Marking of fire alarm cables

[Baker1988]

Hi just a quick question, I'm currently working installing fire cable for a fire alarm circuit in a warehouse and I have been pulling them in according to the drawing, it has smoke detectors and sounder bases and has some interfaces aswell for the roller doors (think so they close if there is a fire to stop the spread). basically my question is the supervisor came down today and said to me have I marked the in and out on the cable so we know which one is which? I had not marked them in and out just the circuit and point number as I did not know I was suppose to mark them. I'm just not sure why they need to be marked in and out as they are just a loop go in one side of the break glass/sounder and out the other so what difference is in or out gonna make its still gonna go in one side and out the other and its a loop so both ends of the loop will be in the breaker so what difference would this actually make? Sorry if it sounds a bit dumb but I have never done a fire alarm on this scale before.

 

[telectrix]

a lot of smoke detectors require the in and out cables to be wired the correct way round. if they don't, there no need to ID the cables as in a nd out.

 

[Toneyz]

Don't usually have to if loop system but it is good practice to do so should there be a fault or additions need to be made it is also good to do a sketch on a drawing of the cable route and device seqence.

 

[telectrix]

sequence even. gor. we still educating these southerners. and us northen lads are supposed to be the thickos.

 

[Toneyz]

yes I know my spelling is ---- this is exactly why when I joined the forum for about a year I did not post anything I didn't think it was a spelling test

 

[telectrix]

haha, was only winding you up.

 

[tazz]

In and Out cables are only used on conventional systems, the reason is to identify detector removal, whilst continuing the circuit via the diode. So cable In & out is vital to continue operation of the zone circuit. There is no cable in & out on addressable systems as both cables are shorted on the base terminals throughout the loop. Full as fitted drawings are a requirement of BS5839 and BAFE install & commissioning.

 

[Leesparkykent]

In and Out cables are only used on conventional systems, the reason is to identify detector removal, whilst continuing the circuit via the diode. So cable In & out is vital to continue operation of the zone circuit. There is no cable in & out on addressable systems as both cables are shorted on the base terminals throughout the loop. Full as fitted drawings are a requirement of BS5839 and BAFE install & commissioning.

Hi tazz, I was wondering this myself after seeing this thread. I was fitting some Apollo XP95 isolator bases the other day and they were marked + and - in and out. Would it matter on these bases if you got them the wrong way round?

 

[tazz]

There actually called short circuit isolators, and basically open the negative terminals if they are not powered/shorted. Its not to important again as the loop is powered from both directions, but good idea to know which direction the loop is going. The idea is there should be a isolator every 20 detectors or per zone. if a cable goes down or a fault occurs the isolator before and after will o/c. As the loop is powered in both directions, the detection before and after the fault, continues to operate keeping the sounders etc continuing to operate.

 

[fattony]

there are only a limited number of addressable panels (that I've worked with) which require the in and out to be correct, Gent and Menvier, if its a Kentec, Advanced or Morley (run of the mill panels) they they do not need it but it would assist fault finding.

Conventional always require the in and out correct way round due to the diode

 

[Leesparkykent]

there are only a limited number of addressable panels (that I've worked with) which require the in and out to be correct, Gent and Menvier, if its a Kentec, Advanced or Morley (run of the mill panels) they they do not need it but it would assist fault finding.

Conventional always require the in and out correct way round due to the diode

Out of interest what do you think of the kentec gear? A office refurb we've just won has had a kentec addressable panel and Apollo short circuit isolator bases specified.

 

[fattony]

Out of interest what do you think of the kentec gear? A office refurb we've just won has had a kentec addressable panel and Apollo short circuit isolator bases.

Kentec and apollo isn't bad bit of kit, I think the panels have a 3 year warranty but if there is any cause and effects then Advanced is better.

Assuming your Kent based if you need any work done in this warehouse drop me a pm, we work closely with electrical contractors on a supply & commission basis quite frequently

 

[Leesparkykent]

Kentec and apollo isn't bad bit of kit, I think the panels have a 3 year warranty but if there is any cause and effects then Advanced is better.

Assuming your Kent based if you need any work done in this warehouse drop me a pm, we work closely with electrical contractors on a supply & commission basis quite frequently

Yes mate the job is in Whitstable. All the gear has been brought for the job Kentec panel and Apollo XP95 combined smoke/sounders. There is about 75 points and been wired in two loops as it was the most convenient way to do it due to how the job was staged/run. Hand over is the 22nd of December so got to be out before then if you would be interested in doing the commission?