CT controlled relay

[Gareth J]

Does a simple widget exist that lets me monitor the current through a wire (ideally a CT clamp but could be wired in) and close/open a relay based on what current is flowing?

I want to monitor the supply of the second solar diverter (iboost) and, if its drawing more than the rating of my appliance (currently a 300W dehumidifier), close a relay and let me run it. Obviously that would then drop the available power down by the appliance rating, so, in an ideal world the widget would know this and now look for *any* demand at all through the iboost. But if a simple "on if over xW threshold" widget existed, that'd be fine too - I'd run it through a timer relay to let it run for 10mins if the condition was met or something like that.

[Oldgreybeard]

Sounds like a job for a current sensing relay. One of these can sense a current and switch a contactor at a set level, so should be OK for what you're after I think. Something like this, perhaps (loads more around): https://uk.farnell.com/carlo-gavazzi/di ... dp/1824777

Or this one if you want a built-in time delay capability: https://uk.farnell.com/broyce-control/l ... dp/2677811

[Oldgreybeard]

Just found a cheaper option from China that may do the job: https://www.ebay.co.uk/itm/203964987912 ... SwwHNer~gI

[Gareth J]

Nice suggestions, thanks. They look pretty much ideal.

Was also looking at a "Shelly" which looks like a really useful gadget and works wirelessly, which would give a bit of flexibility