Re: Lightning Strike and surge

david <none@xxxxxxxxxx> wrote:

The only thing a surge protector can possibly do is shunt surge
current away from the item being protected. The MOV is a variable
resistor that had a low resistance when the surge voltage rises
above its turn on threshold.

I thought so too, until after reading many intelligent counter
replies to w_tom. When a very large voltage appears at the MOV
input, the MOV short-circuits thereby making both points the same
voltage. I suppose the current flow might be extreme, but shunting
electricity is not really what protects the circuit. Since the
circuit input and output voltages are the same thanks to the MOV
becoming a short-circuit, destructive current flow through the
protected device is (ideally) prevented.

Good luck arguing with w_tom.




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