Burglar alarms

[Huge]

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

[Andy Burns]

I think the default position here is that alarms don't have any credibility, just listening to the widespread cacophony whenever we have a power blip says everything about how well maintained they are.

I certainly don't bother looking when they go off, unless it's a repeat nuisance, then I might wander out in my dressing gown to be sure I know who to complain to.

[Bob Eager]

We have double gates at the side of the house (open into a side street). Not sure if they came in that way (easier via neighbours on the other side). They lifted both drop bolts, and defeated the two cross bolts (locked) by pushing both gates open at once. Can fix that by installing

450mm bolts that cross both gates; they would make too much noise defeating those.

Sheds were broken into by destroying doors. Wireless alarms going on those.

Floodlight wiring is there but I never got a tuit before. They are going in now.

[Tim Lamb]

In message , Andrew Gabriel writes

Sound advice:-)

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[Dave Plowman (News)]

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.

Most false alarms are caused by sloppy installation.

[Andy Burns]

With some of the alarm receiving centre based ones, operators at the centre can remotely connect to cameras within the PIRs once triggered, and presumably that is sufficient level of "intruders on premises" to interest plod?

[F]

Not where I've put ours...

[Steve Walker]

Not at all. If the alarm next door goes off, I'll investigate, but if the one across the road does, I'll ignore it - the difference is that the former almost never goes off, while the one over the road frequently does. Similarly, I would hope that if ours went off, a neighbour would take a look, as it never normally does.

SteveW

[Steve Walker]

A relative has a floor safe. As the house (other than kitchen and bathroom) are fully carpetted, no burglar is going to spend the time to search properly for one.

SteveW

[Peter Parry]

Only if it a registered Type A alarm. For Type B alarms the ARC are not permitted to contact the police upon alarm activation.

About 95% of all alerts from Type B alarms are false alarms.

[Dave Plowman (News)]

Sigh. If you go off on holiday, you change it to phone the key holder. Assuming you have a relative or friend you trust enough to be one.

[Martin Brown]

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

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.

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

[Huge]

Mine is a recent wireless system. We've had it about 18 months and the only false alarms have been user error or bats in the garage.

The alarm man who came to check out said the bat problem is worst in the autumn, caused by them looking for somewhere to hibernate.

One advantage of wireless PIRs; no holes in the casing to let the wires out and the spiders in.

[Dave Plowman (News)]

Some BluTack over the cable etc entry? Although never had this problem although plenty spiders here.

[alan_m]

Or a lack of maintenance. The backup battery in an alarm control box is not fit and forget. The backup battery is trickle charged when mains is present and intended to provide power when the mains drops out. After a few years the battery cannot provide the instantaneous power to maintain the control box when the mains fails, even for short glitches, and hence the alarm is triggered. This can be easily tested by just turning of the mains to the alarm at the consumer unit. A new battery every 2 couple of years stops false alarms caused by this.

I attach a label (brother tape) to the outside of my alarm control box giving the date when the battery was changed - and the type number of the battery. It sometimes surprises me when checking how long ago the battery was fitted.

[jrwalliker]

Unless they bring a metal detector, which is apparently quite common in some areas where gold is often kept at home.

John

[charles]

I understand taht the BS for this requires battery replacement every 5 years at a minimum,

[The Natural Philosopher]

In the same way that most car crashes are caused by bad driving?

[Andrew Gabriel]

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.

[Dave Plowman (News)]

I'd expect a quality SLA to last rather more than 2 years when run in a float mode.

Don't have many mains glitches round here - or rather ones long enough to upset things like clocks that don't have a backup battery, or to be otherwise noticeable.