02-13-2013, 07:18 AM
Steve,
Newell could have done many things better electrically in my coach than they did, but this is not one of them. It makes no difference what-so-ever which polarity of a circuit is fused. When there is just one positive cable, and one negative cable for a particular circuit, all the current that goes through one goes through the other. Breaking the circuit ( what a fuse does ) at any point stops all current flow. Often on a vehicle where the structure of the vehicle is used as a current carrying conductor ( ground is what it is normally called ) there well be multiple positive cables leaving a power source, and maybe only one negative cable from the body of the vehicle to the negative of the battery. Especially in those cases you can achieve circuit protection with just a single fuse on the negative instead of multiple fuses on the positives. I imagine that is what Newell did in this case. On my coach they fused some circuits from the starting and chassis batteries, and did not fuse others. Mine are ALL fused now. Failure of the insulation on any big positive cable leaving a starting or chassis battery and coming in contact with ground is going to produce one huge fault and I do not want to deal with. Should I ever have insulation failure my fuses will clear with no fuss or muss.
There is one other consideration worth mentioning. The negative cables from our batteries are basically at the same potential ( voltage ) as the surrounding steel and aluminum of the body of the coach. The addition of the fuse may result in extending an exposed connection closer to the body of the coach. It is just much safe to be working on an open connection that is negative and will not cause a huge fault should your wrench slip and come in contact with the body of the coach. That is why you ALWAYS disconnect the negative first when working on any negative grounded battery system.
Just remember before installing that spare fuse you wisely suggest to carry, there is probably some underlying reason the original one is open. Make every effort to understand the cause of the original failure before installing another fuse. Russ
Newell could have done many things better electrically in my coach than they did, but this is not one of them. It makes no difference what-so-ever which polarity of a circuit is fused. When there is just one positive cable, and one negative cable for a particular circuit, all the current that goes through one goes through the other. Breaking the circuit ( what a fuse does ) at any point stops all current flow. Often on a vehicle where the structure of the vehicle is used as a current carrying conductor ( ground is what it is normally called ) there well be multiple positive cables leaving a power source, and maybe only one negative cable from the body of the vehicle to the negative of the battery. Especially in those cases you can achieve circuit protection with just a single fuse on the negative instead of multiple fuses on the positives. I imagine that is what Newell did in this case. On my coach they fused some circuits from the starting and chassis batteries, and did not fuse others. Mine are ALL fused now. Failure of the insulation on any big positive cable leaving a starting or chassis battery and coming in contact with ground is going to produce one huge fault and I do not want to deal with. Should I ever have insulation failure my fuses will clear with no fuss or muss.
There is one other consideration worth mentioning. The negative cables from our batteries are basically at the same potential ( voltage ) as the surrounding steel and aluminum of the body of the coach. The addition of the fuse may result in extending an exposed connection closer to the body of the coach. It is just much safe to be working on an open connection that is negative and will not cause a huge fault should your wrench slip and come in contact with the body of the coach. That is why you ALWAYS disconnect the negative first when working on any negative grounded battery system.
Just remember before installing that spare fuse you wisely suggest to carry, there is probably some underlying reason the original one is open. Make every effort to understand the cause of the original failure before installing another fuse. Russ
Russ White
2016 Winnebago Vista LX 30T
#530 ( Sold )
1999 45' Double Slide - Factory upgrade 2004