Dave Ett wrote:A protection system is easy, it's called a fuse! Better still a circuit breaker, so when the thing draws too much current the circuit breaker pops and you know it's time to de-coke...
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In most cases a simple fuse is not enough to protect semiconductors, as a fuse is very slow, depending on how high the current is, and very unprecise and a semiconductor burns out very fast.
At double the nominal current it can be many seconds up to minutes before it breaks. (10% over = 100hours! 200% 0,15-20seconds)
There are special semiconductor fuses, that are faster, but normally you would build either an electronic circuit to blow the fuse or to clamp the voltage/current

http://www.littelfuse.com/data/en/Data_Sheets/FKS80V.pdf
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Poul
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