I'm looking for a project box that plugs into a UK mains outlet and has a socket on the face to allow something else to plug into it.
A bit like this:
My plan is to mount a Shelly relay into it so that I can control an extractor via MQTT. The Shelly relay will then plug into a Zigbee outlet that is shut down every night when I've finished in the workshop.
The one taken apart above is a remote control plug and I thought I might be able to repurpose it and fit the relay into it, but it is too small and modifying it would remove the clips that hold it together.
Similarly I have a mechanical time plug that suffers from the same size limitation.
The relay is 38mm x 42mm:
I have searched amazon, AliExpress and google generally but am turning up absolutely nothing.
Any ideas?
Well, that could’ve gone better 😬
I've not seen such a plug with space enough for a Shelly. There are small junction boxes that will fit the Shelly, or you can 3d print your own. I've put mine in stout 3d printed (PETG 4mm thick) cases with cable glands for strain relief on the entry and exit cables, the lid secured with screws and strong fixing points for screwing the box to the wall.
But small junction boxes for electrical use are readily available of course. So would not a small junction box sitting very near your electric socket and plugged in with a short connection lead to the socket not suffice?
But I think you must be looking for a real neat and tidy solution. But as one who usually does my own electrical wiring I'm not aware of anything along the lines your describe. (and I know one should not DIY electrical stuff these days, but when I bought my first home in the 70's doing your own DIY was often the way so I still dabble, but I did get in an Electrician to feed some wires in my loft space, I didn't fancy crawling with the spiders up there 😎 )
If your workshop wiring and outlets are enclosed in trunking then you could just ensconce the shelly and electrical connections within the trunking. Of course then make sure the outlet cable to the extractor is suitably fixed with a few cable staples for strain relief.
I was really after a neat solution whereby the extractor plug plugs into the Shelly that is plugged into the outlet. The outlet being zigbee controlled.
I had thought of a separate box containing the Shelly that plugged into a mains outlet and may still take that approach if all else fails.
The original idea was to put the Shelly in the trunking, but I wanted the zigbee front end to it. I have ordered some zigbee controlled relays that could go before the Shelly in the trunking so that a specific outlet would be fed as a spur from the zigbee relay, then the Shelly relay and then to the outlet, and again that is still an option. It would look neat from the outside at least.
I wired the workshop myself and, like you, grew up with doing my own electrical work. Luckily I have a good neighbour that is an electrician. I wired the workshop and he did the final connection to the consumer unit in the house. He checked it all over and tested it and gave it a ticket.
I have a way to go with finalising the gate modules yet, so I have plenty of time. I'll keep looking
Well, that could’ve gone better 😬
I have finally found a solution for the mains in/out project box problem. I have searched for sacrificial products before having the right configuration, but none looked suitable. They were either the wrong shape or didn't look big enough to house the Shelly relay.
After another search yesterday, this turned up on Amazon - "https://www.amazon.co.uk/gp/product/B0CPT4SJVC"
They are under £5 and have enough room for a Shelly relay. In fact the internal construction is ideal for stripping out the guts and replacing with your own stuff.
This is the internals - There was another plug in PCB on top of this one, but in my enthusiasm, I forgot to photograph it first.
The installed relay looks quite neat, well, it would have if I'd done a better job.
And the finished item looks made for the job.
Well, that could’ve gone better 😬
A nice find when using shelly controlled mains plug. I had to have a quick peruse back on you project post to remind me of the context, and I see its to plug in a wall wart to provide the DC volts to your blastgate control electronics.
When you made your original post on this you were looking for some zigbee controlled sockets where you could also included a shelly. But reading your post I then got to wonder if shelly produces something directly and I came across the following product. Maybe this would also be an option?
This is to turn the extraction system on rather than to power the modules themselves.
It probably sounds a bit convoluted, but each blastgate module and the extractor are plugged into zigbee outlets, along with several other things. So in the case of the Shelly relay, the Shelly is controlled over wifi via mqtt, and is controlled by the gate modules publishing an extractor on command when the gate is half open.
The zigbee outlets are controlled by the Hubitat home automation hub. which switches all zigbee workshop outlets off at night. There are many things plugged in and I'm a bit fire conscious. (Read as paranoid) 😊
Thank you for the link, I don't think I saw the Shelly plug when I looked, but it isn't suitable for inductive loads.
Well, that could’ve gone better 😬