Automatic Detector Removal

[Wiz]

another little one,smoke detectors often go off when they detect steam.

I take it that my musings are too in-depth for this forum!!!!!  Where are you when I need you Kurnal?

[kurnal]

Wiz
How kind you are to imply faith in my jabberings. I have been holding back on this one for two reasons- the first is that I dont know the answer and secondly hoping that someone else would know and then I could agree with them, pretend I had been very busy and look very clever indeed.
I thought the hirsute man of Northern  England may had had a stab at it as well.

I dont have any knowlege of the change to BS that you refer to.

But  heres a stab at a possible explanation. As alarm systems have developed over the years I guess that, as GM infers above, the operation of MCPs would be seen as sacrosanct.  After all if someone operates one of those then you do have a fire for real and it matters big time. Whereas at first the use of detection  was seen as potentially unreliable at first and was a bonus used in conjunction with the traditional passive methods of fire safety.

I also remember an early system in a hospital that used to be prone to unwanted signals (thrips and the like) and after the second call of the evening we firefighters  had a policy (in our ignorance) of just unplugging the detector head involved. So thats all right then! Yes I shudder to think of the consequences now.


But now things have changed and AFD is now used in the basic fire strategy for a building and often in lieu of other methods of fire protection. So it becomes absolutely vital that if it is part of a fire strategy must be bulletproof.  And as it happens the technology has advanced at the same time to ensure that  first by by the use of diodes, then active EOLs and now intelligent systems the  resilience of the system has also improved in parallel. Almost by co-incidence.

But you are right- It does seem surprising that the BS does not appear to have kept pace.

Sorry not to be of any more use on this one. But I don't pretend to be a techie. And your question has at least prompted me to read around the subject again. Have to go now- I can hear the nurse coming.

[Wiz]

Kurnal, thanks for input. It seems my belief that the inclusion of afd in the recommendation as an earlier ammendment and dropped for 2002 was another figment of my delerious imagination. Graeme almost certainly hit the nail on the head about why mcps are considered more important and I agree with you that it makes no sense that the latest standard couldn't incoporate something that seems so obvious.

Lucky had me going for a while. But I'm now guessing that he strayed into the wrong place by mistake and had to say something to cover his embaressment before leaving. I think he might even be a fellow resident in this Home For The Bewildered. I'm now keeping my eye on a couple fellow residents because they always seem to be a bit 'lucky' with portion size when the tiramasu is dealt out at lunchtime!

Later Edit;
Now I'm sure about my suspicions of Lucky! I've just read his previous posts elsewhere in this forum and one contains the words 'staff are making it difficult to carry out the roll' . I tried to get out yesterday with a bit of steak and onion pie in my pocket and Matron was very angry. And I would imagine that the roll must have been very big if he had to carry it! He should have asked for my help!

[Thebeardedyorkshireman]

Sorry I didn't join in the post over the weekend, busy driving a mini digger in the garden!
I do not remember the ammendments calling for detection to work when you remove a head, but in practice most conventional detectors will be capable of generating an alarm in the event of removal of a single detector. You could calculate for each zone the theoretical probability if you had the panel terminal voltage, the alarm current threashold, the individual cable resistance head to head, diode and EOL spec, and head alarm current. Using kirchoffs you could then calculate a number of scenarios where the detection would/ would not work. Easier to say the callpoints should work and leave it at that, otherwise you would have to rethink conventional panel technology.
Has lucky been recaptured?  Good post!
PS please dont go around unplugging heads because one day my friends you will unplug a Vigilon head and then the world as we all know it will come to an end. ( before anybody asks, you have to go into the software and stop the loop BEFORE you touch it or it will probably CRASH!!)
Dave

[kurnal]

The world has already ended. It ended when I took over the building with the vigilon panel and started trying to make sense of the menu and configuration. Thats when I was admitted to the home. And they wont let me out till I have mastered the manual. Everytime it breaks I try to hit it with the big hammer but it still doesnt work so I end up having to pay someone else £350 per day to hit it with  their big  hammer, they hit it just like I did but they seem to make it work.

Try disabling a device on a loop and then trying to find which one it was to re-enable it later. Every vigilon panel should come with a memo board built in!

If you are suffering from kirchoffs and sneezes a sharing a hot toddy with matron can work wonders.

[lucky]

A drop in current would indicate a fault,so the system may activate.

[lucky]

Oh here is my night time medication,until tomorrow,zzzzzzzzzzzzzz

[Allen Higginson]

A drop in current would indicate a fault,so the system may activate.

You've lost me there??

[Allen Higginson]

The world has already ended. It ended when I took over the building with the vigilon panel and started trying to make sense of the menu and configuration. Thats when I was admitted to the home. And they wont let me out till I have mastered the manual. Everytime it breaks I try to hit it with the big hammer but it still doesnt work so I end up having to pay someone else £350 per day to hit it with  their big  hammer, they hit it just like I did but they seem to make it work.

Try disabling a device on a loop and then trying to find which one it was to re-enable it later. Every vigilon panel should come with a memo board built in!

If you are suffering from kirchoffs and sneezes a sharing a hot toddy with matron can work wonders.

Does the printer not work ob your Vigi's??Now,if you want a panel that is really good for isolation mystery try the Menvier (defender 4000?) - if you are not sure if your isolation worked and you do it twice (or moe) it logs that as two (or more) isolations.Add this to the ones you have already done it can become a pain.

[kurnal]

All the log tells me is that devices were disabled/ enabled in loop x. And it only counts 1 per loop irrespective of how many I disable. It often gives me fault messages that arent in the book. Still the hammer finish looks attractive in some lights.

[Wiz]

A drop in current would indicate a fault,so the system may activate.

Welcome back Lucky! Now that I have established that you really are a fellow resident of The Home For The Bewildered, I also now appreciate that there are different levels of bewilderment and you have obviously stumbled into this room by mistake.

But watch out, Matron is on the prowl looking for whoever keeps nicking the leftover food. I've told her that she should suspect the Hairy Monster From The North, who is a recently arrived fellow resident and has a very bad case of oral expectorations (according to long-time resident, The Kurnal) but she strongly suspects YOU since the incident with the roll. It has also been reported to her that you have started imagining seeing dinosaurs and I overheard 'them' talking about increasing your medication. Be careful about upsetting 'them'. Long time resident and agitator, CT, tried it a few months ago and no-one has heard from him since!

Finally, If you are considering a 'fault' as an 'activation' then you would be right.

I am now also considering the possibility that your posts are actually in code. I look forward to your next message.

Got to go now. See you at the 'movement to music' class tomorrow.

[kurnal]

Wiz you have missed the point. I have a theory.
Lucky IS the leftover food. You cant resist to pick at him then he gives you indigestion and keeps repeating on you.

[Wiz]

Wiz you have missed the point. I have a theory.
Lucky IS the leftover food. You cant resist to pick at him then he gives you indigestion and keeps repeating on you.

Kurnal, there are many that say you are a 'tough nut to crack'. But once again your Wiz-dom is spot on! I'll be moving to a new part of The Home shortly, hopefully Lucky won't be able to climb the stairs and find me, so I'll have nothing to nibble on and will then be free of my stomach pains (actually, they are mostly brought on by belly-laughs!)

[Wiz]

Everytime it breaks I try to hit it with the big hammer but it still doesnt work so I end up having to pay someone else £350 per day to hit it with  their big  hammer, they hit it just like I did but they seem to make it work.

Breakdown of £350 invoice:

             Hitting with big hammer     -    £  10.00
             Knowing where to hit         -    £340.00

[Wiz]

Therefore the conclusion reached for my original questions are:

              1) It has never been a recommendation of BS5839 Part 1 that automatic fire detectors need to continue working        
                  when other afd are removed

              2) No one knows why they shouldn't be included, since it is technically possible to do so.

I am now moving rooms within The Home. I'll be a bit busy whilst moving my bag of shottky diodes and book explaining Kirchoffs First Law (what goes in must come out).

However you are all invited to a house-warming drink in my new room later this week where I will take the opportunity to ask you all searching questions about beam detection.

Don't tell Lucky of my plans.

RSVP