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Old 03-30-2020, 09:53 AM
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Quote:
Originally Posted by patrickt View Post
Or run a parallel wire with the ammeter circuit. I have a 12 gauge parallel wire with my ammeter circuit and it does two things: 1) It mutes the heavy draws of current when my fans come on, that used to send the needle all the way over to the left where it would get stuck, and 2) it dynamically re-routes current around the ammeter (which I really like) should the ammeter start to overheat. The ammeter still registers correctly, the readings are simply reduced. They don't, of course, reduce past the zero mark and give you an incorrect direction of current. But, it pretty much eliminates the possibility of the ammeter overheating because, as the ammeter heats up because of a failure, it creates additional resistance in that leg of the circuit and current will then just go down the parallel path (that's just Ohm's Law). Think of it like having two parallel wires, of equal gauge, running to a 120 watt light bulb, which will draw roughly ten amps. All things being equal, each wire would have five amps on it. On one of those two wires you have a 20 amp fuse, and on the other wire you have a one amp fuse. You will not blow the one amp fuse because, as the filament heats up, the resistance increases and the current then passes through the other wire.
For those of us that don't know electrics as well as we should; could you explain a bit more granualarly how to run a parallel wire?
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