Re: Circuit protector

Posted by HH56 On 2018/7/13 22:49:24

I believe that bypass or protector is essentially a length of nichrome resistance heater wire. If the fuse is good and in place the fuse shorts across the wire effectively bypassing it because there is no resistance in the fuse as compared to the wire. Current always flows thru the path of least resistance so none goes thru the wire as long as the fuse is good. If the fuse blows, that is a big open and lots of resistance so current then starts flowing thru the wire. Just like in a heater, the wire gets red hot as it passes a limited amount of current depending on the specs of the wire. Because of the resistance, the voltage will be lower but will be enough for a few lights albeit at a dim level. If the load gets too high such as a solid short the heater wire will eventually be unable to carry the current. Best case will make bulbs too dim for any use or worst case, wire will burn open. I think I recall one of the regular posters a few years ago needing to replace one which had burned open and asking about a source and specs for the wire.