Sonoff wifi switches with no earth pass-through, are they safe?

[jgc1457]

Hi all,

I'm new here and want to say thank you in anticipation for the advice you can give me -- I hope it's okay to dive on to this forum as a total newbie with a question rather than just an introduction, but I'd really appreciate some insights!

I bought a Sonoff wifi switch for about £8 from Amazon; I've fitted it to a modern table lamp, and it works very well. I'm thinking of buying some more, but I have several lamps which are made from old ceramic vases with a brass bayonet bulb holder at the top, all of which have 3 core cables to their plugs.

The Sonoff switch only has L and N connectors, no earth connector, and I can't see a neat way of connecting the earth from the lamp to the plug without using terminal blocks inside their own protective box or some other such Heath-Robinson setup.

My house has those circuit breakers in the consumer unit (RCDs?) but I don't know if they are a sufficient protection if I fitted these lamps with Sonoff switches and ignored the earth.

My gut feeling tells me that ignoring any safety device is done at one's peril but these switches are really convenient and easy to use so I'm hoping the answer will be positive!

Thanks in advance,
Jodi.

 

[Wilko]

Hi Jodi and Welcome to the Forum!
Yes, you definitely need to carry the earth through to the lamps. Looking at the advert I can't see type approvals for UK use on the enclosure, which may be another concern.

 

[jgc1457]

Hi Wilko, thanks for the speedy reply and the welcome! Is there a better way of carrying the earth through that I haven't thought of? (My idea is pretty clunky and wouldn't look very attractive, involving terminal blocks and chocboxes...) Thanks!

 

[westward10]

Agree you must maintain the earth, can you show a pic of it.

 

[jgc1457]

Hi Westward, this is a pic I've just found (not my own pic as I'm at work at the moment). You can just see the two small terminals for the live and neutral, and there is an identical pair of terminals on the other side of the unit for the output. No provision for an earth cable, so I'd have to run that outside of the unit in as neat a way as I can muster...

 

[westward10]

Yes that doesn't provide a facility to connect the earth and running around the outside of it isn't the best solution. The only option I see is to replace the brass lampholder with an all insulated one (plastic) and rewire using two core cable. I suspect your lamps have a metal tube to which the existing lamp holder fits to which wouldn't need an earth providing as long as none of the conductor insulation (the brown and blue wires) is exposed to this tube and they are contained within the lamp holder.

 

[jgc1457]

Ah, that sounds like a much better idea than mine, thanks Westward10 -- a bit more effort but then at least I know it's a 'proper' job rather than a bit of a bodge. Thanks for the suggestion, greatly appreciated

 

[Gavin John Hyde]

John ward did a good youtube video on these switches. Quite an interesting watch. Seemed to hold up quite well.

 

[jgc1457]

Thanks Gavin, an interesting video even though I didn't understand 90% of it! I always find it fascinating when someone can just look at a circuit board and tell you exactly what each component is for and why it's there though -- it seems quite reassuring that the thing isn't going to catch fire but I just wish they'd included an earth pass-through; it seems like such a simple omission. His other videos (especially where he puts a kettle through one of them) are good too so thanks for pointing me in his direction.