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Simple electrical insulation question. Answered

If I have a 10AWG insulated solid copper wire and the THHN insulation is rated for 600V, should I worry about a 5000V 60ma current arcing straight through the insulation if its coiled in a helical form?


If its a multilayer coil, forget it. If its a single layer, and there are enough turns to spread 5kV over more than 10mm or so, it may work. The actual turn-to-turn voltage is pretty low.

Say the coil height is roughly 6 inches (single layer). With the wire length totaling to about 4 or 5 feet. Would 5kv be enough to break the insulation down over time as framistan says? Also, how many watts can that much wire handle? Is 300 max?

5kv times 60mA equals 300 watts! Thats a lot of watts. If it starts to arc over, it will cause a fire. Even if it seems to be working, it may break down over a time period of several days or weeks and then arc-over suddenly when you are not home or not watching it and start a fire. I think it would not be wise to place such a high voltage onto wires rated much lower. If its just a quick test as an experiment, then maybe it would be ok. I don't think coiling it would make any difference. Also, this kind of voltage and amperage could be lethal if someone gets shocked. It doesn't have to "fry" you... it just has to stop your heart. So be carefull.

I think so - The 600 v is an important figure - called the breakdown voltage.