Re: USB controlled mains switch

On 19/01/2025 09:04, Chris Green wrote:

Adrian <bulleid@ku.gro.lioff> wrote:

I'm looking for a USB controlled mains switch (230V AC) that I can
connect to a PI to turn a mains power supply on and off.
>
I've done a bit of digging around on the net, and the options seem to
fall into two categories, either a relay device which means having to
rewire the device (which I'd rather avoid), priced around 30Euros or one
that sits in line (between the device and the supply).  The latter
appears to be in excess of 100Euros, which is considerably more than I
want to pay.
>

I don't understand the difference. Surely anything that's going to
turn something on/off needs to be "one that sits in line (between the
device and the supply)" doesn't it?
 Do you mean (the ones that cost 100 Euros or more) something that
already has a mains plug and socket on it?  I think they're going to
be expensive simply because they aren't much in demand.  What 'the
world' wants is a WiFi connected switch and they're two a penny of
course.
 

Any suggestions on where to look ?  I'm not interested in a wireless
solution, as it is likely to be used in places where signals are not
reliable.
>

I think you'll probably have to bite the bullet and get a relay board
of some sort. Does it **have** to be USB?  There's lots of quite neat
relay hats for the Pi.
 

They aren't especially able to handle 230V at sane currents.
I made my own board up.  Featuring onboard PSU and mains chokes and filers and a fuse, a 13A capable relay and a pi PICO. Also has an optional temperature sensor hooked up to the ADC
Can send you the Gerbers if interested
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