The common understanding is that in auto/RV simple 12V circuits the positive side is called hot and the negative side is called ground. I have been trying to understand this terminology and its origin.
I understand that in 12V systems that are grounded to earth the side that is not grounded is hot. The same reasoning applies in 120V systems, that is, the wire that is not grounded to earth is hot.
But in simple 12V systems that are not grounded to earth the same terminology seems to be used and the distinction appears arbitrary to me. As best as I can tell the negative side is called ground because it is typically run through the frame as sort of a giant buss while the positive side is run through only through wires. So in older positive ground cars the negative would be hot, right?
Is this logic correct or is there something I am missing?
This may be nitpicking but I am afraid I am missing something in my understanding of 12V systems.
Thanks for your help.
I understand that in 12V systems that are grounded to earth the side that is not grounded is hot. The same reasoning applies in 120V systems, that is, the wire that is not grounded to earth is hot.
But in simple 12V systems that are not grounded to earth the same terminology seems to be used and the distinction appears arbitrary to me. As best as I can tell the negative side is called ground because it is typically run through the frame as sort of a giant buss while the positive side is run through only through wires. So in older positive ground cars the negative would be hot, right?
Is this logic correct or is there something I am missing?
This may be nitpicking but I am afraid I am missing something in my understanding of 12V systems.
Thanks for your help.
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