DC ground

[Talonewo]

My boat has 12 and 32 volt DC systems. At the distribution panel each has its own ground bus bar. They are NOT connected, I checked with the continuity tester on my volt meter no tone. Yet I checked all battery banks are grounded to the engine block. If both the 12 and 32 volt systems are grounded to the engine block why aren't the bus bars comin? What am I missing?

 

[Capt.Bill11]

Diodes?

 

[Lobstah]

I think Capt. Bill is probably right.
Have you check with your tester from block to each bus? Seems like an odd setup.
What do you have that uses 32VDC?

Jim

 

[C lectric]

Have you actaully confirmed that the battery bank busses to engine block conductors are good. Maybe one of them has a problem. it would only take one.

 

[Talonewo]

sorry for the delayed response, work and life got in the way of Boat. To answer your questions, just about everything is 32v on the boat, all pumps, windlass, nav lights and fans and each room has 32v and 12v lights. As for the 12v batteries to the block I can't find a wire but checking with the continuity tester there is continuity from the 12v neg to the engine block.

What started this issues was I switched two things from 32v to 12 volts, the small air compressor for the horn and the inverter. When I did it I just changed the positive wire of each and left the corresponding neg wire connected to the 32v negative bus bar at the power distribution panel assuming the negative of the two systems were connected. For both pieces of equipment when connected to the 32v ground and the 12 volt power with no load they would have the full 12v voltage (anywhere from13 to 14.2 depending on what the charger was doing) but as soon as I turned on the compressor or used the inverter the voltages would drop to anywhere from 9 to 12 volts. If I fired up the main engine everything worked fine. As soon as I moved the negative wire for the inverter and compressor to the 12v neg bus bar the both work perfectly...