(Note to all the normal people in the forum-- this kind of stuff gets me unreasonably excited; I know it's odd, but at least it's not immoral!!) Just to be argumentative, what kind of power loss would a 0.4 Ohm snubber resistor cause in a normal charging circuit? Seems like cheap insurance to me.
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Doesn't it seem odd to anyone else that we have the NEC for house wiring, but (evidently) nothing like that for vehicles? Not to directly knock anyone, but the egregious wiring I have witnessed, e.g. failed tapcons in the ceiling of my 2001 Hawk, make me think a little bureaucracy in RV wiring might be a good thing...
I think the RV Industry Association (RVIA) sets standards of some kind, but dunno how much force they have. One problem that I see is the conflict in color codes between commercial/residential and automotive/marine wiring.
Hmm, E=IR? (Been a looong time and I wasn't real good then...)
http://www.the12volt.com/ohm/ohmslaw.asp
Lessee, 12V / .4 Ohm = 30Amps possible through the resistor, but looking at it another way, there's a very large voltage drop across the resistor at high current, so nothing would be happening? At a 10Amp flow, the drop would be 4V; at a 2Amp flow, the drop would be 0.8V and that would be enough to terminate the charging process way too early.
I recall that a small (Ohm-wise) ballast resistor in an ignition system drops the voltage to the coil from 12VDC to 6VDC during starting and that ceramic resistor gets very hot in the process.
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Doesn't it seem odd to anyone else that we have the NEC for house wiring, but (evidently) nothing like that for vehicles? Not to directly knock anyone, but the egregious wiring I have witnessed, e.g. failed tapcons in the ceiling of my 2001 Hawk, make me think a little bureaucracy in RV wiring might be a good thing...
I think the RV Industry Association (RVIA) sets standards of some kind, but dunno how much force they have. One problem that I see is the conflict in color codes between commercial/residential and automotive/marine wiring.
Hmm, E=IR? (Been a looong time and I wasn't real good then...)
http://www.the12volt.com/ohm/ohmslaw.asp
Lessee, 12V / .4 Ohm = 30Amps possible through the resistor, but looking at it another way, there's a very large voltage drop across the resistor at high current, so nothing would be happening? At a 10Amp flow, the drop would be 4V; at a 2Amp flow, the drop would be 0.8V and that would be enough to terminate the charging process way too early.
I recall that a small (Ohm-wise) ballast resistor in an ignition system drops the voltage to the coil from 12VDC to 6VDC during starting and that ceramic resistor gets very hot in the process.