flattracker
Senior Member
Hopefully the final answer about ground
An answer as to why some think that folks confuse ground and chassis on motor vehicles is because the industry uses the term ground and schematics of motor vehicles utilize the schematic symbol for ground. Terms like negative ground and positive ground are prevalent. The English were fond of positive ground. I still will wire my bus like a house, meaning neutral will still have a wire, ground (green wire) will have a wire. Of course my electrical panel will be electrically connected to the chassis of the bus through the unistrut I am using to frame the walls. This means that through the electrical panel both neutral and ground (green wire) connect through the shell of the electrical panel. As my bus has a second alternator mounted on the engine that due to its mounting current flow originates from its housing, through the engine block, through a "grounding strap" to the frame of the bus. Thus the DC current flow will pass through the frame to batteries through their negative terminal, and through any device that will conduct electron flow to the positive of batteries that have a negative connection to the chassis. The current flow also returns to the positive terminal of the second alternator. The same operation of current flow occurs with the original Crown bus electrical system, but this electrical system is isolated from the RV electrical system. DC current will flow through the chassis for both RV and bus electrical, but both are still separate, since NO point of RV and Bus electrical have a common positive. Under normal conditions NO AC current will flow through the chassis of the bus. If you for sake of discussion had a power tool that developed a short between the HOT ac wire to the metal enclosure, current will flow to the ground wire (the third round pin of its plug) and cause the circuit breaker to trip. If any one is still confused, try an internet search for wiring of say a 1990 ford f250 wiring diagram. keep looking and you will find a schematic with a ground symbol. The term schematic is a term for a wiring diagram of an electrical or electronic device, such as a tv, radio, phone, etc. An internet search of "transistor radio schematic" should produce the following image:
In that image at the bottom wire is the symbol for ground. A lot of wiring diagrams for motor vehicles have that symbol. To me it is simple. AC ground is a green or bare wire connected in all circuits and in your electrical panel. In DC it is usually the chassis of the vehicle. Not all vehicles have a frame, but all have a chassis. AC ground only conducts with electrical failure (short to enclosure), DC in most vehicles ground /chassis carries current. Don't mix the two and you will be OK.
An answer as to why some think that folks confuse ground and chassis on motor vehicles is because the industry uses the term ground and schematics of motor vehicles utilize the schematic symbol for ground. Terms like negative ground and positive ground are prevalent. The English were fond of positive ground. I still will wire my bus like a house, meaning neutral will still have a wire, ground (green wire) will have a wire. Of course my electrical panel will be electrically connected to the chassis of the bus through the unistrut I am using to frame the walls. This means that through the electrical panel both neutral and ground (green wire) connect through the shell of the electrical panel. As my bus has a second alternator mounted on the engine that due to its mounting current flow originates from its housing, through the engine block, through a "grounding strap" to the frame of the bus. Thus the DC current flow will pass through the frame to batteries through their negative terminal, and through any device that will conduct electron flow to the positive of batteries that have a negative connection to the chassis. The current flow also returns to the positive terminal of the second alternator. The same operation of current flow occurs with the original Crown bus electrical system, but this electrical system is isolated from the RV electrical system. DC current will flow through the chassis for both RV and bus electrical, but both are still separate, since NO point of RV and Bus electrical have a common positive. Under normal conditions NO AC current will flow through the chassis of the bus. If you for sake of discussion had a power tool that developed a short between the HOT ac wire to the metal enclosure, current will flow to the ground wire (the third round pin of its plug) and cause the circuit breaker to trip. If any one is still confused, try an internet search for wiring of say a 1990 ford f250 wiring diagram. keep looking and you will find a schematic with a ground symbol. The term schematic is a term for a wiring diagram of an electrical or electronic device, such as a tv, radio, phone, etc. An internet search of "transistor radio schematic" should produce the following image:
In that image at the bottom wire is the symbol for ground. A lot of wiring diagrams for motor vehicles have that symbol. To me it is simple. AC ground is a green or bare wire connected in all circuits and in your electrical panel. In DC it is usually the chassis of the vehicle. Not all vehicles have a frame, but all have a chassis. AC ground only conducts with electrical failure (short to enclosure), DC in most vehicles ground /chassis carries current. Don't mix the two and you will be OK.
