Alarm bells

DavidB

Western Thunderer
A couple of nights ago we had nocturnal felons and although they didn't take anything of ours (they did that 10 years ago), they did remove tools from a neighbour and went in to other places, cutting padlocks off. Buggers even borrowed the neighbour's wheelbarrow to cart the stuff over the fields up to a farm track. They kindly left the barrow.

I have an alarm in my workshop which is battery powered but not very effective (read: loud). I really want something mains powered and LOUD. Does anyone who knows about these things suggest something suitable? I shall add window alarms as well as a motion sensor.
 

Osgood

Western Thunderer
Plenty of choice - search for mains or 240v alarm siren.
I can’t make a specific recommendation but suggest you‘ll also need a mains relay (latching type so it will take a momentary signal from whatever low voltage sensor are using and then remain on) and a timer module so you can set the duration of the siren before it resets.

The mains sirens are an order of magnitude louder than standard battery types supplied with domestic alarm systems.
You might want to invest in a very basic mains powered domestic alarm system with battery backup and whatever sensors you require - the alarm panel should have an output suitable to trigger a latching relay.
 

markjj

Western Thunderer
A couple of nights ago we had nocturnal felons and although they didn't take anything of ours (they did that 10 years ago), they did remove tools from a neighbour and went in to other places, cutting padlocks off. Buggers even borrowed the neighbour's wheelbarrow to cart the stuff over the fields up to a farm track. They kindly left the barrow.

I have an alarm in my workshop which is battery powered but not very effective (read: loud). I really want something mains powered and LOUD. Does anyone who knows about these things suggest something suitable? I shall add window alarms as well as a motion sensor.
I would suggest something which has flashing strobe lights to. Many alarm systems have additional relay outputs that let you attach things to them.
 

Osgood

Western Thunderer
If you’d only asked 3 weeks ago you could have had one of these that I once tried on our business alarm system.
Installed during the Cold War, many were repurposed (and are still in use) as flood defence sirens.
A right so-and-so to power up as it was a 1 phase example (many were 3) and drew over 100A on startup, so required a fancy soft start unit (limiting current to 30A).
It only sirened once - upon testing once installed and interfaced with the alarm system, it took 30 seconds to get up to full pitch but from my vantage point 1km distant I concluded it would wake up half of the adjacent city, so it had to be downsized!
After 20 years in storage, last month it found a home in a Cold War museum.
36CAC27C-524E-41BE-8B04-457EE118CD76.jpeg
 

Osgood

Western Thunderer
Just the V8 without a silencer (it even has a nice strobe flame effect out of the manifold) would do the job for David!
 

Osgood

Western Thunderer
For us .co.uks I'm not so sure, I knew a chap who ran a scrapyard and who - despite warning signs - got into hot water with the Hot Fuzz over those.
 
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