Analogue value

[Benzerari]

Analogue values are not defined in a British Standards. The digital numbers an addressable device generates are representations of the various conditions that that device can find itself in. These digital numbers can be different from manufacturer to manufacturer, and from range to range. That an analogue value of 60 in Company 'A's range might represent the point that should represent a fire condition, the equivalent point in Company's 'B's range might be an analogue value, of say, 45. It is up to the control equipment to be designed to respond correctly to the various analogue values.

I though it must be some reference to what the analogue addressable systems are designed respond to, for smoke detectors readings for example it must be some reference in percentage of obcusration or number of particules in a square mm:

Just as an example:

From: 1%      To: 9% ---------------> Faults condition or ( No reading received )
From: 10%    To: 40% --------------> Normal condition
From: 41%    To: 49% --------------> Prealarm condition
From: 50%    To: 55% --------------> Fire condition

etc...

Am I making sense ?

I trust the following is an answer to your question.


I think you will find that response levels to smoke, heat etc. are determined by various Standards, for example, the Apollo XP95 ionisation specification mentions sensitivity as being to EN54 Pt 7 1984; (BS 5445 Pt 7 1984).

Wiz; I need either a link or a PDF copy of the doc stated above; I want to know the response levels to smoke, heat determined by these various standard...

Any help would be appreciated

[JonnyG]

Very interesting read Wizz!!

Just another question for the BS buffs. Is there anything that states how far a threshold can be moved to avoid pre-alarms etc.

I know on Morley's that you can only move the thresholds so far, but is this part of BS?

[Galeon]

There are a few addressable panels still on the go that use addressable bases with conventional heads.
The base can only report,the address,fire and fault conditions and has no idea of what the condition of the detector is in.

Most popular i have seen is an addressable base with Hochiki heads.

Can you tel me what versions of Hochiki detectors with addressable basis? because the only Hochiki detectors I have seen up till now are the heads that uses their current basis and in witch the heads are addressed electronically using Hochiki address machine ?

The older version Hochiki was HRE Protocol (Latest is ESP which you describe).
HRE was with dil switches in the detector , the same as Apollo Series 90 therefore Analogue Addressable , and CDX range being addressable base (basically stripped down version ) with the ability to be addressable only with a conventional detector used.

[Wiz]

Very interesting read Wizz!!

Just another question for the BS buffs. Is there anything that states how far a threshold can be moved to avoid pre-alarms etc.

I know on Morley's that you can only move the thresholds so far, but is this part of BS?

I don't know the specific requirements/recommendations because I am not a detector manufacturer.

I would imagine that there must be a 'window' for the sensitivity recommendations and possibly the Morley thresholds move within this 'window'

However, on Ampac panels it appears that you can move the thresholds by an amazing amount. I don't know how this ties in with BS recommendations but I would imagine it exceeds any 'window'

BS 5839 Part 1 is my speciality. I don't know the other recommendations in as much depth. Possibly BS EN54-7 will contain the information you require. But I would first suggest talking to detector/panel manufacturers to get pointed in the right direction.

[fuzzy]

Also, it will be worth noting, on many addressable systems, the analogue value threshold can be set at the panel usually through day/night settings.

edit: Should read the whole topics before replying.

[Benzerari]

Hi all;

Analogue addressable detector has analogue value and it reports it to the FAP when interogated, and that analogue value is readable to. but does conventional detector have analogue value too which is not just readable. if yes, is the decision of either normal or emergency situation made by the detector it self or by the panel? in either conventional and analogue addressable technologies?

Thank you in advance.

Benzerari

After while, I can confirm conventional detectors doesn't have analogue values, such as analogue addressable ones, they trigger only if the threshold level is reached... they have no communication between them and the main the panel at all. they are passively sitting in the detection circuit as a waching dog.

[Wiz]

After while, I can confirm conventional detectors doesn't have analogue values, such as analogue addressable ones, they trigger only if the threshold level is reached... they have no communication between them and the main the panel at all. they are passively sitting in the detection circuit as a waching dog.

I take it from this Benzerari, that you didn't believe us when we originally told you!

[Graeme]

i would hazzard a guess on that

[Benzerari]

After while, I can confirm conventional detectors doesn't have analogue values, such as analogue addressable ones, they trigger only if the threshold level is reached... they have no communication between them and the main the panel at all. they are passively sitting in the detection circuit as a waching dog.

I take it from this Benzerari, that you didn't believe us when we originally told you!

Remind me please when did you say that?

[Benzerari]

After while, I can confirm conventional detectors doesn't have analogue values, such as analogue addressable ones, they trigger only if the threshold level is reached... they have no communication between them and the main the panel at all. they are passively sitting in the detection circuit as a waching dog.

I take it from this Benzerari, that you didn't believe us when we originally told you!

Also I do appreciated all adds in this issue

[Wiz]

After while, I can confirm conventional detectors doesn't have analogue values, such as analogue addressable ones, they trigger only if the threshold level is reached... they have no communication between them and the main the panel at all. they are passively sitting in the detection circuit as a waching dog.

I take it from this Benzerari, that you didn't believe us when we originally told you!

Remind me please when did you say that?

I came into the debate long after pfd-chris wrote on 8/2/07   Conventional devices and analogue addressable work in very different ways...   ....With conventional devices, the device does the 'deciding' the panel is just looking for the end of line and fire resistor being shorted across (which the detector does)...... By this time I presumed that this bit was clear to you and just answered your questions about the analogue values of addressable systems.

[Benzerari]

I take it from this Benzerari, that you didn't believe us when we originally told you!

Remind me please when did you say that?

I came into the debate long after pfd-chris wrote on 8/2/07   Conventional devices and analogue addressable work in very different ways...   ....With conventional devices, the device does the 'deciding' the panel is just looking for the end of line and fire resistor being shorted across (which the detector does)...... By this time I presumed that this bit was clear to you and just answered your questions about the analogue values of addressable systems.

That's what pfd-chris wrote:

Conventional devices and analogue addressable work in very different ways... A addressable device usually just reports its reading to the panel and the panel decides (you may have notices bedroom , office modes etc that allow for higher readings without generating an alarm state, one further -  discriminating algorithm technology depends on the type of panel and compatible detectors, software in the panel looks at the characteristics and comparing changes in the values being sent to the panel before doing anything)

With conventional devices, the device does the 'deciding' the panel is just looking for the end of line and fire resistor being shorted across (which the detector does)

if im wrong on anything , feel free to correct me

That's right just things take longer to get into...,  probably because of my slow timer and/or low speed microprecessor...

[wozzer38]

Very interesting read Wizz!!

Just another question for the BS buffs. Is there anything that states how far a threshold can be moved to avoid pre-alarms etc.

I know on Morley's that you can only move the thresholds so far, but is this part of BS?

From a course I was on at Apollo, the XP95 detectors give an alarm value of 55 which is equal to 2.4% light grey smoke obscuration per metre.

It is possible to change the alarm threshold so that the alarm Analogue Value would need to reach, say 60 when 2.4% smoke was in the detector, making the device (artificially) less sensitive. Or if you made the threshold 50 it would be more sensitive.

I was told doing this on an XP95 system takes the detector out of its EN54 Pt7 approved level. And if this is done then a deviation should be made on the system paperwork.

However, they said that if you use Discovery detectors and change sensitivity modes, all the modes are approved already so changing them doesn't cause any issues.

[Wiz]

That's right just things take longer to get into...,  probably because of my slow timer and/or low speed microprecessor...

I know the feeling well Benz. I'm expecting my own timer to cut out completely at any time.

[Benzerari]

That's right just things take longer to get into...,  probably because of my slow timer and/or low speed microprecessor...

I know the feeling well Benz. I'm expecting my own timer to cut out completely at any time.

I though only me?    

Don't tel because of the recession combined with the age?  we may lose the morgage or have one meal a day? to survive, hopefuly Russia wouldn't worsen things more and more... as tax payers we have already lost a lot in......