Can (or should) the 12-volt negative wires at the Parallax converter station on the coach be grounded to the metal chassis of the RV? And won't this be a problem? I'm doing some remodeling on the electrical system and I noticed all the DC wires on a single lug block screwed to the wood of the floor. I thought this was odd.
Mike, (Boise, ID)
Mike, (Boise, ID)
Mike, yes, the 12-volt negative terminal block on every converter should be grounded to the same metal component as the negative cables on the batteries themselves, usually the vehicle frame. It does nothing, (but keep them in one place), to have them screwed to a wooden floor. In addition to the negative 12-volt conductors, the metal converter chassis should also be “bonded” to the frame using an 8-gauge conductor. This conductor may be uninsulated and it could also be a solid copper conductor. The negative 12-volt conductors, however, must be stranded. Now all that said, it is entirely possible that even though all the wires you see going to that single terminal strip are attached to the wood floor, one of them might actually go down to the frame, thereby making the connection and grounding those circuits. A simple continuity test with a VOM will confirm this.