20 replies to this topic

[divad]

I had the usual problem of the bell going off when there is a power cut.

I replaced the backup battery and checked the fuse.

My supplier sold me a 12V 2.2AH battery saying it would be ok even though the original battery was a 2.8ah and the recommended was 7ah.

The bell still goes off when the power fails and the battery is still giving out 12.6 volts.

The system is an intellisense 800L

So is the problem the battery? or is it the board? Or is it me?

Help appreciated.

[Mr Marco]

divad, on 14 June 2011 - 12:23 PM, said:

I had the usual problem of the bell going off when there is a power cut.

I replaced the backup battery and checked the fuse.

My supplier sold me a 12V 2.2AH battery saying it would be ok even though the original battery was a 2.8ah and the recommended was 7ah.

The bell still goes off when the power fails and the battery is still giving out 12.6 volts.

The system is an intellisense 800L

So is the problem the battery? or is it the board? Or is it me?

Help appreciated.

Have you checked to see if the battery link is fitted in the SAB? Check between trigger and +ve terminals when in alarm. Have you got voltage? The trigger should 'go low' in alarm. You should be able to locate the problem to the panel or the SAB this way. Hope I'm not teaching you to suck eggs...

Mr Marco, on 14 June 2011 - 01:08 PM, said:

Have you checked to see if the battery link is fitted in the SAB? Check between trigger and +ve terminals when in alarm. Have you got voltage? The trigger should 'go low' in alarm. You should be able to locate the problem to the panel or the SAB this way. Hope I'm not teaching you to suck eggs...

Okay so I re read the original post...

When you say 'goes off' do you mean the SAB sounds when you drop the power to the panel? Does the SAB sound when in alarm with the power on? Does the panel stay powered up running on the battery when you ditch the mains? If not this would point to the battery fuse having blown.

[divad]

Sorry not to be clear on this one.

Don't worry about sucking eggs. I'm a novice. Assume I know nothing.

1 The SAB (self activating bell) sounds during a power cut and only when the power is cut or in an alarm.
It hasn't as far as I know always done this.

2. With power on and in alarm the SAB sounds

3. With the power off and in an alarm I don't know if there is power to the panel there is certainly no power to the key pad.

Thanks for helping

Edited by divad, 14 June 2011 - 02:37 PM.

[MrHappy]

remove the battery frpm the battery leads & measure the output ?

[Mr Marco]

Im with Mr Happy on this. I would check the battery first then using a meter check for a charging voltage coming from the panel across the battery leads (while the batt is still disconnected). It deffo sounds battery related as the keypad should still stay lit even with just the battery and no mains. There is a good chance that when the old battery died it blew the battery fuse and if this isn't replaced the battery is effectively disconnected. Use a meter on Ohms scale to test the fuse (out of its holder!).

[divad]

The voltage from the battery is 12.6V

I'll test the fuse again tonight.

[Mr Marco]

Did you get a voltage across the battery leads (battery disconnected)?

[breff]

Battery fuse or damaged charging circuit, test voltage at battery leads with battery disconnected

[Mr Marco]

Forgot to mention the Ah rating of batteries. Ah stands for Amperes Per Hour and its rating tells you, in an ideal world, how many Amps of current the battery can supply per hour. As a very rough calculation if for instance your system (panel + detection + sounders and anything else connected) is drawing 500mA (half an amp) from the supply, then a 7 Ah battery should run your system for 14 hours. This doesn't take into account any changes in current drawn by the system or drop in voltage supplied by the battery. I've seen a correction factor of 0.7 applied to take some of these variables into account and as such would return a standby time with a 7Ah battery of 9.8 hours (7Ah/500Mv) x 0.7 = 9.8 hours. These calculations are just a guide and there are other factors to take into account especially with a signaled system. this forum has a good resource for calculations here..

http://www.thesecuri...sia-techmaster/

As with any rechargeable battery this rating will drop over time hence the requirement to test batteries as part of a service visit. Don't forget that a battery straight off the shelf will need to be fully charged by the panel before achieving its rating as it could have been sat in a box for months.

So to recap, check for voltage across the battery leads (should read around 12v). If that voltage is okay you should be able to discount the battery fuse as being at fault. It could be the case that you have a faulty battery, its not unknown.

Edited by Mr Marco, 14 June 2011 - 06:00 PM.

[Mr Marco]

breff, on 14 June 2011 - 05:32 PM, said:

Battery fuse or damaged charging circuit, test voltage at battery leads with battery disconnected

As Breff says even if the battery fuse is okay there is a possibility that a component has failed in the battery charging circuit on the PCB. although repairable I would recommend replacing the PCB (unless you are hiding your electronic fault finding and PCB repair skills from us!)

[9651]

That reminds me, need to get my ACT battery tester looked at, fails every battery i try lol!

(not bad thing? ) (Jokes)

Edited by 9651, 14 June 2011 - 06:18 PM.

[Mr Marco]

9651, on 14 June 2011 - 06:17 PM, said:

That reminds me, need to get my ACT battery tester looked at, fails every battery i try lol!

(not bad thing? ) (Jokes)

My red and gold one did exactly the same thing and I bet it wasn't 6 months old either. 'Inherited' and older black and gold one off a retiree that seems okay!

Edited by Mr Marco, 14 June 2011 - 06:25 PM.

[9651]

Aye, this is a red'un. Had it years. Find it strange NSI want multi meters calibrated, but aint fussed on battery testers?

[Mr Marco]

9651, on 14 June 2011 - 06:32 PM, said:

Aye, this is a red'un. Had it years. Find it strange NSI want multi meters calibrated, but aint fussed on battery testers?

Yeah very odd. Can the ACT ones be calibrated? They look like a sealed unit to me

[9651]

i've had mine apart when i got the lead stuck and pulled it clean off the pcb

Probably why it doesnt work any more

[magpye]

Mr Marco, on 14 June 2011 - 06:44 PM, said:

Yeah very odd. Can the ACT ones be calibrated? They look like a sealed unit to me

Yes they can.

The Calibration Kit is a new pair of leads (because the old ones break down)

[sixwheeledbeast]

9651, on 14 June 2011 - 06:17 PM, said:

That reminds me, need to get my ACT battery tester looked at, fails every battery i try lol!

Nearly bang on every 12 months my Red IBT fails all 7Ah batteries until it's gone back to ACT for a service.
As mentioned possibly to do with the leads breaking down.
As good as new when it comes back from Rainford tho.

[magpye]

sixwheeledbeast, on 14 June 2011 - 11:59 PM, said:

As mentioned possibly to do with the leads breaking down.

No possibly about it, never looked for the answer on the ACT site?

[sixwheeledbeast]

magpye, on 15 June 2011 - 06:13 AM, said:

No possibly about it, never looked for the answer on the ACT site?

Nope, I actually meant to say probably. But it seems there's "no probably" about the subject anyway.

The point is they need servicing regularly to be as accurate as possible.
It can be done and they do a good job of it.
IBT Calibration Kit

[divad]

Back to the problem with the alarm!

I checked the fuse and it had blown. I feel very silly because I had checked it when I fitted the new battery and it was ok. I should have checked it again. I've replaced the fuse and its definitely charging the battery now. I'll let you know if this solves the problem.

This saga has prompted a few more questions

If I wanted to replace the circuit board, are they available as a spare part - I can't find any supplier on the internet?
How do I isolate the power to the board without the SAB sounding? Which I would want to do if I fitted a new pcb or board.
If I fitted a new panel given that all the wires are in place are there any major snags? What would be the most difficult bit? Would I need to replace the keypad or are they all interchangeable?

Thanks guys.

By the way my tester failed failed too. It was only a Maplins cheap one but it hadn't been overused. Clearly they aren't made to last.

My wife says it would be simpler to just let the bell ring on the rare times there is a powercut. Lots of other alarms go off when this happens anyway.