Fire Engine Electrical question
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Fire Engine Electrical question
I guess this would relate to cars as well; we have a 12V neg. ground system, just a few extra batteries.
We have a portable suction unit that has a plug to keep it charged. There is a hot single wire running toward it, then it's spliced to the double wire plug end at the suction unit. Someone cut the second wire and just grounded it to the body with a screw. Doesn't the ground have to come from the power side? Is it doing anything? Thanks, I have to rewire it today to a new location.
We have a portable suction unit that has a plug to keep it charged. There is a hot single wire running toward it, then it's spliced to the double wire plug end at the suction unit. Someone cut the second wire and just grounded it to the body with a screw. Doesn't the ground have to come from the power side? Is it doing anything? Thanks, I have to rewire it today to a new location.
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does this portable unit contain its own battery and is it being charged by the vehicle or by 110 volt plug in?
if its being charged off the vehicle the ground would go to a known good ground whether to the negative side of the battery or on a 12 volt neg ground vehicle on the frame or good metal ground seeing how it is portable it may not have a very good ground on the unit itself.
on 12 volt positive ground vehicles the positive would be ground but not likely on any vehicle unless it was built in the 50's or early 60's.
if its being charged off the vehicle the ground would go to a known good ground whether to the negative side of the battery or on a 12 volt neg ground vehicle on the frame or good metal ground seeing how it is portable it may not have a very good ground on the unit itself.
on 12 volt positive ground vehicles the positive would be ground but not likely on any vehicle unless it was built in the 50's or early 60's.