Fault On Pir

[arfur mo]

Hi guys i wonder if any of you have come across this problem before i had a customer call out for a fault on a PIR it just went into alarm when he was at home one day. I checked the wire all fine i didnt change the PIR, Not one in the van so i just turned off the zone 3, four hours later get a phone call same thing happened again zone 2. Both PIR are on the same run of wire. any ideas please.

i'd need to clear up was the system on in part set, or was this a 'daytime' tamper?

a tamper is more likely to be a lid contact on aj/b perhaps or as others say cable damage, carpet fitter or rodents main suspects.

if it was set might be the power rail problem or week battery, 'walking faults' where the zone alarmed changes can be due to this problem or possibly earths on the system.

if it's the supply thats at fault you have to bear in mind pirs have nominal voltage working levels, both high and low limits. say you have a duff supply and 4 "Maker X" pirs, each will work down ot a stated voltage level, after which they will d'rop out' at a slightly different voltage level to each other.

now lets say all will work down to 10.8 volts, if the battery discharges on mains off, the volts will drop gradually to a point below that level, so say now Z2 triggers being the most senitive due to component spread. you replace or disconnect it as you have done and a while latter Z4 plays up. now your scratching your head because the panel only shows the 1st to alarm perhaps - but was not 'on' long enough to show other zones would most likely also have tripped eventually.

the aboves not the only example, but in a format to best explain overall, and an often overlooked facet by the less experienced service engineers to look out for.

check the aux volts are at a 13.6 ish! turn off the mains, keep meter attached and observe the voltage how far it drops, should no get below 12 volts, ring the sirens for a minute or so to draw off the batteries see how low it drops.

check the voltage at the detector/s at this stage before restoring the mains, 10.8 i think is the 'official' minimum but i's be concerned at anyting below 11.10. check again after restoring the mains for over voltage, should be 13.00 - 13.65 ideally at the detector, but best below 13.9 as many detectors are rated at 14.2 max

hope it helps.

regs

alan

[Guest anguscanplay]

i'd need to clear up was the system on in part set, or was this a 'daytime' tamper?

a tamper is more likely to be a lid contact on aj/b perhaps or as others say cable damage, carpet fitter or rodents main suspects.

if it was set might be the power rail problem or week battery, 'walking faults' where the zone alarmed changes can be due to this problem or possibly earths on the system.

if it's the supply thats at fault you have to bear in mind pirs have nominal voltage working levels, both high and low limits. say you have a duff supply and 4 "Maker X" pirs, each will work down ot a stated voltage level, after which they will d'rop out' at a slightly different voltage level to each other.

now lets say all will work down to 10.8 volts, if the battery discharges on mains off, the volts will drop gradually to a point below that level, so say now Z2 triggers being the most senitive due to component spread. you replace or disconnect it as you have done and a while latter Z4 plays up. now your scratching your head because the panel only shows the 1st to alarm perhaps - but was not 'on' long enough to show other zones would most likely also have tripped eventually.

the aboves not the only example, but in a format to best explain overall, and an often overlooked facet by the less experienced service engineers to look out for.

check the aux volts are at a 13.6 ish! turn off the mains, keep meter attached and observe the voltage how far it drops, should no get below 12 volts, ring the sirens for a minute or so to draw off the batteries see how low it drops.

check the voltage at the detector/s at this stage before restoring the mains, 10.8 i think is the 'official' minimum but i's be concerned at anyting below 11.10. check again after restoring the mains for over voltage, should be 13.00 - 13.65 ideally at the detector, but best below 13.9 as many detectors are rated at 14.2 max

hope it helps.

regs

alan

or just look for any new carpets

[camerabloke]

bit of a bummer if he lives above a carpet shop

[Guest anguscanplay]

bit of a bummer if he lives above a carpet shop

LMFAO

[arfur mo]

or just look for any new carpets

your limited angus, your just so limited

regs

alan

[Guest anguscanplay]

your limited angus, your just so limited

regs

alan

wasted you mean LOL

though I think the O/P might have mentioned power fails in his original post always looking for the hard way you are

[arfur mo]

wasted you mean LOL

though I think the O/P might have mentioned power fails in his original post always looking for the hard way you are

not a panel i've seen,

many panels on a power up (after complete power down) will show the 1st zone it feels like showing as the 'alarm' fault.

engineers can be fooled by the 'its a computer so it must be right' syndome, bit like many blindly accept the bill is correct at the supermarket checkout because 'it was done by machine' - and get well screwed more often than not into the process.

anyway, hopefully others have taken on board the differing approaches and be a little wiser and better for it - or more likely a hell of a lot more confused

regs

alan.

[Guest anguscanplay]

not a panel i've seen,

many panels on a power up (after complete power down) will show the 1st zone it feels like showing as the 'alarm' fault.

engineers can be fooled by the 'its a computer so it must be right' syndome, bit like many blindly accept the bill is correct at the supermarket checkout because 'it was done by machine' - and get well screwed more often than not into the process.

anyway, hopefully others have taken on board the differing approaches and be a little wiser and better for it - or more likely a hell of a lot more confused

regs

alan.

ah I see - it was a different phase to the one the O/P`s customer was " at home to...." thats why he didnt notice the power cut then but your right about one thing - you do confuse the issue

[arfur mo]

ah I see - it was a different phase to the one the O/P`s customer was " at home to...." thats why he didnt notice the power cut then but your right about one thing - you do confuse the issue

i used 'power cut' used as a generic term, not to say the main house went out, i.e duff fuse/holder, dodgy joint in spur od mains block etc.

only one confused is you - but thats just par for the course. mind you, ideal situation to try out a brand new neon screwdriver

while we are on that subject, i walked into Senate Electrical today to buy some trunking, noticed they had to have had 50 or so neon drivers on display, and 3 different models to chose from + the hot finger version - and this is a profesional trade electricians wholesalers, so what say you?

regs

alan

[Alarm Co]

Hi guys i wonder if any of you have come across this problem before i had a customer call out for a fault on a PIR it just went into alarm when he was at home one day. I checked the wire all fine i didnt change the PIR, Not one in the van so i just turned off the zone 3, four hours later get a phone call same thing happened again zone 2. Both PIR are on the same run of wire. any ideas please.

checkd zones terminals on panel for induced ac voltage