Saw this on an inspection today. Overheating?

The top of this buss bar looks heated or scortched to me. The subpanel is a Sylvania and its about 32yrs old.

Ok discovered this is a Zinsco/Sylvania. Ive never seen on in the process of failure. Have notified the homeowner and have noted in the report.

That is a heat mark caused by the blade used to cut the bus bar during manufacturing of the panel components.

The heat mark is not a notable defect, and is not indicative of any type of failure of the panel.

The mark is not a Failure…
The fact that the Panel is Sylvania / Zinsco warrants a recommendation for replacement.

No anti oxidant paste also

Ok I can see how it might be a manufacturing issue but how does one know the difference?

So? It may be a good pratice, but is not required.

Think about it this way, if the heat was high enough to scorch the end of a busbar that is not near a bolt, screw or breaker connection, the damage at the actual bad connection would have to be massive which would be very noticeable.

There are some cases where discoloration can be caused from lightning surges but those will usually be black or pitted from arcing.

I usually do the touch test. If I can hold my finger on it for 3 seconds, it’s not to hot. :twisted: