I will do that (run the wires close to metal walls). I will also twist them. I suspect that just twisting them ought to be good enuf.
Um, the top box _is_ the place where I placed the solid state relay for the water cooler receptacle. But the receptacle is in the bottom box, as is the power source, so I cannot avoid running wires from and to there.
See
Receptacles
Chris, my IGBTs are already mounted on the OEM heatsink. Whatever equipment they were taken off of, they came with that heatsink. I figure that it should be good enough. The whole system of 4 IGBTs and the heatsink weigh, perhaps, 12 lbs. It should not be a big deal to evacuate about 1.2 kW of heat (worst case) from there.
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