalrm engineer's minds! You could probably cope with it and adjust Wiz's on-site calculation method and include it.
I have tested my method over many years of use and have patents pending on it ;)
Wiz;
In here, you are against both BFPSA and BS versions, by not considering the de-rating factor...etc :)
What sort of
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David, I agree with Benz - your comment 1.25 being an aging factor (25% per year - estimated) [i/] can't be right. The 1.25 in the formula relates to making a calculation that assumes a 75% battery capacity. But this is not per year. It is a one-off figure suitable for the whole life of the battery.
The second point I'd like to make is regarding the 'simplified formula' that you say the BFPSA recommends. This is the same as the BS recommendation but doesn't include the de-rating factor and the 50% division of the alarm load. On the basis that the BFPSA suggest a de-rating of 2 according to Benzi, then this cancels out the 50% division of the alarm load. So this would be where the simplified formula comes in! - Ignore the derating figure and the division the alarm load because it achieves tha same result - but only if you assume the derating figure is 2!
Some examples:
The last part of the BS formula is DxI/2 where D is the derating figure and I is the alarm load. If the alarm load is 3A and the de-rating figure is 2 (as Benzi says BFPSA suggests) then the calculation is:
2*3/2 = 3
The BFPSA simplified formula that you suggest for the above is just I, which, in our example, is just 3!
i.e. the simplified formula is the same as the BS formula if the de-rating figure is taken to be 2
However, if we use the BS mentioned de-rating figures of 1 or 1.75 we get:
1*3/2= 1.5 or 1.75*3/2= 2.625
I can see why BFPSA might want to use a de-rating figure of 2 to make the formula much simpler. But why should they do this and can they justify the impact this might have on the BS battery calculation.
If BFPSA is going to mess with BS recommendations, how far will they go? I suppose they could even say something like you can ignore installing detectors in large voids, because it can sometimes be difficult to do! Where could it end?
Surely the BFPSA's job should be to ensure BS recommendations are followed and instruct their members in understanding how to comply with them - not to change the BS recommendations to make things easier!
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Please note however that this method and calculation does not factor in any battery de-rating factor. I have never included the de-rating factor into my method because a) The de-rating figure is often 1 and therefore has no effect on the calculation and b) because it adds a further step to the calculation that blow's most fire aalrm engineer's minds! You could probably cope with it and adjust Wiz's on-site calculation method and include it.
I have tested my method over many years of use and have patents pending on it ;)
Wiz;
In here, you are against both BFPSA and BS versions, by not considering the de-rating factor...etc :)
What sort of
Not quite Benz, my method assumes that the derating figure is 1 because the alarm load on most systems I deal with is less than 1/20th of battery capacity. This complies with B.S. ! ;)
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The de-rating factor recommendation in BS5839 part 1 2002 is actually 1 or 1.75 and not 2.
It is 1 when the system alarm load is equal or less than 1/20th of the battery's stated capacity. It is 1.75 when the battery's alarm load is greater than 1/20th of the battery's staed capacity.
According to the above, the de-rating factor is more related to (the batteries capacity per actual load), to keep a nominal supply current value not to its min and not to max…etc
I2 T2/ C <= 1/20, means the system will supply half hour alarm (while mains disconnected) for 20 times or more… is that what is required by BS?
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Please note however that this method and calculation does not factor in any battery de-rating factor. I have never included the de-rating factor into my method because a) The de-rating figure is often 1 and therefore has no effect on the calculation and b) because it adds a further step to the calculation that blow's most fire aalrm engineer's minds! You could probably cope with it and adjust Wiz's on-site calculation method and include it.
I have tested my method over many years of use and have patents pending on it ;)
Wiz;
In here, you are against both BFPSA and BS versions, by not considering the de-rating factor...etc :)
What sort of
Not quite Benz, my method assumes that the derating figure is 1 because the alarm load on most systems I deal with is less than 1/20th of battery capacity. This complies with B.S. ! ;)
I assume it is not particularly the one you deal with, but rather you have decided that your systems will supply 20 times alarm to go off (while mains disconnected) and for half hour each time and no more than 20 times...etc
Also your method is in fact your decision but it still the same method :)
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Also what ever version of batteries calculation formula either original or the simplified one while D=2: my understanding of 1.25 coefficient is NOT the aging factor, it is rather a farther safety tolerance, say if the calculation gives 6Ah are required you always prefer to order a bit further reserve (just in case), it is the same fashion of thought every where in business and engineering... if you need 1000 bricks to build your home you have to order 1100 say 1/10 more bricks...etc
But regarding the batteries aging issue, I would see it from a different angle, I think it's among the main issues why the batteries calculation have to be carried out in each service visit, not only in case the customer has fitted extra devices, rather it's the batteries internal impedance that gets up day to day, even the load has not been changed at all for years, the internal impedance of the batteries can be seen in serial with the load to give an equivalent load value even bigger and this is already taken into account while calculating the batteries capacity with the actual practical measurements of I1 and I2. to see if C is still above 70% of the prescribed 'capacity on the batteries
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Benz
The BFPSA or FIA formula is
C min= I1xT1+I2x1.25
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Benz
The BFPSA or FIA formula is
C min= I1xT1+I2x1.25
No it is: Cmin = [ I1 T1 + I2] 1.25 while D =2 and T2 = 0.5h their product will be simplified to give this formula
you have forgoten this [ .... ] which makes a difference
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BODMAS Graeme!!!
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Ahh, the great mathemeticians remember there school days, and so far back. Blackboard rubbers, sorry, whiteboard erasers being thrown around for not remembering the brackets. Only hurt for a while, well until the next time anyway.
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I am still not sure how BS calculated the de-rating factor to be either 1 or 1.75 also how the BFPSA calculated the de-factor to be = 2?
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Benz
The BFPSA or FIA formula is
C min= I1xT1+I2x1.25
No it is: Cmin = [ I1 T1 + I2] 1.25 while D =2 and T2 = 0.5h their product will be simplified to give this formula
you have forgoten this [ .... ] which makes a difference
well i will ask for my money back for their training course that told to do it that way....
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although annex D of BS5839-1 2202 assumes a D factor of 1.75 the FIA/BFPSA recommends using a D factor of 2,which,whilst making very little difference to the final figure,will greatly simplifybattery calculation because a D of 2 multiplied by a T2(alarm time) of 0.5
will equal 1 and can therefore be ignored
furthermore by leaving the multiplication by 1.25(the ageing factor) until last will simplify the actual workings even more....
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although annex D of BS5839-1 2202 assumes a D factor of 1.75 the FIA/BFPSA recommends using a D factor of 2,which,whilst making very little difference to the final figure,will greatly simplifybattery calculation because a D of 2 multiplied by a T2(alarm time) of 0.5
will equal 1 and can therefore be ignored
furthermore by leaving the multiplication by 1.25(the ageing factor) until last will simplify the actual workings even more....
Hows the brick wall standing up??
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Guys,
The 1.25 figure in the formula is the one that will give you the 75% of the capacity which we are all calling the 'ageing factor' for want of a better name! Multiply, for example, the figure 8 by 1.25 and you get an answer of 10. i.e instead of installing an 8AH battery install instead a 10AH battery to compensate for the 'ageing factor'
The de-rating figure, variously mentioned previously, as 1, 1.75 and 2 is a figure which is meant to adjust for a feature of all batteries where the actual capacity achievable from a battery is dependant on the discharge rate. I have previously mentioned this, but just to summarise; a 10AH cpapcity battery should, in theory, provide 1A for 10 hours or 10A for 1 hour. In fact, batteries normally only give their rated capacity at a discharge rate of 1/20th of their rated capacity. i.e. For a 40AH battery it will give 2A for 20 hours.
Furthermore, if your discharge rate is less than 1/20th, the battery is likely to last longer than the supposed capacity i.e for a 40AH battery it will give 1A for more than 40 Hours. Conversely if the discharge rate is more than 1/20th, the battery is likely to last shorter than the supposed capacity i.e for a 40AH battery it will give 4AH for rather less than 10 hours.
Benz, This 1/20th figure is that which my previous posts mentions and it is not what your answers to me are suggesting. It has nothing to do with expecting the alarm to go off 20 times etc.!
Benz, in answer to your question; the BS de-rating figures of 1 and 1.75 are based on typical batteries. De-rating 1 can be used where the alarm load current is low and thereby taking a small current from the battery (less than 1/20th) so the battery is likely to meet it's rated nominal capacity. Where the alarm load current is high and taking a larger current (more than 1/20th) the battery is unlikely to meet it's rated nominal capacity and the de-rating figure of 1.75 will compensate for this.
Graeme, you make the comment that using a de-rating figure of 2 instead of, say, 1,75, will make very little difference. I absolutely agree. However there is a difference. And this difference will be even larger if the de-rating figure should only have been 1.
I understand the BFPSA suggestion of always using a de-rating figure of 2 because this simplifies the formula. It allows the de-rating figure to cancel out the 50% division of the alarm load. Therefore the simplified formula doesn't even mention the de-rating figure (of 2) they have used. However, all of you who have taken the course mention a de-rating figure of 2 and the simplified formula, when the formula has already taken a de-rating figure of 2 into account. It seems to me that this aspect of the simplified formula has not been properly explained on the course.
However, I have strong opinions on the right of the BFPSA to suggest a formula, that whilst easier to use, does not tie in with the recommendations of BS. In fact, I have strong opinions on anyone who varies the recommendations of BS without making sure the impact of doing so is fully understood and explained.
In the case of this battery capacity calculation, I have already admitted that a de-rating figure of 2 against 1.75 is a small difference. But what happens when you calculate using the BFPSA simplified formula that a standby battery will only last 23 hours and fail a system on commissioning, when the system designer has designed used the correct de-rating figure for that battery/system of say, 1, and this provides a battery standby duty of 25 hours? What if the discussion got legal, what would the judge accept? The BS recommendation or the BFPSA's version?
Is it right to follow the BFPSA training if it varies from BS unless the BFPSA highlights those things they have unilaterally changed and explained the potential ramifications?
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Guys,
Benz, This 1/20th figure is that which my previous posts mentions and it is not what your answers to me are suggesting. It has nothing to do with expecting the alarm to go off 20 times etc.!
And
It is 1 when the system alarm load is equal or less than 1/20th of the battery's stated capacity. It is 1.75 when the battery's alarm load is greater than 1/20th of the battery's staed capacity.
Let's formulate what you have stated previously:
If: [(I2 * T2) / C] <= 1/20. This means the batteries are capable of setting alarm off 20 times for half hour each time, or 10 hours continually (while mains disconnected). Therefore: D would equate to 1.
Since: (I2 * T2) is batteries capacity required to set alarm off for 0.5h, and
'C' is the full prescribed battery capacity
If: (I2 * T2) / C > 1/20. This means the batteries are NOT capable of setting alarm off 20 times for half hour each time, or 10 hours continually (while mains disconnected). And therefore to compensate that you said BS sets D = 1.75, but BFPSA sets it to 2. In my opinion NOT to simplify the calculation but for further safety measures
This is my interpretation to what you have stated in your post.
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Guys,
Is it right to follow the BFPSA training if it varies from BS unless the BFPSA highlights those things they have unilaterally changed and explained the potential ramifications?
In my understanding de-rating = 2 of BFPSA is not against in any way the de-rating = 1.75 of BS, with D = 2 it gives the end result a bit more higher:
C1 = C of BFPSA when using D=2
C2 = C of BS when using D=1.75
C1 / C2 = {[I1T1 + I2T2D1] 1.25} / {[I1T1 + I2T2D2] 1.25}
= [I1T1 + I2*0.5 *2] / [I1T1 + I2*0.5*1.75]
= [I1T1 + I2*1h] / [I1T1 + I2*0.855]
If I1 = 20mA,
and I2 = 200mA
Then:
C1 / C2 = [20mA*48h + 200mAh] / [20mA*48h + 200*0.855]
= [96mAh + 200mAh] / [96mAh + 200mAh]
= 296mAh / 171mAh
= 1.73
Therefore: C1 = 1.73 * C2, to me this is considerable difference but to the positive side, D = 2 is just more safer de-rating factor, but it does not mean it's wrong or against BS
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To my understanding I would use D accordingly:
I would use (D = 2) if the system is nearly fully loaded and to be over loaded soon with the time, by means say nearly 120 devices per each loop and nearly the full number of conventional sounders permitted in the sounder circuit...etc
And I would use D = 1.75, if the fire alarm systems is using 50% of the load permitted, by means say 60 devices in each loop and half the number permitted of output conventional devices in the sounder circuits...etc
And I may use D = 1, if the system is not really fully loaded say 20 devices in each loop and very few output conventional devices in the sounder circuits...etc
My timer has timed out now :)
Thank you
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One of the major issues behind the need to get batteries calculation in every service visit is, the temperature impact on the batteries life cycle, according to 'Arrhenius’ equation (Findings), For every 10 °C increase in temperature the reaction rate doubles. Therefore, an hour at 35 °C is roughly equivalent in battery life to two hours at 25 °C. In one side we can say the heat is the enemy of the battery and according to ‘Arrhenius’ even small increases in temperature will have a major influence on battery life cycle affecting both the desired and undesired chemical reactions.
The following figure explains this:
(http://i472.photobucket.com/albums/rr87/BenzFerari/BattTemp.jpg)
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One of the major issues behind the need to get batteries calculation in every service visit is, the temperature impact on the batteries life cycle, according to 'Arrhenius’ equation (Findings), For every 10 °C increase in temperature the reaction rate doubles. Therefore, an hour at 35 °C is roughly equivalent in battery life to two hours at 25 °C. In one side we can say the heat is the enemy of the battery and according to ‘Arrhenius’ even small increases in temperature will have a major influence on battery life cycle affecting both the desired and undesired chemical reactions.
The following figure explains this:
http://i472.photobucket.com/albums/rr87/BenzFerari/BattTemp.jpg
Benz - without trying to appear rude you have a tendancy to overcomplicate and go into too much detail on what are simple enough topics.
If the BS says use this calculation then I use it and if it is wrong for some reason then that's not my fault - I calculated to the formula given by BS5839!
Some of us are but mere fire alarm engineers!!
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Hear, hear Buzz !,
Benz, you are not quite getting it. It is probably a failure of my explanation, but I can't do much more. My old shrivelled wizard's brain is failing.
But just a couple of points:
The de-rating figure is to compensate for features of the battery and not of the system. However, the compensation for the battery is adjusted by features of the system. Your previous post explains the circumstances when you would use a de-rating figure of 1 or 1.75. These circumstances are not in the BS recommendation.
Have you ever considered doing what BS recommends instead of what you think is right? It might save you grief in the future.
With respect to your comment in yesterday's post ....but to the positive side, D = 2 is just more safer de-rating factor, but it does not mean it's wrong or against BS; I agree a de-rating figure of 2 could be considered 'safer' than a de-rating figure of 1, because you just end up with a higher capacity standby battery. However BS doesn't recommend a catch-all de-rating figure of 2. So by using that figure in that way, it is clearly going against the recommendations of BS. You will end up with a bigger battery than you might otherwise need to meet BS recomendations.
More importantly, sometime in the future, when you commission a system designed by me and you use the catch-all de-rating figure of 2 in your calaculations, and subsequently write on your certificate that the batteries do not have sufficient capacity to run the system, thereby giving everyone the impression that I don't know what I'm doing, I will sue the a**e off you!
In court, I will show the BS recommendation of calculation to the judge and leave it to you to argue with him why you think you know better than BS and have used another figure. Will the BFPSA back you up? I suggest that they will say that you misunderstood their advice.
Brain now totally failed and shutting down for urgent repairs- A drink at the Banter Bar might help. :)
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Of course that is all very well for Life systems, whats the calculations for a P system witha back up generator, UPS and windfarm ?
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One of the major issues behind the need to get batteries calculation in every service visit is, the temperature impact on the batteries life cycle, according to 'Arrhenius’ equation (Findings), For every 10 °C increase in temperature the reaction rate doubles. Therefore, an hour at 35 °C is roughly equivalent in battery life to two hours at 25 °C. In one side we can say the heat is the enemy of the battery and according to ‘Arrhenius’ even small increases in temperature will have a major influence on battery life cycle affecting both the desired and undesired chemical reactions.
The following figure explains this:
http://i472.photobucket.com/albums/rr87/BenzFerari/BattTemp.jpg
Benz - without trying to appear rude you have a tendancy to overcomplicate and go into too much detail on what are simple enough topics.
If the BS says use this calculation then I use it and if it is wrong for some reason then that's not my fault - I calculated to the formula given by BS5839!
Some of us are but mere fire alarm engineers!!
This reply doesn't coincide with the quote buzz!
Otherwise where is the complication and in relation to what post, we are discussing issues to learn better, and none is forcing none to uses what so ever :)
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The de-rating figure is to compensate for features of the battery and not of the system. However, the compensation for the battery is adjusted by features of the system. Your previous post explains the circumstances when you would use a de-rating figure of 1 or 1.75. These circumstances are not in the BS recommendation.
Wiz; No one said that circumstances are in the BS, however I quoted what you have stated in your previous posts, which are the following
Using a de-rating factor in your calculations provides a calaculation as taking into account of the fact that the battery's stated capacity in AH is a nominal figure because most batteries can't actaully meet their capacity rating on HIGH LOADS and are likely to exceed it on LOW LOADS. I.e a 24AH would probably be able to provide 1A for 30 hours but only 8 hours at 2.4A. The battery capacity is normally rated as if 1/20th is being taken out of it i.e if 1.2A was taken from a 24AH battery it would last 20 hours (i.e what you would expect from a 24AH battery!)
That's from where that circumstancies I stated come from :)
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Have you ever considered doing what BS recommends instead of what you think is right? It might save you grief in the future.
Wiz;
This forum is to discuss many issues in fire industry even issues coming from BS, or any other institutions, and the purpose is to understand better what is what, it is simple just to apply what is recommended by BS or BFPSA or any other recommender, but this will not prevent us to try to understand why things are done that way, it doesn't mean necessarely we know better than BS. since trying to understand is not against the standard in any way. also if some one prefered not to get involved to 'Why' and 'How' and just applies what is recommended, it still his own choice. and nothing wrong with that :)
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Of course that is all very well for Life systems, whats the calculations for a P system witha back up generator, UPS and windfarm ?
Don't you start as well!
-
One of the major issues behind the need to get batteries calculation in every service visit is, the temperature impact on the batteries life cycle, according to 'Arrhenius’ equation (Findings), For every 10 °C increase in temperature the reaction rate doubles. Therefore, an hour at 35 °C is roughly equivalent in battery life to two hours at 25 °C. In one side we can say the heat is the enemy of the battery and according to ‘Arrhenius’ even small increases in temperature will have a major influence on battery life cycle affecting both the desired and undesired chemical reactions.
The following figure explains this:
http://i472.photobucket.com/albums/rr87/BenzFerari/BattTemp.jpg
Benz - without trying to appear rude you have a tendancy to overcomplicate and go into too much detail on what are simple enough topics.
If the BS says use this calculation then I use it and if it is wrong for some reason then that's not my fault - I calculated to the formula given by BS5839!
Some of us are but mere fire alarm engineers!!
This reply doesn't coincide with the quote buzz!
Otherwise where is the complication and in relation to what post, we are discussing issues to learn better, and none is forcing none to uses what so ever :)
Sorry Benz but there would have been too many quotes to insert to back up my statement.
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Have you ever considered doing what BS recommends instead of what you think is right? It might save you grief in the future.
Wiz;
This forum is to discuss many issues in fire industry even issues coming from BS, or any other institutions, and the purpose is to understand better what is what, it is simple just to apply what is recommended by BS or BFPSA or any other recommender, but this will not prevent us to try to understand why things are done that way, it doesn't mean necessarely we know better than BS. since trying to understand is not against the standard in any way. also if some one prefered not to get involved to 'Why' and 'How' and just applies what is recommended, it still his own choice. and nothing wrong with that :)
The hope of resolving a lack of understanding is the reason why most of us post on Firnet.
Whilst I fully agree that it is great to discuss various things on a Forum such as this, we are mostly talking about life safety systems that are covered by design and installation recommendations which, if ignored, can involve serious legal issues.
There may be 10 ways to do something but only one of these may be included in the recommendations. In such cases, that one way is probably the right way.
For those that just 'dip' in and out of Firenet on an irregular basis seeking advice, we must make it totally clear which way is recommended by the standards and that anything else is just ideas, opinions and guessing. Most people don't want unrecommended options, they only want to know the 'right' way. The least we can do is to ensure they can recognise which is which.
I hope that this has been achieved.
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Thereby giving everyone the impression that I don't know what I'm doing, I will sue the a**e off you!
Wiz;
You really surprised me here, I have just realise that, I don't mean to be silly, we are just discussing things in a technical way, we may learn some thing new from each other, and that's the point.
If you technically convice me I will tel you thank you, as usually I do, if I convince you, you probably may have to say thank you ( if you want, but you are not obliged )...etc, and that's it. It's done.
Apart from the need to applying the recommendation of BS which every body knows that, this will not prevent us from discussing and sharing views..etc
have a nice day :)
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As Buz mentioned.
i have paid for,sat all FIA/BFPSA training schemes and i will continue to use their method i was taught and if it's wrong then i'm not to blame.
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Further readings in BFPSA books, Unit 5, Maintenance course, page 33, issue August 2006.
I found the following:
---------------------------------Start of BFPSA wording---------------------------------------------------------
Most batteries are designed to be fully discharged over a 20h period.
Design load = C / 20h.
De-rating Factor is:
The alarm load is usually much higher than the stand by load and this high current has to be allowed for in the battery calculation as the de-rating factor.
When the alarm load exceeds the design load then the battery could be considered of highly stressed and de-rating factor should be assumed to be D=2,
Example1:
The design load for a 2Ah battery would be 2Ah/20h = 0.1A
Example2:
The design load for 10Ah battery would be 10Ah/20h = 0.5A
For some systems the alarm load is quite low, perhaps nearly equal to the stand by load. In this case the battery is not stressed and factor D=1. This can make a small reduction to the calculation battery capacity.
-----------------------------------------------------End of BFPSA words-------------------------------------------
This is quite different to what wiz mentioned about BS version:
My question is:
1 - If the batteries are stressed means: (Alarm load > design load) and (D=2) what equation revealed that?
2 - If the batteries are not stressed means: (Alarm load = stand by load) and D=1 what equation revealed that?
I haven’t got a clue what’s going on in here
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although annex D of BS5839-1 2202 assumes a D factor of 1.75 the FIA/BFPSA recommends using a D factor of 2,which,whilst making very little difference to the final figure,will greatly simplifybattery calculation because a D of 2 multiplied by a T2(alarm time) of 0.5
will equal 1 and can therefore be ignored
furthermore by leaving the multiplication by 1.25(the ageing factor) until last will simplify the actual workings even more....
The quote above is word by word taken from BFPSA maintenance course, unit 5, page 33, issue: August 2006
All OK except: 2202 it should be 2002, and just to tel you Grame the brackets are there, they are a bit thin, hence no need to claim your money back :D
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I think you have to take into account what the BFPSA is in relation to the British Standards Institute and how relative each is in regards to recommendations or regulations.
My contracts state that a system is either designed,installed,commissioned or maintained to relevant BSI standards and to the recommendations within said standards.
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although annex D of BS5839-1 2202 assumes a D factor of 1.75 the FIA/BFPSA recommends using a D factor of 2,which,whilst making very little difference to the final figure,will greatly simplifybattery calculation because a D of 2 multiplied by a T2(alarm time) of 0.5
will equal 1 and can therefore be ignored
furthermore by leaving the multiplication by 1.25(the ageing factor) until last will simplify the actual workings even more....
The quote above is word by word taken from BFPSA maintenance course, unit 5, page 33, issue: August 2006
All OK except: 2202 it should be 2002, and just to tel you Grame the brackets are there, they are a bit thin, hence no need to claim your money back :D
thanks for pointing out that typo benz and just to let you know that i slept well last night for the first time in ages,as i was not worrying about de-rarting factors...
:D
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Further readings in BFPSA books, Unit 5, Maintenance course, page 33, issue August 2006.
I found the following:
---------------------------------Start of BFPSA wording---------------------------------------------------------
Most batteries are designed to be fully discharged over a 20h period.
Design load = C / 20h.
De-rating Factor is:
The alarm load is usually much higher than the stand by load and this high current has to be allowed for in the battery calculation as the de-rating factor.
When the alarm load exceeds the design load then the battery could be considered of highly stressed and de-rating factor should be assumed to be D=2,
Example1:
The design load for a 2Ah battery would be 2Ah/20h = 0.1A
Example2:
The design load for 10Ah battery would be 10Ah/20h = 0.5A
For some systems the alarm load is quite low, perhaps nearly equal to the stand by load. In this case the battery is not stressed and factor D=1. This can make a small reduction to the calculation battery capacity.
-----------------------------------------------------End of BFPSA words-------------------------------------------
This is quite different to what wiz mentioned about BS version:
My question is:
1 - If the batteries are stressed means: (Alarm load > design load) and (D=2) what equation revealed that?
2 - If the batteries are not stressed means: (Alarm load = stand by load) and D=1 what equation revealed that?
I haven’t got a clue what’s going on in here
Benz, I demand that you read my previous posts again and reconsider your latest comment:
This is quite different to what wiz mentioned about BS version:
You will find that much of what I have previously been explaining to you, you have now suddenly uncovered in your BFPSA book. Therefore it certainly is not quite different.
I would also point out that what I have been trying to get over to you is partly what BS recommends and partly my knowledge of the behaviour of batteries (which is not mentioned,as such, in BS). Both these elements are included in your latest BFPSA quote. Therefore I have previously mentioned every factor you now highlight in the BFPSA advice. You will also note that I have correctly highlighted the BFPSA advice that varies from the BS recommendations. I have even explained why they might use some different calculation figures, but explained that I do not agree that they should give this advice.
You do me a great dishonour by rubbishing my advice.
You seem to have an in-built system of misunderstanding, ignoring, disbelieving anything that I am telling you despite the fact that it is you that has asked for the advice in the first place. I appreciate that I may be poor at putting my points accross, although I have trained dozens of fire alarm engineers over the past 25 years with great success. Therefore I must assume that you either do not read my posts properly or are unable to understand them.
I'm sure you'll understand why I may well, in the future, choose not to join in on any of your posts.
Finally, I would, however make one final comment about the latest BFPSA advice you have quoted as follows:
When the alarm load exceeds the design load then the battery could be considered of highly stressed and de-rating factor should be assumed to be D=2,
Please note that the nearest equivalent advice in the BS recommendation quotes a figure of D=1.75 and finally, and most importantly, and as I explained at the very beginning, the BS recommendation is that any specific de-rating factor be obtained from that actual batterys' manufacturer, and in the absence of such, the figures of 1 or 1.75 should be used. BS never mentions the de-rating figure of 2.
In respect of your last two questions, the answers to both is that it is based on the behaviour of batteries to different discharge rates found through experience and testing by the manufacturer. There is probably a precise formula to calculate the behaviour and it will almost certainly include elements of chemical reaction. I do not know this formula. I suggest that you ask a battery manufacturer about it.
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As Buz mentioned.
i have paid for,sat all FIA/BFPSA training schemes and i will continue to use their method i was taught and if it's wrong then i'm not to blame.
Graeme, the method is not wrong as such. But it might give you a calcualtion that requires a higher battery capacity than the BS recommendation. Just don't use the BFPSA method calculation in an argument over whether a system's batteries have sufficient capacity or not, without re-checking using the BS figures. I'm sure that the BFPSA will admit their advice is based on the BS recommendations but that the BS takes precedence in any argument.
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As Buz mentioned.
i have paid for,sat all FIA/BFPSA training schemes and i will continue to use their method i was taught and if it's wrong then i'm not to blame.
Graeme, the method is not wrong as such. But it might give you a calcualtion that requires a higher battery capacity than the BS recommendation. Just don't use the BFPSA method calculation in an argument over whether a system's batteries have sufficient capacity or not, without re-checking using the BS figures. I'm sure that the BFPSA will admit their advice is based on the BS recommendations but that the BS takes precedence in any argument.
Like wot I said.
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As Buz mentioned.
i have paid for,sat all FIA/BFPSA training schemes and i will continue to use their method i was taught and if it's wrong then i'm not to blame.
Graeme, the method is not wrong as such. But it might give you a calcualtion that requires a higher battery capacity than the BS recommendation. Just don't use the BFPSA method calculation in an argument over whether a system's batteries have sufficient capacity or not, without re-checking using the BS figures. I'm sure that the BFPSA will admit their advice is based on the BS recommendations but that the BS takes precedence in any argument.
Like wot I said.
Yes. Spot on Buzz.
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As Buz mentioned.
i have paid for,sat all FIA/BFPSA training schemes and i will continue to use their method i was taught and if it's wrong then i'm not to blame.
Graeme, the method is not wrong as such. But it might give you a calcualtion that requires a higher battery capacity than the BS recommendation. Just don't use the BFPSA method calculation in an argument over whether a system's batteries have sufficient capacity or not, without re-checking using the BS figures. I'm sure that the BFPSA will admit their advice is based on the BS recommendations but that the BS takes precedence in any argument.
Wiz
that was not aimed at your goodself in case it was taken in such a way?
G
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Further readings in BFPSA books, Unit 5, Maintenance course, page 33, issue August 2006.
I found the following:
---------------------------------Start of BFPSA wording---------------------------------------------------------
Most batteries are designed to be fully discharged over a 20h period.
Design load = C / 20h.
De-rating Factor is:
The alarm load is usually much higher than the stand by load and this high current has to be allowed for in the battery calculation as the de-rating factor.
When the alarm load exceeds the design load then the battery could be considered of highly stressed and de-rating factor should be assumed to be D=2,
Example1:
The design load for a 2Ah battery would be 2Ah/20h = 0.1A
Example2:
The design load for 10Ah battery would be 10Ah/20h = 0.5A
For some systems the alarm load is quite low, perhaps nearly equal to the stand by load. In this case the battery is not stressed and factor D=1. This can make a small reduction to the calculation battery capacity.
-----------------------------------------------------End of BFPSA words-------------------------------------------
This is quite different to what wiz mentioned about BS version:
My question is:
1 - If the batteries are stressed means: (Alarm load > design load) and (D=2) what equation revealed that?
2 - If the batteries are not stressed means: (Alarm load = stand by load) and D=1 what equation revealed that?
I haven’t got a clue what’s going on in here
Benz, I demand that you read my previous posts again and reconsider your latest comment:
This is quite different to what wiz mentioned about BS version:
You will find that much of what I have previously been explaining to you, you have now suddenly uncovered in your BFPSA book. Therefore it certainly is not quite different.
I would also point out that what I have been trying to get over to you is partly what BS recommends and partly my knowledge of the behaviour of batteries (which is not mentioned,as such, in BS). Both these elements are included in your latest BFPSA quote. Therefore I have previously mentioned every factor you now highlight in the BFPSA advice. You will also note that I have correctly highlighted the BFPSA advice that varies from the BS recommendations. I have even explained why they might use some different calculation figures, but explained that I do not agree that they should give this advice.
You do me a great dishonour by rubbishing my advice.
You seem to have an in-built system of misunderstanding, ignoring, disbelieving anything that I am telling you despite the fact that it is you that has asked for the advice in the first place. I appreciate that I may be poor at putting my points accross, although I have trained dozens of fire alarm engineers over the past 25 years with great success. Therefore I must assume that you either do not read my posts properly or are unable to understand them.
I'm sure you'll understand why I may well, in the future, choose not to join in on any of your posts.
Finally, I would, however make one final comment about the latest BFPSA advice you have quoted as follows:
When the alarm load exceeds the design load then the battery could be considered of highly stressed and de-rating factor should be assumed to be D=2,
Please note that the nearest equivalent advice in the BS recommendation quotes a figure of D=1.75 and finally, and most importantly, and as I explained at the very beginning, the BS recommendation is that any specific de-rating factor be obtained from that actual batterys' manufacturer, and in the absence of such, the figures of 1 or 1.75 should be used. BS never mentions the de-rating figure of 2.
In respect of your last two questions, the answers to both is that it is based on the behaviour of batteries to different discharge rates found through experience and testing by the manufacturer. There is probably a precise formula to calculate the behaviour and it will almost certainly include elements of chemical reaction. I do not know this formula. I suggest that you ask a battery manufacturer about it.
i can ask if the guy on here selling axes,also has a gun?
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It is 1 when the system alarm load is equal or less than 1/20th of the battery's stated capacity. It is 1.75 when the battery's alarm load is greater than 1/20th of the battery's staed capacity.
If: Alarm load <= C/20 -------> D=1
But BFPSA said:
( For some systems the alarm load is quite low, perhaps nearly equal to the standby load. In this case the battery is not stressed and factor D=1. This can make a small reduction to the calculation battery capacity. )
If: Alarm load = Stand by load = I1 T1, and (Not = C/20) -----> D=1
The difference is: you are comparing the Alarm load with the 1/20th of full battery capacity = ‘C/20’, in order to set D=1. And BFPSA are comparing Alarm load with the standby load = I1 T1, In order to set D=1.
It is the same answer only when setting D=2 for BFPSA and D=1.75 for BS.
When alarm load > (design load = C/20)
This is what justifies what I said: (This is QUITE different to what wiz mentioned about) BS version:
Also you keep saying the same thing with a negation way:
You will find that much of what I have previously been explaining to you, you have now suddenly uncovered in your BFPSA book. Therefore it certainly is not QUITE different.
Finally I said (the cup is half empty) and you said (the cup is half full), sort of…etc
I am not rubbishing your advice Wiz, I am trying to decipher what you said, in a (No winner and No loser fashion), I just feel happy, only when I learn some thing new from any one…, or when some one say, your answer was useful and informative to me…etc, and that’s it
Have a nice day :)
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In the land of the blind the one-eyed man is king.
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In the land of the blind the one-eyed man is king.
Fortunately this is not a forum of the blind and hence there is no one-eyed man to be king.
-
In the land of the blind the one-eyed man is king.
Fortunately this is not a forum of the blind and hence there is no one-eyed man to be king.
Me thinks that that proverb has soared skyward without meaning!!!
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In the land of the blind the one-eyed man is king.
Fortunately this is not a forum of the blind and hence there is no one-eyed man to be king.
Me thinks that that proverb has soared skyward without meaning!!!
Along with much that went before!
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In the land of the blind the one-eyed man is king.
Fortunately this is not a forum of the blind and hence there is no one-eyed man to be king.
Me thinks that that proverb has soared skyward without meaning!!!
You mean the proverb not the answer to the proverb, if so you have quoted the wrong quote Buzz, as the answer to the proverb is not the proverb itself :)
This thread has been deviated enough from the original post, so it is this thread that has soared skyward without meaning
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Fortunately this is not a forum of the blind and hence there is no one-eyed man to be king.
Me thinks that that proverb has soared skyward without meaning!!!
You mean the proverb not the answer to the proverb, if so you have quoted the wrong quote Buzz, as the answer to the proverb is not the proverb itself :)
This thread has been deviated enough from the original post, so it is this thread that has soared skyward without meaning
....and hopefully never to land again!!!
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amen.
-
Very careful, if measuring EMS panel’s batteries! If the LSA batteries and the lithium battery are quite flat, you may loose the configuration (program) when disconnecting the mains to measure I2 (Alarm current), as the system will be warm started! Since batteries failure monitoring in EMS panel is not like other analogue addressable systems, EMS batteries failure can be cleared out either them selves or manually then it takes longer time to come back again… as it may not :)
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if the batteries are replaced every 4 years then there should be no danger of them dying when the 240v is removed.
EMS are a pain to do load tests as the battery leads are such a way that it is difficult to see what lead goes where.
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if the batteries are replaced every 4 years then there should be no danger of them dying when the 240v is removed.
.
It's not always the case Grame, that's why battery calculation has to be carried out every three months, four years may be the maximum period, as you may change them 2-3 times in four years, it's still depending on how many times there was cut of power and for for how long, also for how long alarm went off while the mains was cut off, also the factor of temperature which is found to be playing a major role in reducing the life cycle of the battery..., today I found a new heater fitted under the fire alarm system less then a meter far away, I found the panel really warm as well as the batteries, wich make the batteries draw current quicker than with lower temperature...
You may have realised why the battery tester gives you Voltage, current and temperature measurments all in one test!, the tester has been designed to take into account the temperature as well...etc
Also in three months time any thing could happen!
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Very careful, if measuring EMS panel’s batteries! If the LSA batteries and the lithium battery are quite flat, you may loose the configuration (program) when disconnecting the mains to measure I2 (Alarm current), as the system will be warm started! Since batteries failure monitoring in EMS panel is not like other analogue addressable systems, EMS batteries failure can be cleared out either them selves or manually then it takes longer time to come back again… as it may not :)
If you warm start an EMS panel you don't lose any information whatsoever.....
I think you may be talking about a cold start.
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Very careful, if measuring EMS panel’s batteries! If the LSA batteries and the lithium battery are quite flat, you may loose the configuration (program) when disconnecting the mains to measure I2 (Alarm current), as the system will be warm started! Since batteries failure monitoring in EMS panel is not like other analogue addressable systems, EMS batteries failure can be cleared out either them selves or manually then it takes longer time to come back again… as it may not :)
If you warm start an EMS panel you don't lose any information whatsoever.....
I think you may be talking about a cold start.
Thanks Dave, I am talking in here about 'cold start' (mains disconnected, with batteries flats including lithium battery...etc).
But, even warm start will lose information, it happened to me, it's either through selecting warm start on the program or just by pressing the back reset button (in the back of the lid) , give a try but make sure you have got back up...etc :)
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Benz we've installed about 200 EMS systems over the last 10 years.
We still service and maintain the vast majority.
If you lost information on a warm start I suggest you get onto EMS because you have a major problem..... :D
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Very careful, if measuring EMS panel’s batteries! If the LSA batteries and the lithium battery are quite flat, you may loose the configuration (program) when disconnecting the mains to measure I2 (Alarm current),
as the system will be warm started!
If you warm start an EMS panel you don't lose any information whatsoever.....
I think you may be talking about a cold start.
Thanks Dave, I am talking in here about 'cold start' (mains disconnected, with batteries flats including lithium battery...etc).
Sorry thought you were talking about warm starting......
??
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praise the Lord
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I think you may be talking about a cold start .
Sorry thought you were talking about warm starting......
I am no really sure who born first the chicken or the egg :)
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Benz we've installed about 200 EMS systems over the last 10 years.
We still service and maintain the vast majority.
If you lost information on a warm start I suggest you get onto EMS because you have a major problem..... :D
Yes indeed, we had lost information and it was sorted :)
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Thanks Dave, I am talking in here about 'cold start' (mains disconnected, with batteries flats including lithium battery...etc).
Sorry thought you were talking about warm starting......
??
I am no really sure who born first the chicken or the egg :)
I thought it was Adam.....?!
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I am no really sure who born first the chicken or the egg :)
I thought it was Adam.....?!
No Dinosaurs :)
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Spores!!!
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Microbes. Adam 'ad 'em!
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For a brand new system who has just been fitted and about to be commissioned, every body knows the batteries will take 24h to be fully charged once fitted...etc
Question 1: Would alarm current measurement should be taken after 24h?
Question 2: Would fire commissioning certificate be issued then, only after 24h, and not in the 1st day when
batteries are fitted?
Question 3: Would the current calculation taken the 1st day be considered not genuine?
Have your say!
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For a brand new system who has just been fitted and about to be commissioned, every body knows the batteries will take 24h to be fully charged once fitted...etc
Question 1: Would alarm current measurement should be taken after 24h?
Question 2: Would fire commissioning certificate be issued then, only after 24h, and not in the 1st day when
batteries are fitted?
Question 3: Would the current calculation taken the 1st day be considered not genuine?
Have your say!
1) Can be taken at any time.
However it is important to relate the current reading to the actual voltage of the battery at the time readings were taken. Using Ohms law can allow you to make adjustments. The system voltage is normally taken to be a nominal 24V dc. So If you take your alarm current readings on a battery supplying only 20V then by using Ohms law you can calculate what the alarm current would be at 24V. For example if we had a reading of 250mA at 20V it would be 300mA at 24V. If the battery voltage is reading greater than 24V we use the actual current readings taken and make no adjustment because the higher voltage reading errs on the right side for other calculations.
2) Issued on the basis of findings at the time of commissioning.
3) No.
A more important reason to leave a battery charging for at least 20 hours before taking any readings is to establish it is not being overcharged by being charged at a high rate even though 'fully charged'. This would happen if the battery charging circuit is faulty or wrongly calibrated. Continuing to charge a SLA battery at a high rate after it has reached full charge will damage it.
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For a brand new system who has just been fitted and about to be commissioned, every body knows the batteries will take 24h to be fully charged once fitted...etc
Question 1: Would alarm current measurement should be taken after 24h?
Question 2: Would fire commissioning certificate be issued then, only after 24h, and not in the 1st day when
batteries are fitted?
Question 3: Would the current calculation taken the 1st day be considered not genuine?
Have your say!
1) Can be taken at any time.
However it is important to relate the current reading to the actual voltage of the battery at the time readings were taken. Using Ohms law can allow you to make adjustments. The system voltage is normally taken to be a nominal 24V dc. So If you take your alarm current readings on a battery supplying only 20V then by using Ohms law you can calculate what the alarm current would be at 24V. For example if we had a reading of 250mA at 20V it would be 300mA at 24V. If the battery voltage is reading greater than 24V we use the actual current readings taken and make no adjustment because the higher voltage reading errs on the right side for other calculations.
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This make sense, and this is your best answer ever Wiz. even I didn't totaly agree with all your answers :)
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For a brand new system who has just been fitted and about to be commissioned, every body knows the batteries will take 24h to be fully charged once fitted...etc
Question 1: Would alarm current measurement should be taken after 24h?
Question 2: Would fire commissioning certificate be issued then, only after 24h, and not in the 1st day when
batteries are fitted?
Question 3: Would the current calculation taken the 1st day be considered not genuine?
Have your say!
2) Issued on the basis of findings at the time of commissioning.
.
In here, I may disagree, till you convince me, if the batteries has just been fitted, and both voltage and current haven't yet reached their top value (Full charge), therefore the calculation will be done while taking into account the necessary adjustement through Ohm's Law...etc
Imagine you have finished your commissioning in couple of hours of batteries fitting, if you issue the certificate of commissioning straight forward, what's the guaranty the batteries will supply half hour supply in case of mains failure, as the batteries are not yet fully charged? :)
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For a brand new system who has just been fitted and about to be commissioned, every body knows the batteries will take 24h to be fully charged once fitted...etc
Question 1: Would alarm current measurement should be taken after 24h?
Question 2: Would fire commissioning certificate be issued then, only after 24h, and not in the 1st day when
batteries are fitted?
Question 3: Would the current calculation taken the 1st day be considered not genuine?
Have your say!
3) No.
A more important reason to leave a battery charging for at least 20 hours before taking any readings is to establish it is not being overcharged by being charged at a high rate even though 'fully charged'. This would happen if the battery charging circuit is faulty or wrongly calibrated. Continuing to charge a SLA battery at a high rate after it has reached full charge will damage it.
This is very important point, but what about, the guaranty of half hour alarm supply and 48h of stand by in case of mains cut, since the batteries are not yet fully charged?
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For a brand new system who has just been fitted and about to be commissioned, every body knows the batteries will take 24h to be fully charged once fitted...etc
Question 1: Would alarm current measurement should be taken after 24h?
Question 2: Would fire commissioning certificate be issued then, only after 24h, and not in the 1st day when
batteries are fitted?
Question 3: Would the current calculation taken the 1st day be considered not genuine?
Have your say!
2) Issued on the basis of findings at the time of commissioning.
.
In here, I may disagree, till you convince me, if the batteries has just been fitted, and both voltage and current haven't yet reached their top value (Full charge), therefore the calculation will be done while taking into account the necessary adjustement through Ohm's Law...etc
Imagine you have finished your commissioning in couple of hours of batteries fitting, if you issue the certificate of commissioning straight forward, what's the guaranty the batteries will supply half hour supply in case of mains failure, as the batteries are not yet fully charged? :)
I'm basing my answers on what the BS recommends, not what some may consider to be better practice. BS doesn't recommend you to carry out a commissioning only when the batteries are fully charged. You or I might feel that it would be good practice not to put a system 'in service' until the battery is fully charged but who are we to try to convince anyone our ideas are more important than BS recommendations?
Finally, I also don't necessarily agree that issuing a BS commissioning certificate at any time is giving any guarantee that the battery has the required capacity available at just that moment in time.
Surely the certificate is stating that when readings were taken and calculations were made, a fully charged battery would provide the standby duty required of BS recommendations. Therefore it doesn't matter if you issue the certificate 'there and then', a day later or two weeks later. The certificate is surely based on the proviso that the battery is in a suitably charged state!
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For a brand new system who has just been fitted and about to be commissioned, every body knows the batteries will take 24h to be fully charged once fitted...etc
Question 1: Would alarm current measurement should be taken after 24h?
Question 2: Would fire commissioning certificate be issued then, only after 24h, and not in the 1st day when
batteries are fitted?
Question 3: Would the current calculation taken the 1st day be considered not genuine?
Have your say!
3) No.
A more important reason to leave a battery charging for at least 20 hours before taking any readings is to establish it is not being overcharged by being charged at a high rate even though 'fully charged'. This would happen if the battery charging circuit is faulty or wrongly calibrated. Continuing to charge a SLA battery at a high rate after it has reached full charge will damage it.
This is very important point, but what about, the guaranty of half hour alarm supply and 48h of stand by in case of mains cut, since the batteries are not yet fully charged?
I don't know where you get the 48H figure from unless you are talking about a specific Cat. P system.
In all events your question 3 asked Would the current calculation taken the 1st day be considered not genuine? and the 'current' you were talking about is the 'alarm current', so this should stay the same (taking into account the voltage at the time of measurement, as explained previously) and it can't change by itself (i.e. the components of the system that draw the alarm current won't change depending on the state of the charge of the battery) over any period of time. So, in answer, to your question Would the current calculation taken the 1st day be considered not genuine? the answer is no, it won't be considered 'not genuine'.
I love double-negatives!
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For a brand new system who has just been fitted and about to be commissioned, every body knows the batteries will take 24h to be fully charged once fitted...etc
Question 1: Would alarm current measurement should be taken after 24h?
Question 2: Would fire commissioning certificate be issued then, only after 24h, and not in the 1st day when
batteries are fitted?
Question 3: Would the current calculation taken the 1st day be considered not genuine?
Have your say!
2) Issued on the basis of findings at the time of commissioning.
.
In here, I may disagree, till you convince me, if the batteries has just been fitted, and both voltage and current haven't yet reached their top value (Full charge), therefore the calculation will be done while taking into account the necessary adjustement through Ohm's Law...etc
Imagine you have finished your commissioning in couple of hours of batteries fitting, if you issue the certificate of commissioning straight forward, what's the guaranty the batteries will supply half hour supply in case of mains failure, as the batteries are not yet fully charged? :)
You have to be realistic here Benz in balancing the theoritical optimum battery maximum level versus the commercial time of installation/power up/commissioning.
Formula and theory do not a real world make!
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2) Issued on the basis of findings at the time of commissioning.
.
In here, I may disagree, till you convince me, if the batteries has just been fitted, and both voltage and current haven't yet reached their top value (Full charge), therefore the calculation will be done while taking into account the necessary adjustement through Ohm's Law...etc
Imagine you have finished your commissioning in couple of hours of batteries fitting, if you issue the certificate of commissioning straight forward, what's the guaranty the batteries will supply half hour supply in case of mains failure, as the batteries are not yet fully charged? :)
I'm basing my answers on what the BS recommends, not what some may consider to be better practice. BS doesn't recommend you to carry out a commissioning only when the batteries are fully charged. You or I might feel that it would be good practice not to put a system 'in service' until the battery is fully charged but who are we to try to convince anyone our ideas are more important than BS recommendations?
We are not at all, in a position to compare our sayings and ideas to BS recommendations (PLEASE FORGET THAT), BS has its says and you usually mentioned what BS suggests as recommendations...and that’s fairly good (affair classified)...but it has never meant to be end of thinking and supplying opinions..., our views remain just as technical views..., etc
Also all what BS have stated and sets as recommendations, it still human findings through long research and testing and analyzing...and I do appreciate that, and BS itself is under overview from time to time, and it will never ever be 100% complete and perfect... etc. we live in variably changing world, and what is relatively perfect today might not by next couple of years, and that’s what make humans thinking and analyzing things for better refinements and findings...etc
Also it’s very good if you can supply both what BS recommends and what you personally think, in a friendly manner, but it will never mean that you know better than BS :)
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I love double-negatives!
Indeed, to come back to affirmatives, instead of simply reversing… assuming it’s just another way, but don’t tel you car hasn't got reverse gear, you like one way system and there is nothing wrong with that, but it may cost more fuel some times, which means more unnecessary spent of money, even in digital electronics, it's still negation of negation = affirmation, but not advisable to be used all the time, it may consume memory space…, long processing…, a lot of logic gates…., etc :)
You agree we are just joking and learning at the same time :)
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2) Issued on the basis of findings at the time of commissioning.
.
In here, I may disagree, till you convince me, if the batteries has just been fitted, and both voltage and current haven't yet reached their top value (Full charge), therefore the calculation will be done while taking into account the necessary adjustement through Ohm's Law...etc
Imagine you have finished your commissioning in couple of hours of batteries fitting, if you issue the certificate of commissioning straight forward, what's the guaranty the batteries will supply half hour supply in case of mains failure, as the batteries are not yet fully charged? :)
You have to be realistic here Benz in balancing the theoritical optimum battery maximum level versus the commercial time of installation/power up/commissioning.
Formula and theory do not a real world make!
It's realism that lets me rise up this concern :)
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After doing many batteries capacity calculations in many sites, I have realized that the new calculated capacity is even lower than the smallest batteries capa. reading when using the normal battery tester... i.e.
Today I had:
When using the Ampermeter in serial with the batt:
I1 = 9mA
I2 = 22mA C = 0.549 Ah (If T1 = 48h) and C = 0.29 Ah (If T1=24h)
When measuring with the normal Batt. Tester, I got:
Batt 1: 1.79Ah
Batt 2: 0.94Ah
Any technical interpretations ?
Thank you
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Document No.996-131 Issue 02, Installation Manual of Morley IAS, stated in page 40: the following:
New Batteries require 'top charging' prior to being put into service.
Yuassa recommends top charging at 28.8Vdc for 15 to 20hours for batteries up to 6 months old from date of manufacture.
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The same document: No.996-131 Issue 02, Installation Manual of Morley IAS, stated in page 38 some adjustment factors:
1 - For Apollo and Hochiki devices: multiply by 1.5
2 - For System Sensor and Nittan devices: multiply by 1.25
It seems manufacturer guides too, have to be considered, not just BS recommendations!
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I don't know where you get the 48H figure from unless you are talking about a specific Cat. P system.
In all events your question 3 asked Would the current calculation taken the 1st day be considered not genuine? and the 'current' you were talking about is the 'alarm current', so this should stay the same (taking into account the voltage at the time of measurement, as explained previously) and it can't change by itself (i.e. the components of the system that draw the alarm current won't change depending on the state of the charge of the battery) over any period of time. So, in answer, to your question Would the current calculation taken the 1st day be considered not genuine? the answer is no, it won't be considered 'not genuine'.
I love double-negatives!
1 - T1 = 24h till 72h it depends of.., but is not the main issue.
2 - I was talking about both stand by current and alarm current.
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After doing many batteries capacity calculations in many sites, I have realized that the new calculated capacity is even lower than the smallest batteries capa. reading when using the normal battery tester... i.e.
Today I had:
When using the Ampermeter in serial with the batt:
I1 = 9mA
I2 = 22mA C = 0.549 Ah (If T1 = 48h) and C = 0.29 Ah (If T1=24h)
When measuring with the normal Batt. Tester, I got:
Batt 1: 1.79Ah
Batt 2: 0.94Ah
Any technical interpretations ?
Thank you
After nice double espresso and good sleep I realized that, the batteries tester gives a higher reading than when calculating the batteries capacity while taking into account I1 and I2 readings...., this is evident since the batteries tester takes measurements OFF load, while the batteries calculation through I1 and I2 readings..., are done with the load.
My though is; the battery calculation is more genuine than testing batteries capacity with batteries tester.
Time is due for another double espresso :)
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Benz, you've started talking to yourself here :)
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Benz, you've started talking to yourself here :)
...."TAXI for Benzerari"!!!!!
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Benz, you've started talking to yourself here :)
I used to :)
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Benz, you've started talking to yourself here :)
...."TAXI for Benzerari"!!!!!
Ambulance instead! I worked last week in Psyciatric Hospital (the whole week), I think that's why :D
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Benz, you've started talking to yourself here :)
...."TAXI for Benzerari"!!!!!
Ambulance instead! I worked last week in Psyciatric Hospital (the whole week), I think that's why :D
...and they let you leave?????
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...."TAXI for Benzerari"!!!!!
Ambulance instead! I worked last week in Psyciatric Hospital (the whole week), I think that's why :D
...and they let you leave?????
Probably they didn't realize, that's why, If they did, they wouldn't let me out, or may be, there isn't enough room any more... :D
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Today, I have confirmed the 'Warm Start' in EMS panel didn't lose the configuration (info) so Dave was right, but the previous one I dealt with It did, what was going on with the previous one then?
I don't know? Even EMS Technical Support today were very busy, I couldn't get in hold of them :)
I was obliged to use today the 'Warm Start' to clear out (BT fault: battery fault) even I had replaced them with brand new ones :)
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Benz
you are not supposed to use the warm start to clear faults..
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Benz
you are not supposed to use the warm start to clear faults..
What's your suggestions then, to clear it out?
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isolate/re-enable device
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isolate/re-enable device
Ohhh, Grame; you are talking about the door, while I am talking about the window...
I said battery fault and not device fault, I am talking about the panels batteries (2*12Vdc, 7Ah), I replaced them by brand new ones, the fault didn't clear out, even through system reset option...
That's what let me thinking about 'Warm Start', as the fault isn't any more genuine fault, it just couldn't cleared out form the display... etc
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it should have cleared after pressing mute sounders a few times then reset a few times with keyswitch on.
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it should have cleared after pressing mute sounders a few times then reset a few times with keyswitch on.
Sorry, but it didn't mate :)
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Another useful way to clear odd faults is to change the clock to 11.59 pm and let it change to midnight .... the panel does a bit of a self test and collects all the battery info from the radio devices....
So i take it this is a Mark 1 panel then....?
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For the case we are talking about of (BT fault), I found through event history that a repetition of a series of the same messages:
Battery charging OK, date... time...
Battery test fail, date..., time...
Battery charging OK, date... time...
Battery test fail, date..., time...
Battery charging OK, date... time...
Battery test fail, date..., time...
Battery charging OK, date... time...
Battery test fail, date..., time...
But this has no thing to do with device's batteries...! rather it was panels fault: BT...
Obviously, when tried to test the panel batteries with a battery tester, the battery tester didn't come on at all..., blank display..., batteries totaly dead, and once replaced them by brand new ones, and pressed silence and reset, nothing happened, tried the system reset option several times, nothing happened..., the (BT fault) didn't clear from the display, I guessed that due to the processor reported the (battery faulty) for so many times, it classified it as permanent fault, and stopped testing the batteries..., threfore it needs then a proper reset which is called (warm start with EMS 5000 panel), otherwise I have to wait for I don't know how long, to get it cleared out from the display... etc
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Another useful way to clear odd faults is to change the clock to 11.59 pm and let it change to midnight .... the panel does a bit of a self test and collects all the battery info from the radio devices....
So i take it this is a Mark 1 panel then....?
Good deal Dave, that means you speed up the processing..., very good idea (http://i472.photobucket.com/albums/rr87/BenzFerari/icon_thumright1.gif)
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About the timer issue, my interpretation (but; I might be wrong) is that, once the device is logged on, and start to be operational, its timer trigger to start counting down, the idea is i.e. its battery will take five years to run out (Obviously in theory) or say in (Ideal conditions...) i.e. after one year you will get 80% left, but there are very less probability this theory value may coincide with the practical (actual) battery value, hence the best way to find out, is to trace what the processor reported to event history when the processor tests either device's batteries or panel batteries… :)
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Benz... I'm not totally sure but my best guess (relating to the mk3 alkaline devices) is this....
I think the devices are pre-programmed to send out there battery status maybe every 24 hours. There is no timer involved in the panel whatsoever.... the panel does not display any battery information or percentage of battery left until the panel sees a low battery signal from a device.
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Benz... I'm not totally sure but my best guess (relating to the mk3 alkaline devices) is this....
I think the devices are pre-programmed to send out there battery status maybe every 24 hours. There is no timer involved in the panel whatsoever.... the panel does not display any battery information or percentage of battery left until the panel sees a low battery signal from a device.
It's EMS who said there is timer for batteries the one giving the left batteries percentage through 'device data base'..., and as usual they drop very thin droplette of info each time I call them to seeking advise, they don't want to give more details, my last interpretation in the previous post was based on the role of the microprocessor in general combined with, what I received from EMS...etc
I hope one day I can get in touch with them, to discuss things in details... but I am pretty sure they don't want like any manufacturer, to give further secrets of how the system is designed to operate... etc
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Benz... I'm not totally sure but my best guess (relating to the mk3 alkaline devices) is this....
I think the devices are pre-programmed to send out there battery status maybe every 24 hours. There is no timer involved in the panel whatsoever.... the panel does not display any battery information or percentage of battery left until the panel sees a low battery signal from a device.
Just to mention the timer of each device, must be embeded in the devices itself and not in the panel, the one in the panel may be for the panel batteries... etc we are just guessing according to the available knowledge... etc
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No the panel batteries are monitored in the usual manner.
There is a difference between lithium (mk 1) powered devices - you will get a % left in the device database as you say.... but alkaline powered devices (mk 3) don't deliver any battery info to the panel so you will never see a % left.
You will only get a low battery warning from a mk 3 device (or batt A/B/C etc)
As said the "timer" is embedded in the lithium battery boards.... the "% left" is the panels interpretation of the battery info received each 24 hours. Hence EMS issued a firware upgrade about 6-7 years ago when we found the battery life (according to the panel) was nearly zero after around three years... after the upgrade the battery life was up by around 40%.....????!!!
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No the panel batteries are monitored in the usual manner.
There is a difference between lithium (mk 1) powered devices - you will get a % left in the device database as you say.... but alkaline powered devices (mk 3) don't deliver any battery info to the panel so you will never see a % left.
You will only get a low battery warning from a mk 3 device (or batt A/B/C etc)
As said the "timer" is embedded in the lithium battery boards.... the "% left" is the panels interpretation of the battery info received each 24 hours. Hence EMS issued a firware upgrade about 6-7 years ago when we found the battery life (according to the panel) was nearly zero after around three years... after the upgrade the battery life was up by around 40%.....????!!!
From where did you get that, don't tell you paid them special dinner to get this info, but if you have any secret's guides then please supply us :)
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. Hence EMS issued a firware upgrade about 6-7 years ago when we found the battery life (according to the panel) was nearly zero after around three years... after the upgrade the battery life was up by around 40%.....????!!!
Means now they are supposed to run for five years then, isn't? :)
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No the panel batteries are monitored in the usual manner.
There is a difference between lithium (mk 1) powered devices - you will get a % left in the device database as you say.... but alkaline powered devices (mk 3) don't deliver any battery info to the panel so you will never see a % left.
You will only get a low battery warning from a mk 3 device (or batt A/B/C etc)
As said the "timer" is embedded in the lithium battery boards.... the "% left" is the panels interpretation of the battery info received each 24 hours. Hence EMS issued a firware upgrade about 6-7 years ago when we found the battery life (according to the panel) was nearly zero after around three years... after the upgrade the battery life was up by around 40%.....????!!!
From where did you get that, don't tell you paid them special dinner to get this info, but if you have any secret's guides then please supply us :)
Most of the info is gained from working with the systems on a daily basis for about the last 10 years....and through taking their technical bods out the back and giving them a good kickin till they talked....!!
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. Hence EMS issued a firware upgrade about 6-7 years ago when we found the battery life (according to the panel) was nearly zero after around three years... after the upgrade the battery life was up by around 40%.....????!!!
Means now they are supposed to run for five years then, isn't? :)
Allegedly so....
In all honesty they used to... but they had all sorts of battery problems a few years ago when the manufacture changed from England to France and the quality of the batteries dropped off the scale.
We tell everyone to expect 4 years maximum.... unless they're using voice sounders and they are only 2.5 years....!!!
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. Hence EMS issued a firware upgrade about 6-7 years ago when we found the battery life (according to the panel) was nearly zero after around three years... after the upgrade the battery life was up by around 40%.....????!!!
Means now they are supposed to run for five years then, isn't? :)
Allegedly so....
In all honesty they used to... but they had all sorts of battery problems a few years ago when the manufacture changed from England to France and the quality of the batteries dropped off the scale.
We tell everyone to expect 4 years maximum.... unless they're using voice sounders and they are only 2.5 years....!!!
Are you blaming France of its bad batteries quality ?
It was a French scientist, who first invented VRLA (Valve Regulated Sealed Lead Acid) batteries a while ago! :D
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Are you blaming France of its bad batteries quality ?
It was a French scientist, who first invented VRLA (Valve Regulated Sealed Lead Acid) batteries a while ago! :D
And I dont think Georges Leclanche was a Englishman.
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Means now they are supposed to run for five years then, isn't? :)
Allegedly so....
In all honesty they used to... but they had all sorts of battery problems a few years ago when the manufacture changed from England to France and the quality of the batteries dropped off the scale.
We tell everyone to expect 4 years maximum.... unless they're using voice sounders and they are only 2.5 years....!!!
Are you blaming France of its bad batteries quality ?
It was a French scientist, who first invented VRLA (Valve Regulated Sealed Lead Acid) batteries a while ago! :D
VRLA had first been invented in 1859 by ‘Gaston Planté’ and first demonstrated to the French Academy of Sciences in 1860... etc
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Are you blaming France of its bad batteries quality ?
It was a French scientist, who first invented VRLA (Valve Regulated Sealed Lead Acid) batteries a while ago! :D
And I dont think Georges Leclanche was a Englishman.
Indeed Kurnal :)
George Leclanché was born in Parmain (France) in 1839. He was the son of Léopold Leclanché and Eugenie of Villeneuve. Leclanché was educated in England. He returned to France to continue his study in the Central School of Arts and Manufactures. After completing a technical education in 1860, Leclanché began work as an engineer. Six years later he developed his battery, which contained a conducting solution (electrolyte) of ammonium chloride, a negative terminal of zinc, and a positive terminal of manganese di. In 1866, Georges Leclanche patented a new system, which was immediately successful.
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Are you blaming France of its bad batteries quality ?
It was a French scientist, who first invented VRLA (Valve Regulated Sealed Lead Acid) batteries a while ago! :D
And I dont think Georges Leclanche was a Englishman.
Indeed Kurnal :)
George Leclanché was born in Parmain (France) in 1839. He was the son of Léopold Leclanché and Eugenie of Villeneuve. Leclanché was educated in England. He returned to France to continue his study in the Central School of Arts and Manufactures. After completing a technical education in 1860, Leclanché began work as an engineer. Six years later he developed his battery, which contained a conducting solution (electrolyte) of ammonium chloride, a negative terminal of zinc, and a positive terminal of manganese di. In 1866, Georges Leclanche patented a new system, which was immediately successful.
...ain't wiki a wonderful thing?!
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And I dont think Georges Leclanche was a Englishman.
Indeed Kurnal :)
George Leclanché was born in Parmain (France) in 1839. He was the son of Léopold Leclanché and Eugenie of Villeneuve. Leclanché was educated in England. He returned to France to continue his study in the Central School of Arts and Manufactures. After completing a technical education in 1860, Leclanché began work as an engineer. Six years later he developed his battery, which contained a conducting solution (electrolyte) of ammonium chloride, a negative terminal of zinc, and a positive terminal of manganese di. In 1866, Georges Leclanche patented a new system, which was immediately successful.
...ain't wiki a wonderful thing?!
'pedia' is the missing link, isn't it? :D
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You lot have to much time on your hands, Has anyone got a programme that will do the calculations.
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You lot have to much time on your hands, Has anyone got a programme that will do the calculations.
The dispute and discussions went on, to explain the right method rather than how to use batt. calculation program, once the method is clear enough, it wouldn't be a big issue to program it, then use its program :)
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..........It was a French scientist, who first invented VRLA (Valve Regulated Sealed Lead Acid) batteries a while ago! :D
Benz, surely you are talking about the lead acid bit. I think you'll find the valve regulation came much much later.
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You lot have to much time on your hands, Has anyone got a programme that will do the calculations.
Thomas, are you looking for a programme to calculate the capacity of batteries required in a system (i.e. design) or for a programme to calculate the likely standby duty of the existing batteries insatalled in an existing system (maintenance)?
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You lot have to much time on your hands, Has anyone got a programme that will do the calculations.
Thomas, are you looking for a programme to calculate the capacity of batteries required in a system (i.e. design) or for a programme to calculate the likely standby duty of the existing batteries insatalled in an existing system (maintenance)?
If youve got them both would be great.
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..........It was a French scientist, who first invented VRLA (Valve Regulated Sealed Lead Acid) batteries a while ago! :D
Benz, surely you are talking about the lead acid bit. I think you'll find the valve regulation came much much later.
When, where and by who? it needs proper referencing in this issue! :)
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I Have recently found in one site, the batteries box fitted far away from the fire alarm panel, say 25-30m, the question is:
1- Would that distance affect the batteries capacity calculation?
2- Would that distance cause volt drop?
I also found in some other different sites, the batteries box fitted in the basement while the main panel fitted in ground floor entrance, the distance is about 60m
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I Have recently found in one site, the batteries box fitted far away from the fire alarm panel, say 25-30m, the question is:
1- Would that distance affect the batteries capacity calculation?
2- Would that distance cause volt drop?
I also found in some other different sites, the batteries box fitted in the basement while the main panel fitted in ground floor entrance, the distance is about 60m
This has no apreciable effect on the battery capacity calculation.
There are obviously some volt drop issues. However fire alarms take relatively small currents and 60m of, say, 1.5mm cable would add very little volt drop even on full load. Obviously all volt drop on full load needs to be taken into consideration but it is likely to be a small problem in most cases.
The big problem with remotely sited batteries is the volt-drop affecting the charge circuit monitoring. This is not a problem on remotely sited batteries that also contain the charging circuit. The voltage of a battery is critical in the decision of how an automatic charging circuit will decide on how to continue charging it.
For example,a nominal 24v fire alarm system, will charge it's SLA batteries to obtain a full charge indicated as something in the the region of 27.5V. i.e below this voltage the charger will continue to try and charge them to reach that voltage and when it reaches it, the charging current rate will reduce to give them a trickle charge.
If you try to charge above trickle charge rate when the battery reaches it's fully-charged state (as indicated by a voltage of approx. 27.5V) then this will damage the batteries by overcharging them.
Therefore if your batteries are sited 60m away from the charging circuit, when the charging circuit monitors the battery voltage (to determine their charge state) it may get a reading of, say, 26.5V and decide it needs to continue charging the batteries at a higher than trickle charge rate. However if your 60m of cable is actaully causing a 1V volt drop due to the length of the connecting cable, then the batteries are actually at 27.5V (and fully charged). The false battery voltage reading due to the volt drop will cause the charger to carry on charging at a higher than necessary rate and damage the batteries.
In my experience, even a distance of a few metres between charging circuit and battery creates enough volt drop to affect the charging circuit and a 2.5mm or 4mm battery connection is required. You might find that 60m of cable requires a very hefty sized cable to get around the problem!
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You lot have to much time on your hands, Has anyone got a programme that will do the calculations.
Thomas, are you looking for a programme to calculate the capacity of batteries required in a system (i.e. design) or for a programme to calculate the likely standby duty of the existing batteries insatalled in an existing system (maintenance)?
If youve got them both would be great.
Thomas
don't know waht you use but i use Advanced and Apollo. Use the Apollo loop cal to get your I1 and I2 per loop and then transfer onto the Advanced panle calculator to get your min batteries required. I will e-mail you if needed.
Graeme.,
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Would be good, if you can email it, tom@lindumfire.co.uk
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done. you have mail
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Thanks Greame,
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Gent Vigilon has two separate sets of standby batteries, each supplies around 24Vdc, thus 2 batt. inputs to the system. The question is;
In order to satisfy BAFE batteries calculation, is it a must to make batteries calculation for each set of batteries and thus each set has to supply above 70% capacity..., or their sum should supply above 70% capacity?
What do you think?
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Also for radio system, the batteries in charge of supplying power to an alarm output is the batteries fitted in the each sounder device and not the main standby battery at the panel, obviously if the hard wired outpout radial circuit is not used, the question is;
- Is it a must to check batteries in every single sounder device and see if it still above 70% of its capacity?
- What about the batteries calculation, is it really required in this issue?
What do you think
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Gent Vigilon has two separate sets of standby batteries, each supplies around 24Vdc, thus 2 batteries inputs to the system. The question is;
In order to satisfy BAFE batteries calculation, is it a must to make batteries calculation for each set of batteries and thus each set has to supply above 70% capacity, or their sum should supply above 70% capacity?
What do you think?
Need some clear answer to the above Guys! also why Gent haven't combined its sets of batteries into one single set to clear out this ambiguity?
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Benz,
I think you'll find that the current Gent Vigilon only has one set of batteries...
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Benz,
I think you'll find that the current Gent Vigilon only has one set of batteries...
So what are the inputs of B1 and B2 into the back PCB board, on the top right hand corner then? aren't they come of two separate sets of batteries?
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Benz,
I think you'll find that the current Gent Vigilon only has one set of batteries...
So what are the inputs of B1 and B2 into the back PCB board, on the top right hand corner then? aren't they come of two separate sets of batteries?
So long since I looked in one but doesn't each battery have it's set of terminals?
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Benz,
I think you'll find that the current Gent Vigilon only has one set of batteries...
So what are the inputs of B1 and B2 into the back PCB board, on the top right hand corner then? aren't they come of two separate sets of batteries?
So long since I looked in one but doesn't each battery have it's set of terminals?
Indeed is not each battery has its set of terminals, it's rather 2 batteries as one set supplying 24Vdc to terminal B1 in the PCB board, and 2 other batteries as one set supplying 24Vdc to terminal B2, thus two inputs from two different sets of batteries.
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Benz,
When I said the current vigilon, I meant the 6 loop. This has a different PSU to the older Vigilon and utilises only one set of batteries which are now housed in the panel instead of a seperate battery box....
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Benz,
When I said the current vigilon, I meant the 6 loop. This has a different PSU to the older Vigilon and utilises only one set of batteries which are now housed in the panel instead of a seperate battery box....
Still the issue with BAFE requirement in regards to the so called old Vigilon 4loops and 2loops, how the 70% capacity requirement is defined, per set of batteries or their sum?