12v DC tripping on panel

[smullis1961]

This just started this morning with the second main 12v DC breaker tripping. The amps appear to fluctuate but the lower 115 vac will sometimes drop to 0 and then back to 10 amps. I am attaching pictures of the panel. This is a 3607 88 Carver aft cabin cruiser. Any input would be greatly appreciated to resolve this problem.

[smullis1961]

In addition, I have noticed now that when you flush the heads(electric) the main breaker on the 12V DC trips immediately.

[km1125]

Don't get confused between the 12V systems and the 115V systems. They are totally separate and the only thing tying them together would be the battery charger. Your amp fluctuating on the 115 size is probably the water heater cycling on and off (as it should). You can verify this by just shutting of the breaker to the water heater.

On the 12V side, that second main just powers all the breakers on that line. Shut ALL those breakers off and see if the main holds. If it does, then start turning the individual breakers on one at a time.

If the main DOES NOT hold, then open the panel (there's a key above it that unlocks it, and the whole panel hinges down) and see if there's any wiring amiss on that second row. You could have something shorted there. Otherwise, it might just be a bad breaker in that "2nd row main" position.

[km1125]

Actually, re-looking at the pics, I see your water heater breaker is still off and you're still drawing 10A. Do you have a coffeepot or something else plugged into the outlets?? You can shut each one of those four breakers off to see where that 10A is being drawn from.

[km1125]

Source of the post In addition, I have noticed now that when you flush the heads(electric) the main breaker on the 12V DC trips immediately.

If that's the ONLY time it trips, then I'd explore if there's an issue with the heads drawing too much current. There are two separate heads... do they both cause this or just one. There should be a separate breaker for each head too, so you can isolate them from the main.

[smullis1961]

I have tried everything now, all breaker are off, exhaust fans off for the heads and it trips everytime I turn the main on the 12v panel

[smullis1961]

You are right about the coffee pot, as soon as I turn it on, it jumps to 10amps

[bud37]

You seem to have a short somewhere in the 12 volt side IMO. Like KM said go thru each user on the 12 volt side.

[smullis1961]

I turned off both 12v main breakers, and then turned on the 2nd main 12v and it still tripped

[km1125]

Source of the post I turned off both 12v main breakers, and then turned on the 2nd main 12v and it still tripped

If it trips with ALL the other breakers IN THAT ROW turned off, then it's either a bad breaker or a short behind the panel.