On 15/05/2011 11:55, Dave Plowman (News) wrote:


I'd point out the likely problems with wireless sensors (battery costs and
the need for regular replacements) to the owner and let him decide.


I have a wireless system.
The magnetic sensors take two CR2023 cells (around 10p each if you by in
bulk from eBay) and PIR's take one PP3 (about 70p).

In both types of sensor the batteries last over 2 years. They signal the
control unit when the battery gets low so you get an alert message.

The siren uses solar-charged lead/acid cells, so my running cost for 5
mag sensors + 5 PIRs is under £4 a year. That would rise if you wanted
mag sensors on every window.
It was an absolute doddle to install, and being wireless it's easy to
protect the shed and a detached garage too.

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