120 Volt Breaker Issue

[trailrider]

Two breakers in the equation. 15 amp breaker runs the refrigerator outlet. Another 15 amp breaker runs the microwave. The refrigerator breaker trips occasionally when running the microwave. Messed around with the breakers and here is where it gets weird. The refrigerator breaker feeds the microwave breaker somehow. If the refrigerator breaker is off, the microwave breaker doesn't supply power to the microwave when you flip the breaker on. How is this even possible?

[trailrider]

And just to explain it a different way. All breakers are on.

Turn off microwave breaker, microwave display goes out.

Turn off refrigerator breaker, microwave display goes out and refrigerator 120 volts outlet is dead. Verified because refrigerator switches to gas mode.

And since the refrigerator breaker is tied to both outlets for the refrigerator and the big convection oven/microwave this 15 amp breaker will trip occasionally. Which my guess is if the 300 watt refrigerator heating element happens to be on at the same time the microwave is in use it trips.

[BFL13]

The Canadian version of the 03 Komfort has the MW and water heater on the same 7355 circuit and the one breaker, but there is only the one black wire going to the bottom of that breaker. There is another wall switch that has three positions for the WH and MW, which are : WH, Off, MW.

The USA version of the 03 Komfort 7355 does not have that, but has a different arrangement for the 120v breakers, and uses 20s instead of 15s a lot.

Perhaps the now gone RV had something like that with a downstream switch between the MW and the fridge, away from the single breaker.

EDit--ok forget that, the MW had its own breaker.

[trailrider]

enblethen wrote:
30 amp fed from inverter?
Make and model of "inverter"?
This is in an 03 Komfort?

This was on a diesel pusher motorhome that I checked out briefly for someone passing through. It's gone now so I can't look at it again. I was just trying to see if anyone had run across this specific problem so I could learn something. I just don't see how it's possible in a breaker panel when each breaker is supplying it's own specific outlet.

[enblethen]

30 amp fed from inverter?
Make and model of "inverter"?
This is in an 03 Komfort?

[trailrider]

enblethen wrote:
Look for the larger #10 wire coming from the shore power cord. Many go to the screw terminal on a 30 amp breaker. This feeds the rest of the breaker via the buss work.
The screw terminals on the 15 amp breakers feed the device/receptacle.
I am guessing that some one replaced the 30 amp breaker with a fifteen amp.

This has a 30 amp breaker on the far left side that is fed from the inverter.

[trailrider]

BFL13 wrote:

trailrider wrote:
It is a 30 amp sub panel fed from the inverter. I already took the cover off and verified that each breaker is wired to it's own separate romex. Once those romex leave the box I have no idea what happens down the line.

"Verify" means turn everything off and see what works and doesn't work when you turn on each breaker. Takes a few minutes. Take notes each time. You could be surprised! 😞 (Trust but Verify!!!!)

Yeah, I already did that.

[enblethen]

Look for the larger #10 wire coming from the shore power cord. Many go to the screw terminal on a 30 amp breaker. This feeds the rest of the breaker via the buss work.
The screw terminals on the 15 amp breakers feed the device/receptacle.
I am guessing that some one replaced the 30 amp breaker with a fifteen amp.

[BFL13]

trailrider wrote:
It is a 30 amp sub panel fed from the inverter. I already took the cover off and verified that each breaker is wired to it's own separate romex. Once those romex leave the box I have no idea what happens down the line.

"Verify" means turn everything off and see what works and doesn't work when you turn on each breaker. Takes a few minutes. Take notes each time. You could be surprised! 😞 (Trust but Verify!!!!)

[trailrider]

It is a 30 amp sub panel fed from the inverter. I already took the cover off and verified that each breaker is wired to it's own separate romex. Once those romex leave the box I have no idea what happens down the line.

[BFL13]

You need to expose the breakers by removing the cover plate. OK, now look at the black wires going into the bottom of each breaker. Sometimes there will be two black wires going to a breaker, so it "shares" circuits.

If that is what is going on here, you can snip black wires and shuffle which goes to which breaker to achieve a more happy combo.

The OEM labelling as to what breaker does what cannot be trusted---verify, and re-label as required

[Boon_Docker]

Sounds like someone was trying to connect two 15 amp breakers to make it 30 amps, but wired them in series.

[Matt_Colie]

Trail,

How many breakers do you have?
Are they in a distribution panel?
Is the unit a 30Amp service?

I think something is seriously screwed up, but I sure can't tell from here exactly what it is.

Matt