I was wondering if there was a way to control an ikea dioder using it's own powersupply but turn on and off with an arduino digital pin?
I have not seen what you are talking about, but what voltages and current are we talking about, sounds like a job for a solid state relay
The ikea diode is highly proprietary, and only ikea knows how to control it.
You can call ikea HQ for that but it is not going to be cheap.
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