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jmoyles's avatar
jmoyles
Explorer
May 06, 2014

Wiring in a volt/amp meter

I'm going to put a volt/amp meter in my PUP, and realized I might have an issue with my design.

Original Design:


This design had me placing the shunt for the amp meter *after* the negative ground to frame. I'm thinking that this will keep the amp meter from measuring anything that uses the frame for the ground side, as the circuit will flow from the positive to the device to the frame ground and back to the battery.

If that theory is correct (let me know if I'm wrong), then I'm thinking about moving the frame ground to after the shunt, which I believe will solve this problem.

Updated Design:


Am I on target with the new design, or am I still missing something?

PS: Two 12V batt's, wired in parallel are the power source.
  • Thanks lasttruck - that's what I figured, but wanted to verify.
  • The only thing on the battery side of the shunt should be the battery. Everything else goes on the other side, including the meter ground.
  • Couldn't follow all that but what's wrong with a portable unit that can be used in other places as well.