DrewE wrote:
westend wrote:
I'll go against the "right hand wires" theory in this. It appears the neutral bus was connected to the load center correctly with the three mounting screws. It appears that every wire has lost jacket material from heat, the right side being the worst. I would guess that the cause is a loose connection within the load center to the shore cord or a failing shore cord that allowed connection but a lot of resistance.
I'd suggest to check resistance of the whole neutral path from the male neutral plug end to the neutral bus.
One of the wires connecting to the neutral bus is the wire from the shore power cord (possibly via a transfer switch). From the picture, it looks like it's the rightmost connection, as that's a 10 gauge wire, verifiable by the orange outer jacket of the romex where it enters the electric box (as well as by its comparatively larger diameter). The hot from this wire goes to the uppermost breaker, which conventionally would be where you'd put the main breaker, and which further tends to confirm that this is the input wire.
The heat is not coming up the wire from some poor connection further down, as the hottest parts were clearly near the bus bar. If it were from a poor connection further down, the wire would be more burned further down.
To my eye, the second position in on the right with the doubled-up wires appears to be the culprit, but that's rather a moot concern at this point. It needs to be redone for safety regardless.
After reading your post and looking again, I humbly remove my first diagnosis. The heat is certainly centered towards just a few lugs. Your diagnosis would be the most plausible.
Thankfully, it appears the OP has enough usable wire to install the new bus, strip wire, and start over. I've bought bus bars at the big box stores but an electrical distributor will have better ones. It is probably an orderable replacement part from the MFG, too.
