Fire Alarm Systems

[joe_berks]

Hello everyone .

I have recently started a new job which involves testing fire alarms, and the subsequent remedials, mainly in pubs.

I'm a sparks with 2391 and 17th and I've done it since I left school, I'm 28 now . I hadn't had much to do with fire alarms before now , but I find the testing side fairly straightforward as long as you have the codes etc . My question though relates to the smoke heads ... most of them are menvier , cooper or jsb . But they all seem to have different connections that confuse the hell outta me , even though its only two twin cables ! Are all smoke heads interchangeable ? I dont know where I'm going wrong , I change the smoke head for a new one and follow the diagram that comes with the detector, but it sometimes shows fault on the panel after I have fitted it ?! And also where does the EOL resistor go because I have seen it across L's, L+N, and N's

I know someones gonna start saying I'm going to end up in court etc because I'm not a fire alarm engineer but all I can say is I am believe it or not a competent person !

Any input would be much appreciated .

 

[Andy78]

You have just started a new job you state. Should your employer not be the first one to go to with concerns of a lack of knowledge or training concerning the tasks you are being asked to carry out ?

 

[tazz]

There are a few different issues here and hard to go through them all, as experience is the only answer.....
Menvier are negative diode remove detection, apollo and most others are positive diode remove detection.
JSB, twinflex and twinwire are all different wiring methods and system types, thus are non interchangable
And end of line unit, is again dependent on the system used, can be a resistor, cap or active circuit.
A full test kit such as solo, is require along with correct battery tester to conduct a correct service test.

 

[Matth]

Hello everyone .

I have recently started a new job which involves testing fire alarms, and the subsequent remedials, mainly in pubs.

I'm a sparks with 2391 and 17th and I've done it since I left school, I'm 28 now . I hadn't had much to do with fire alarms before now , but I find the testing side fairly straightforward as long as you have the codes etc . My question though relates to the smoke heads ... most of them are menvier , cooper or jsb . But they all seem to have different connections that confuse the hell outta me , even though its only two twin cables ! Are all smoke heads interchangeable ? I dont know where I'm going wrong , I change the smoke head for a new one and follow the diagram that comes with the detector, but it sometimes shows fault on the panel after I have fitted it ?! And also where does the EOL resistor go because I have seen it across L's, L+N, and N's

I know someones gonna start saying I'm going to end up in court etc because I'm not a fire alarm engineer but all I can say is I am believe it or not a competent person !

Any input would be much appreciated .

Not all heads arew interchangeable, the way they are wired depends more on the panel being used. Also if analogue of addressable.


again EOL depends on what panel manufacturer.........


I would get your employer to give you some training on fire alarms, because at the end of the day if there is an issue with the fire alarm, it wont matter how many electrical qualifications you have, if you have caused a system to operate incorrectly, your --- will be on the line. Agood employer will have no issue with a bit of training.

 

[tazz]

Not quite true....polarity or diode reverse can be used to correct a change of devices in certain cases.
The op is commenting on conventional systems here, hence eol.
But as with any system, addressable or conventional, they are all work on much the same basis and can be fully changed, using existing cable or loop configuration.

 

[thekingiam]

Tazz is d man

 

[dingledong]

Yes he is rather good isn't he

 

[Diddy]

Done fire alarm systems till they started haunting me in my dreams lol. As said though the best way to get some knowledge of these systems is to shadow an experienced person for a few weeks. That will give any experienced spark the knowledge they need to get on with it. That said we always tested in pairs anyway.....so really shouldn't be a problem for your new employer.

 

[joe_berks]

Thanks for the replies everyone . Yes they have issued me with a full solo kit . I shadowed a guy for a week and picked up a lot . I will definitely ask to go on a course . I was completely honest at interview , told him although I've done a lot of the fixed wire testing side of things , but never done much in the way of FA's.

 

[joe_berks]

So I guess the answer is that yes, any conventional smoke head can be changed but the wiring configuration may differ ?

 

[joe_berks]

Gotta say , some of the time I'm ****ting it , hoping the panel don't start howling lol . Also I want to say to my manager that in some of the premises its just not practical to ring the bell 80 times in an occupied travelodge for example , suggest disconnecting the sounders and having another man at the panel checkingit went to fire mode when a detector is tested ... is that a legit call ?

 

[tazz]

All control panel have disabled function, so you can program the panel to disable sounders. And basically do a silent test.

 

[joe_berks]

Yeah but if im at the smoke head and even if the red led comes on that doesnt necessarily mean the panel will have gone into fault as i understand it , so another man needed at panel for ease do you think ?

 

[tazz]

The panel will still show zone fire, but no bells or sounders will activate....if also programmed for test, the panel will reset automatically after 4-5 seconds, saving you running back to the panel all the time.

 

[joe_berks]

The panel will still show zone fire, but no bells or sounders will activate....if also programmed for test, the panel will reset automatically after 4-5 seconds, saving you running back to the panel all the time.

Yeah I always put the panel into test . But what Im saying is if the detector is on the top floor for example , unless you have sounders on , or someone at the panel to confirm fire at the panel , you're going back down to check the panel has gone to fire mode (?) i.e a red led at the smoke head is not sufficient enough to confirm its compliant

 

[joe_berks]

Plus , as you say , it resets after 5 seconds . So you gotta run downstairs super quick to see if the panel has responded

 

[tazz]

I understand what your saying, but fire system are built to monitor the detection circuit, so if no fault is showing on the zone, then it has no o/c and no c/c. And if when tested the led is lite. then proof of supply and cable have been proved

 

[joe_berks]

I understand what your saying, but fire system are built to monitor the detection circuit, so if no fault is showing on the zone, then it has no o/c and no c/c. And if when tested the led is lite. then proof of supply and cable have been proved

Oh right , fair enough , if thats the case then i will do silent tests from now on , obviously i'll do a sounder test in each zone to prove they work first haha . cheers tazz . You are indeed the man

 

[ayjay]

why don,t u just change the heads like for like?
its simple
how do u test them btw?

 

[Poult12]

Tazz defo the man here Joe. I learnt the hard way!!!

Would also like to make a small point that on some addressable systems you'll be able to find a log inside the panel delict of what has gone off while in test mode so you could confirm which have definitely gone off for your own piece of mind (obviously not on conventional systems).

Some addressable systems also have a printer on the front - such as an Advanced panel this also confirming a fire state.