In article ,
Martin Brown writes:
On 25/09/2017 14:56, Dave Plowman (News) wrote:
In article ,
Huge wrote:
If you do your own, don't connect up the external sounder until
you have managed at least 3 months with no false alarms.
Otherwise, you will have blown all credibility in your alarm
by your neighbours, by the time you have it working properly,
and then it's worthless.

While this is true, I'd argue that all unmonitored alarms are worthless,
other than to annoy your neighbours.

My self installed one phones my mobile via an SDI unit. Or anyone else I
programme it to dial to.

I have wired reed switches on all accessible doors and windows, and PIRs
covering pretty well everywhere. Nothing wireless. It has never given a
false alarm. But would add no pets, etc.

Mine is hardwired too. I think wireless has probably become more
reliable now. It had a terrible reputation when mine was installed.

Most false alarms are caused by sloppy installation.

We get the odd false alarm in mid summer from young bats getting in from
the loft. They can find the tinniest gaps and are warm blooded.

Spiders getting inside the PIR detectors is another. Their shadow might
be ambient temperature in the housing but if there is a sunny warm spot
in the room then that is sometimes enough to get a trigger.

I reckon spiders in the works is one of the most common false alarms.

The PIR detectors are designed to be insect-proof for this reason.
That does assume you drill the correct sized holes for screws and
cable.

Certain neighbours have particularly naff installations which always
trigger for a few seconds before they manage to reach the control panel.


--
Andrew Gabriel
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