Thread: Rainbow effect in a newer panel

This is off of an 06 house. Any idea what the cause of this 'rainbow' effect on the neutral/ground bar is from? Or more to the point, I know it's from heat, so what is causing heat? I checked several of the lugs and was able to put maybe 1/4 turn on some but they didn't really feel terribly loose.

I told the buyer to get an electrician as it's not normal.

Similar Threads:

• air gap in newer dishwashers
• New Pool Safety Mandate in Effect - Cooperator
• Air Conditioning, Ambient Temperature and RLA Effect
• Cracking at newer shingles
• Feed From Main Panel to Sub Panel

All I see are variations in the colors of the screws ... and some improperly twisted ground wires (two can most likely go in one terminal, but not twisted).

Im guessing anodizing

The pictures don't do it justice... that's why I tried one with the flash and one without... There is a rainbow effect on some of the screws and the bar itself. The copper wires that are attached to the suspect screws are kind of a dull color... they definintely stand out from the other wires that are shinny copper color.

You can see the darkened wire the most on the lowest visible one pictured on the bus bar.