Loss of supply alarm

[yellowvanman]

Customer feeds an outhouse via a RCD fused spur. Tripped a couple of times in the last 6 months and because there is a freezer out there potential to not know supply has tripped and lose all thats in the freezer.

Anybody had cause to use some sort of alarm in the event of the RCD tripping.

Was thinking about using an emergency light, but that'll only work for 3 hours and relies on somebody going into the room where the supply is. Could rig up something with a relay and a buzzer, but why re-invent the wheel when somebody has done it already.

Ideas gratefully received!

 

[tazz]

Security or fire alarm psu with battery backup......simply relay & buzzer, if power fails buzzer sounds. A simple 1 amp psu with 7 a/h battery will give a 30mA sounder over 200 hours of operation

 

[yellowvanman]

Security or fire alarm psu with battery backup......simply relay & buzzer, if power fails buzzer sounds. A simple 1 amp psu with 7 a/h battery will give a 30mA sounder over 200 hours of operation

Thanks, but was thinking don't really need a battery (which is relatively large) as I have a permanent supply supplying the RCD spur!

My thinking was to have the RCD'd supply energising a relay, if supply lost, relay changes over and permenant supply powers a sounder!

 

[tazz]

Same principle, but a cheap psu gives you the lower voltage for sounder and the benefit of sounding if all power is lost

 

[Martin Kerr]

If the installation had an intruder alarm with a spare zone , you could install a relay ,normally energised from the load side of the RCD fused spur and allocate the alarm input to a 24 hr zone.

 

[yellowvanman]

Same principle, but a cheap psu gives you the lower voltage for sounder and the benefit of sounding if all power is lost

Where can I get a cheap psu?

 

[yellowvanman]

If the installation had an intruder alarm with a spare zone , you could install a relay ,normally energised from the load side of the RCD fused spur and allocate the alarm input to a 24 hr zone.

No Alarm in house!:nonod:

 

[Martin Kerr]

Where can I get a cheap psu?

I wound not think the price of a power supply would be an issue , if you lost the contents of a freezer a couple of times?

 

[Deleted member 72666]

I've seen baby mains powered monitoring units sound off when the transmitter loses supply, the receiver makes a loud 'white noise' sort of sound, maybe that setup could work temporarily until a more professional solution be found.

 

[snowhead]

Would it not be wise to investigate why the RCD is tripping?

It's probably the freezer that's causing it.

 

[DPG]

Would it not be wise to investigate why the RCD is tripping?

It's probably the freezer that's causing it.

Best answer yet by far. Daz

 

[Richard Burns]

Have a search for main power failure alarm plugs a lot of the systems will provide texts to phones, some of them provide local alarms, generally cost over £100 this basic one is £68 or they are available with EU plugs from china for about £20, save any messing about wiring stuff up, who would want to do that!!

 

[Octopus]

If the supply is using SWA cable and the cabling in the shed is surface, I would remove the plug from the freezer and wire it using a FCU. If they need another socket in the shed then fit an RCD socket

 

[telectrix]

If the supply is using SWA cable and the cabling in the shed is surface, I would remove the plug from the freezer and wire it using a FCU. If they need another socket in the shed then fit an RCD socket

or label the socket outlet as dedicated to freezer.

 

[Octopus]

or label the socket outlet as dedicated to freezer.

OK - your solution is a bit cheaper!

 

[DPG]

I wouldn't hardwire it to an fcu. Makes it expensive when the fridge fails and they need to get a sparky in to disconnect it and reconnect the new one. Daz

 

[UNG]

You could use an RCD with an auxiliary contact which operates an alarm when tripped

Or if the freezer has an auto defrost function check the heater element is not on it's way out seen this cause problems many times in the past

 

[Octopus]

I wouldn't hardwire it to an fcu. Makes it expensive when the fridge fails and they need to get a sparky in to disconnect it and reconnect the new one. Daz

Really? How often does a fridge/freezer fail? Sounds like they have lost a couple of full freezer loads full already!

 

[DPG]

At some point the fridge will need replacing. Then they will need to get a sparky in to disconnect/re-connect. Better on a plug top. Daz

 

[fall-apart-dave]

It's easy, you just stick a relay like this: Schrack PT270T30 230V Relay With LED FD5C9 | eBay after the RCD, connect the normally open when energised side to this: https://www.tlc-direct.co.uk/Produc...owC6NhCe55twXc74aBtg-C9J3If9cm8JnyBoCd8rw_wcB , and feed mains to the input of that relay from before the RCD. RCD trips, contacts close, mains from before the RCD directed to the alarm. They will sharp know about it!!

Ok, maybe the bell is overkill, but you get my point. It's cheap and easy to do.