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I want a battery powered (say 9v PP3), standalone, timer controlled relay that can close a 24v circuit.
It would be great to have the ability to program the timer with a number of programs as well as a boost
I guess the alternative is something that runs from the Mains:
http://www.ebay.co.uk/itm/180857386690
Ive got an immersion heater timer but its not a relay. I guess I could just add a 240v relay to it? Just need to stick it in a surface mounted box I guess?
Any basic timer unit can be converted to switch mains via a Relay, just make sure the relay includes a diode across the low voltage contacts to stop reverse EMF stuffing up the controller (most have the diode integrated).
What about something like this:
http://www.quasarelectronics.co.uk/ci0052-weekly-programmable-timer-relay-module.htm
£87.46
comedian, footflaps! 😉
Got a link (ebay?) to a suitable relay for me ff? Can I expect the diode to be inside one?
[url= http://www.maplin.co.uk/5a-miniature-relay-37515 ]Maplin p/n N13AW[/url] relay (DPDT, 240v coil). I guess that it would be the 8 pin base that you'd need.
Use that along with your timer that you already have - you should really enclose it so that you've not got the 240v terms exposed.
No snubbing diode req across the coil as its an AC coil - a snubbing diode would act as a half wave rectifier (ish) and probably stop the relay picking reliably.
thanks mrjmt. I think that's the cheapest way forward.
Yep, Id get a surface box for it.
Ive done similar with a two relay underfloorheating control.
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Sounds like the perfect excuse to buy an Arduino.
Many times Ive thought arduino or raspberry pi (thanks to Make mag & boing-boing), but who am I kidding. I have trouble with Microsoft Word let alone trying to learn to program something 😳
comedian, footflaps!
Didn't notice the price! That is a little steep....
BTW mrjmt, although I only need SPST I think, I assume that I might as well get a DPDT as they are more easily available and can be used just the same?
aye, just use one set of contacts. it just means you can isolate pos and neg if you really fancy it!
Intersting installation, using both copper and composite.