Unable to ground the battery

[hamiltonmj]

I am redoing a 1965 Caravel. The Univolt did not work so I installed a Progressive Dynamics unit. The battery is wired to the PD unit. However, I am unable to ground the battery to the Caravel frame because when I try the fuse for the lights blow....making me think I have a problem. Each system works fine separately...I mean the 120V works when hooked up to shore power and the 12V lights and fan and the battery gets charged but I should be grounding the 12V battery to the frame of the Airstream but "can't" because of the light fuse blowing. Help me understand this one. Thanks.

[BambiTex]

If the PD unit is grounded to the frame, I think you just connect both battery terminals to the converter directly rather than to the frame.

[Melody Ranch]

Don't try to be inventive.

[87MH]

You may have a negative side fuse in the fuse panel.

The '78 Sovereign has two of them. Check the wiring around your fuse panel.

[hamiltonmj]

I figured it was one of the lights so I started undoing and de-reviting the lights and the fan and the water pump (all work on 12V). Of course, the last one was the overhead light by the door and it was the culprit with a wire touching the frame. Now I can ground the battery...thanks.

[cwf]

Note to self:
When wiring many things to one circuit, have a way to "split" fore/aft, port/starboard, etc. this way you can "isolate" circuits and possibly be able to get "some" of the circuit online so you are not totally dead in the water.

I did that on my MC, aircraft, boats, cars and now AS!!!

Of course this is all "overkill" until you need it.