Oily substance found on circuit breaker

[madchad]

During a routine panel PM I found an oily substance on 3p 40a 208v ckt breaker which is identified to feed a duct heater. All surrounding devices are clean, dry and in good condition. What may this substance indicate?

 

[Jim W in Tampa]

I have seen some that are bit nasty feeling after years of use. Not sure if it is actually oil. Would check to see if breaker is running hot from bad connections and might be smart to replace it since your already on the job.

 

[jim dungar]

Molded case circuit breakers do not contain any oil or grease that could leak out of them.

Your oily substance is most likely coming from your conductor's PVC insulation. Do a search for electical insulation plasticizer.