How To Test Intruder Alarm

[james.wilson]

Possibly

[datadiffusion]

Just realised, can we chop and move to trade, sorry?

 

I would like to carry on and (if someone will show me how) upload a typical report and see what people think...

[james.wilson]

Id just start a new thread in trade. If you click on more reply options it will allow you to upload certain file types ie jpg etc

[arfur mo]

the basis of checking each cable go's back to single and double pole days. tbh most would take readings and compare to original site readings, if they altered then they would (should) investigate.

you have to figure it was miles of lace wiring often under hardboard, tube and batten frames, foil and door contacts often all on the same zone, any dampness would show and if severe enough short the two poles resulting in a lower voltage and risk of false alarms, earths could result in a zone being bypassed.

to that end you had a max limit of 22 ohms per pole and 2 meg minimum resistance. you can see a slight increase in resistance of a few ohms could be really troublesome. among the first tests is meter between 12 volts and earth on DC to look for insulation issues, most panels had chassis and negative rail down to earth, so you had to pull the earth before testing negative to earth.

[matthew.brough]

Before my time arf

[Amps]

the basis of checking each cable go's back to single and double pole days. tbh most would take readings and compare to original site readings, if they altered then they would (should) investigate.

you have to figure it was miles of lace wiring often under hardboard, tube and batten frames, foil and door contacts often all on the same zone, any dampness would show and if severe enough short the two poles resulting in a lower voltage and risk of false alarms, earths could result in a zone being bypassed.

 

 

So if the readings used to be taken with the devices still connected, when did it change to taking readings of the cable only?   

[arfur mo]

Before my time arf

reasons for a lot of what we do are cast over time, wether companies do this on shopping centre/shed systems i'd doubt, as it would likely take days to go to each expander and each zone.

Different and more advanced technology makes this thoroughness perhaps less requisite, your rarely going to get a short to earth on a pir as example, unless water damage from a leak in the roof or flooding, but having the initial installation readings if your sent to look at especially an intermittent fault on a door circuit it can be a real aid in the diagnosis of it,

Take carpet fitter or rodent damage as a prime examples, their very sharpe knives/teethe will slice the insulation perhaps short momentarily but not completely sever the cores within it. Depending on environment humidity i've known it take years for such damaged cable so exposed to corrode in a house.

if i go to a fault and can not detect what caused it, i remain suspicious of the user but i'll note down the readings for any later comparison.

[arfur mo]

So if the readings used to be taken with the devices still connected, when did it change to taking readings of the cable only?   

tbh likely due to less use of lace wiring and tube & batten frames, another factor is if a wire got broken, calling an engineer to repair would be expensive. as happened especially in clothing trades, patterns or garments would be hung off the alarm bars and client would often make a bad intermittent repair (rot) themselves - coining the term "Rot traced to FFHJ on cutting room window" (Found Fish Hook Joint) on site card note.

[andy82]

What I want to know is how do check for induced ac current, total load for battery

To check ac induced set the meter to ac then connect between mains earth and +12Vdc on panel any reading above about 0.6 Vac should be dealt with you can install a 12v spike suppresor (act make one i belive its act1313)

As for total load connect meter in series with battery set meter to current then drop mains, record the reading for normal operation, then set bells off that will then give you the current in alarm state

Hope this helps

[Amps]

As for total load connect meter in series with battery set meter to current then drop mains, record the reading for normal operation, then set bells off that will then give you the current in alarm state

 

 

Does the battery have to be fully charged for this reading?