Foreign substance in panel box wiring

Can someone please review the attached photo and tell me if this is ok? I’ve never seen this before.

This was discovered in the panel box. Owner is stating that the substance on the 2 wires is for the aluminum wiring going to the outside building. He stated that it is code because of the aluminum wiring.

Looks like hot glue from a glue gun… The type I used to use in my electronics business to hold small wires in place

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I thought the same! Is it ok to be on there though? Owner stated that it was “code”.

Hi Scott

Looks like a Silicone Dielectric Grease to me. It is used to protect electrical connections from corrosion by repelling water and sealing out air. It is most commonly used on car battery connections but will protect any electrical connection just the same.
Hope this helps.


that I do not know. I would recommend an electrician to further evaluate.

Is that the main for the panel? Almost looks like they tried to insulate the connectors so there is a reduced chance of shock when the main is turned off.

What made me think of glue was the tail on the bottom 1/2 of the breaker. that is typical of the glue gun trigger being released and pulled away. Would Silicone Dielectric Grease stay like that for an extended period of time?

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Thank you! After speaking to an industrial electrician friend of mine, he stated the same.
I’ve never seen it before.

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That’s what I stated. Learned something new today.

I’ve never seen it used in electrical panel before now thank you for posting this Scott.

Whatever that is… might be approved to prevent corrosion of Aluminum Conductors, (might be required by some codes and or the manufacturer of the Panel/Breaker) when using stranded aluminum… But it needed to be applied to the conductors so it would coat them and the breaker lug. The application is wrong and does not do anything except make HIs scratch their heads and say WTH? If I had to guess someone called this out as needing the anti-corrosion applied, but was done by the homeowner or uncle Frank…not understanding the reason for it.


Yep. The screw head is not the conductive contact point. It’s where the conductor enters the terminal. They would have had to pull the conductors to apply dielectric grease or anti-oxidant where it needs to be. Somebody was just pretending to do something useful.


Does not look like it’s going to hurt anything, but when they say “code” I am curious to what section is the reference?

Looks like anti-oxidant paste. Very common and shouldnt be an issue. When it gets older it will appear crusty. Normally it goes on the wire though… looks like they just put it on the screw

I don’t think so.

I think it is there so no one can remove the screws without extra effort…

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It looks like antioxidant for aluminum. But it does no good where it’s at. Can you tell if there’s any around the wire at the connection point. If not that is a defect.

I couldn’t verify much due to the location and limited view. After further research and the replies in this thread I agree that the antioxidant was applied incorrectly.

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Does anyone know what brand of anti-ox looks like that? The stuff we use is charcoal gray.


There isn’t any that I know of… That is why I said " I don’t think so".
That is silicone caulk.

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whatever it is, it was not applied as a dielectric grease.