Fire alarm

[cristafar]

Hi, been servicing a fire alarm and in some areas the devices are sending 3 different zones into fire? The engineer I work with says this is a wiring fault somewhere, I was just wondering how this happens, it's a conventional c-tec 8 zone panel.

Thanks

Chris

 

[tazz]

Never come across this one before, Logically to activate 3 zones at once the + from all 3 zones must be shorted as they share a common - with all zones and sounder circuits. But can not see them all being shorted and would imagine a fault led on all 3 zones.
Can only suggest at this time to remove all cables from 2 of the effected zones, dont worry about end of line caps, they will just show faults on the zones. then test the 3rd zone and see if the other 2 zones go into fire condition. If they do then panel is at fault. Would suggest doing this test first to save a lot wasted time looking for wiring faults.

 

[telectrix]

Never come across this one before, Logically to activate 3 zones at once the + from all 3 zones must be shorted as they share a common - with all zones and sounder circuits. But can not see them all being shorted and would imagine a fault led on all 3 zones.
Can only suggest at this time to remove all cables from 2 of the effected zones, dont worry about end of line caps, they will just show faults on the zones. then test the 3rd zone and see if the other 2 zones go into fire condition. If they do then panel is at fault. Would suggest doing this test first to save a lot wasted time looking for wiring faults.

good thinking. i would suspect a panel fault.

 

[cristafar]

Thanks tazz, i think that is the best way forward to take out 2 of the zones and see if the panel still shows faults on the other 2 zones. the zones that are effected are 2 4 & 8 and there is no current faults on the panel so this really rules out wiring problems like u say above, the chances are slim to none. thanks for your advice tazz we are back there tomorrow and will update u on the outcome. thanks

 

[tazz]

Ok when you disconnect zones they will show fault, its fire activation where looking for, will be interesting to have your feed back on this problem
good luck Dave

 

[alarm man]

id also try puttng your eols in the zones,a fault on the zone might mask the problem,tho as tazz says its def the panel..