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Burglar alarm - power off?

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Dave

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Dec 3, 2009, 6:15:33 AM12/3/09
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What happens to a burglar alarm (just a stand-alone one, not centrally
monitored) when mains power is off for days? I know that the internal
battery will obviously discharge but does it actually trigger the sounder at
any point, or does it just die quietly?

We're going away for two weeks, during which time the house is being rewired
and I don't want the neighbours being disturbed by a shrieking alarm.

TIA


slider

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Dec 3, 2009, 6:24:35 AM12/3/09
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"Dave" <do...@bother.com> wrote in message
news:vs2dnaDvk_tOAIrW...@bt.com...

Once power is disconnected, the alarm will activate. Your external bell box
will most likely have a battery back up. The external box will sound until
either battery goes flat, or power is restored and alarm reset. Best option
is to enter the engineer code into the alarm (if you know it). This will
stop the alarm sounding when power is disconnected. Alternatively,
disconnect battery backup from both alarm panel and external bell box (not
sure, but this may wipe the alarms internal settings or it may have a small
watch type battery to retain settings).

What alarm is it?


Dave Liquorice

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Dec 3, 2009, 6:41:43 AM12/3/09
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On Thu, 3 Dec 2009 11:24:35 -0000, slider wrote:

> Once power is disconnected, the alarm will activate.

It shouldn't if the panels internal backup battery is OK. Damn thing
would sound if there was a power cut...

> Your external bell box will most likely have a battery back up. The
> external box will sound until either battery goes flat, or power is
> restored and alarm reset.

If the sounder has a backup battery (it should) then it will sound
when once the battery in the panel is flat after the loss of power.
It should also only sound for a few minutes then shut up but it might
sound until that bettery is flat.

> Best option is to enter the engineer code into the alarm (if you know
> it). This will stop the alarm sounding when power is disconnected.

Which shouldn't happen....

> Alternatively, disconnect battery backup from both alarm panel and
> external bell box

Without entering engineering mode when you open the cover of either
the panel or the sounder to disconnect the batteries it will trigger
the alarm.

So enter engineering mode, disconect the batteries. Leave the panel
powered up and go away leaving but remember that there will be no
alarm when the power is off. But one assumes that there would be no
alarm anyway unless you give a code to the workmen and trust then to
set it...

--
Cheers
Dave.

Dave

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Dec 3, 2009, 6:46:24 AM12/3/09
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It's a wireless one, the ESP Infinite (the following link is to the Infinite
PRIME but I've just got the bog-standard Infinite - and I'm using the
wireless external sounder with it)

http://www.tlc-direct.co.uk/Main_Index/Alarm_Index/Wireless_index/ESP_InfinitePrime/index.html

Thanks for your help.


Peter Parry

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Dec 3, 2009, 7:21:09 AM12/3/09
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On Thu, 3 Dec 2009 11:15:33 -0000, "Dave" <do...@bother.com> wrote:

>What happens to a burglar alarm (just a stand-alone one, not centrally
>monitored) when mains power is off for days? I know that the internal
>battery will obviously discharge but does it actually trigger the sounder at
>any point, or does it just die quietly?

When you disconnect the mains the sounder in the panel itself may
bleep at you until mains is restored, the external sounder should not
activate.

Your bell box requires a separate mains supply to the alarm box so may
do something else to indicate mains failure.

When the panel battery discharges the external sounder should go off.
It should stop after 20 minutes but may go off again later.

In any case when the external sounder battery is nearly discharged the
external sounder may sound of its own accord, this will usually occur
between midnight and 03:00 when the external temperature drops to its
lowest (hence causing the battery voltage to fall). It will sometimes
then sound (often with a continuous tone) until the battery is fully
discharged, usually only a relatively short time - 10 to 30 mins. The
behaviour of alarm sounders as the batteries discharge is rather
unpredictable

The only sure way of not annoying your neighbours is to disconnect
both the panel and bell box mains supplies and disconnect their
internal batteries.

Andy Champ

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Dec 3, 2009, 3:08:15 PM12/3/09
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Peter Parry wrote:
>
> The only sure way of not annoying your neighbours is to disconnect
> both the panel and bell box mains supplies and disconnect their
> internal batteries.
>

Wear ear plugs when disconnecting bell box internal batteries. It's not
nice if they go off 1 foot from your ear.

Andy

Peter Parry

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Dec 3, 2009, 5:08:42 PM12/3/09
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On Thu, 03 Dec 2009 20:08:15 +0000, Andy Champ <no....@nospam.invalid>
wrote:

>Wear ear plugs when disconnecting bell box internal batteries. It's not
>nice if they go off 1 foot from your ear.

Especially when you are 20ft up a wobbly ladder :-).

Dave

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Dec 4, 2009, 4:44:12 AM12/4/09
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Thanks everyone :o)


Message has been deleted

TheScullster

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Dec 4, 2009, 6:51:55 AM12/4/09
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"Dave" wrote

As others have said +
Do you have instructions for the alarm/bellbox?
My bellbox is an Odyssey model - this can be forced into "hold-off" mode by
testing the strobe 3 times in 30 seconds.
In hold-off mode, the box doesn't sound when the lid tamper circuit is
broken - handy for not blasting your ear drums up a ladder.

Phil


dennis@home

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Dec 4, 2009, 9:25:42 AM12/4/09
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"slider" <sli...@slide.com> wrote in message
news:hf877t$i9a$1...@adenine.netfront.net...


>
> "Dave" <do...@bother.com> wrote in message


8<

>
> Once power is disconnected, the alarm will activate. Your external bell
> box will most likely have a battery back up. The external box will sound
> until either battery goes flat, or power is restored and alarm reset.
> Best option is to enter the engineer code into the alarm (if you know it).
> This will stop the alarm sounding when power is disconnected.

Not on mine it won't.
There are many alarms around where doing that has zero effect on the bell
box.


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