WiFi relay

I’m after a WiFi relay that simply breaks and completes a circuit. I.e isn’t a switched live or similar. Any one have any experience/recommendations.

Shelly 1

I use a SONOFF basic switch for my wifi switching relay needs. about £5 – £7 on ebay

Runs off the eWeLink App

240v though

Thanks. It’s not so much the input voltage as simply controlling a switch so the mains or other power is isolated from the switch. Shelly looks like it could be the job.

@muddyjames getting into home automation in a big way and after doing LOADS of research settled on Shelly as the best solution. Really impressed with the ones I’ve used thus far so ordered another few hundred quids worth in their BF sale 🤣 It’s an EU company & you can buy them direct from the manufacturer which I’m more confident about than some unknown quantity off eBay etc. They are also very quick to respond on FB if you need any help or advice.

Biggest plus (for me) is they work out of the box via MQTT or their REST API if you’re running a Home Assistant or Node Red server which means you can control them locally without having to go via a cloud service.

The Sh1 can run off 110-240v or 12v or 20-30v DC so really flexible, and the relay can be isolated e.g. the Shelly can be powered off 240v but can be controlling a 12v DC device.

Just make sure you use solid core cable or stranded with a properly crimped ferrule as that’s what their terminals are designed for… seen a few cases of burnt-out units on their FB page but most if not all can be put down to poor installation.

A mate of mine who Knows Things recommended Shelly units as a means of getting around the ‘no neutral’ quandary when creating smart light switches.

Dunno if that’s applicable to the OP though, I don’t understand the question.

doesn’t sound like it, but you’d need a particular Shelly for no-neutral (either Shelly 1L or Dimmer2) and they DON’T have independent circuits for the relay i.e. if you power it with 240v the relay will switch 240v also. That said they are perfect for retro-fitting to standard light switches in UK no-neutral setups!

👍 Aye, Dimmer2 is what my mate bought. I find their range confusing TBH, they need an overview page.

Cheers all. I have an external boiler that has a jumper wire that connects two terminals together. When the jumper is in place boiler on, when it is removed boiler on standby (not off). There’s a low current through the wire. I’d like to put a WiFi switch on the wire to remotely control the boiler. But all I need is a switch, no power. Hence the need for a true relay.

I find their range confusing TBH, they need an overview page.

that has been mentioned a few times on the FB page! Although, given that photos of dangerous wiring jobs are also pretty common when people ask for help, there’s maybe an argument against making the range more accessible tbh!!

@muddyjames yes Shelly1 will work for that (obviously you’ll still need to power the Shelly itself, via 240v or whatever)

Cool thanks zilog- yes realise the relay and WiFi gubbins will need to have some power itself. I was wondering about using a USB supply but 240 maybe easiest.

the relay needs a minimum 12v DC to work so a USB supply won’t cut it. You can of course power it from a 12v supply plugged into the mains (you need to change a jumper on the Shelly if so but that’s all pretty clear in the manual) which might be preferable if you aren’t going to be putting it in some kind of junction box or enclosure.

To complicate the scenario is there a temperature probe that I can use such that I can set a temperature to trigger the relay?

And further complicate, can I interlock another Shelly in such a way that it is on for 15 mins (say) after the other goes off

@muddyjames there’s an add-on temperature sensor for the Sh1 that you can connect up to 3 thermistor probes to.

Yes you can get Shellys to interact with each other… depends exactly what you want to do… there’s some limited functionality (including a timer) with them communicating directly via HTTP, otherwise anything you can think of can be accomplished via an external service – either a server you host yourself e.g. Node Red (which is what I use) or a cloud service such as IFTTT or possibly Shelly’s own cloud service (never used either personally).

The Shellys don’t communicate directly via RF or anything, so just be aware that although each Shelly will operate independently without WiFi, any communicate relies on your WiFi network being up.

I can really recommend the Shelly Support FB group, you’ll get an answer on anything technical very quickly either from other helpful users or direct from staff who monitor it.

Zilog – brilliant thank you very much.