Wiring a relay?...................

[HappyHippyDad]

Hello all..

I have been asked to wire a relay into a FCU for a 3kW immersion.

The plan is for the customer to be able to access the immersion over WIFI.

The relay is a Shelly 1pm WIFI relay, 16A 110V - 240V.

I have not wired a relay before, hence asking on here.

The wiring diagrams on the MI (see pic) show it being used for a light, which will include a light switch. Therefore do I just make a link between the L and SW as seen in my written diagram? Do I need the link, or are these terminals purely so the light could still be used from the switch?

I don't see how I can wire this directly into the FCU for the immersion as the relay has a common neutral, I would therefore loose the double pole function of the FCU. So, I'm assuming the relay would get wired into the load cable coming from the FCU going to the immersion?

Thanks in advance.

 

[Lucien Nunes]

The WiFi relay is rated at 16A, but it will be designed for compactness and a 16A load would probably be pushing the actual relay within towards its limit. I would be interested to know how well they last when operating a 3kW immersion. Might be 100% fine and the electronics might be life expired long before the relay itself. But things burn out with immersion loads that in theory ought to survive, and many peoples' experience of this product will be switching trivial lighting loads etc. In a critical application I would probably go for belt and braces and use it to control a contactor or power relay.

 

[Avo Mk8]

I've had the Timeguard wifi switch operating the main (3kW) immersion in a holiday cottage for about 3 years now, and all good. The app is a bit clunky, but has a log of the past 24hrs showing when the load is active (not just the time it's set for - it indicates when current is being drawn), thus showing when the water has reached set temp, so can be reassuring!

WiFi Controlled 16A 7 Day Programmable Timeswitch | Timeguard (NTTWIFI)

 

[HappyHippyDad]

The relay worked as expected. A link was needed between L and L1.
Only problem was the neutral terminal screw didn't tighten up, so he is returning it. Still, glad I know how to do it now.
Thanks again for all the help.