Bell box sounds 10 mins after mains failure

[Kas]

Hi.

After isolating power to the workshop, some ten minutes or so later the bell box goes off.

With the mains still isolated, I checked the LCD display panel (Honeywell ADE Gen4) and found that it was fully functional, so still being powered by the main battery.

This battery was replaced two years old, so doubtful that this is the cause.

The bell box is a Honeywell AG6, and is just over five years old. 

All I can think is that the battery in the bell box is only kept charged while mains power is available at the panel, so once this is cut, does the bell box respond to it's own dwindling battery voltage by sounding the alarm?

Thanks, Kas 

 

[Richard-the-Ninth]

The idea of a panel standby battery is to power the whole system in the event of a power cut, so when you have a short powercut the alarm should work as it was, before the powercut. I would say either the panel battery is nearly flat, its not being charged or you have a blown fuse.

 

[Bruspark]

Odd as generally the bell box battery is continuously charged from the panel using mains or back up battery power and when the cable to it signals for it to ring or the cable appears to be disconnected or shorted etc it sounds using its own battery power alone (for c 15-20 minutes when new.)

It may be that the bell considers it has lost charge power from the panel at a higher voltage than the panel minimum working voltage (which could be a symptom of a poor connection on the charge wire). 
After checking the manual for any unusual programming options first step is to monitor the panel battery voltage with the mains disconnected remembering that 12V in standby from a panel Lead acid battery is pretty much flat . .
2 years is young for lead acid but they are often failing by 4 or 5 

 

[phil d]

Odd as generally the bell box battery is continuously charged from the panel using mains or back up battery power and when the cable to it signals for it to ring or the cable appears to be disconnected or shorted etc it sounds using its own battery power alone (for c 15-20 minutes when new.)

It may be that the bell considers it has lost charge power from the panel at a higher voltage than the panel minimum working voltage (which could be a symptom of a poor connection on the charge wire). 
After checking the manual for any unusual programming options first step is to monitor the panel battery voltage with the mains disconnected remembering that 12V in standby from a panel Lead acid battery is pretty much flat . .
2 years is young for lead acid but they are often failing by 4 or 5 

Those ACT battery testers are great as they give the battery voltage, temperature and % available capacity, I think they start from about £150, but worth having, I bought the ACT gold a few years ago.

 

[Richard-the-Ninth]

I get the impression the op will not be buying one of them.  A multi meter costs less and is better than an ACT test meter, all they are really good for is to make the person using it look good and showing a customer the battery is flat.

You are also supposed to let it "rise to room temperature" before you use it.

 

[phil d]

I get the impression the op will not be buying one of them.  A multi meter costs less and is better than an ACT test meter, all they are really good for is to make the person using it look good and showing a customer the battery is flat.

You are also supposed to let it "rise to room temperature" before you use it.

I can see you know very little about testing batteries, an ordinary multimeter does not put a load on the battery under test and therefore does not provide a true indication of battery condition. You can get a car battery that will read 12 volts on an ordinary multimeter yet will not start a vehicle, or even power the headlights. I suppose you think an oscilloscope has no place in fault diagnosis on alarm systems either.

 

[UNG]

I get the impression the op will not be buying one of them.  A multi meter costs less and is better than an ACT test meter, all they are really good for is to make the person using it look good and showing a customer the battery is flat.

All my multimeter's cost way more than ACT Battery Tester but guess what I still use an ACT Battery Tester.

Been using ACT stuff for many years, the guy that owns the company and designs all of it's products is a fault finding guru on alarm systems went to a few of his companies open days many many years ago when he first started up and learnt a lot of things about interference causing alarm faults and how to track it down

You are also supposed to let it "rise to room temperature" before you use it.

It's the same for all test equipment so you can't really use that as a problem

 

[Bruspark]

I hate to interrupt a good row but that's why I specified the 12V=flat  as being "mains disconnected . . in standby" (which usually means a discharge current of around a 0.1C discharge rate)  If it's fallen below 12 V in an hour or two it is definitely dud. . 

The little battery testers are cool but I couldn't justify buying one personally ..

 

[Richard-the-Ninth]

I still stand by what I said, but I will also say you  assume I check the voltage, I never said that did I. If you must know I check the current the battery is drawing when its being charged.

The original ACT battery tester was just a cigarette lighter in a box with a 3 stage voltage indicator, it caused more harm than good, which is why I gave mine back.

As for his other devices (in particular the ACT fault finding meter), yes, his name is on it, but no, he didn't invent it.