What is general opinion on using this stuff on copper service entrance cables going into, out of meter base and breaker panels? i started using it on the threads and on the cables a while back in order to get more uniform tightening on clamps but here a lot of opinion both ways from my suppliers. Carroll
Our trade seems to have more than the average number of 'built in contradictions.'
Di-electric grease is quite often used to connect wires; just look inside any of those 'direct burial' wire nuts! For you motor-heads, it's also used on automotive ignition and battery connections.
As for mechanical threads on connectors and such ... the old 'trick of the trade' was to use anti-seize compound. These days, Noalox (and it's competitors) are actually listed for that use in addition for it's primary uses.
One advantage to using Noalox, or anti-seize compounds, is that they will NOT lead to you over-torquing the connection. (That was one of the criteria in their development).
I don't think I would use dielectric grease per say, but I wouldn't have any problem using something like the T&B inhibitor. It's a black grease like product that is made specifically for both copper and aluminum wires. Some people swear that dielectric grease will be dispersed when the conductors are torqued in the lugs, but I personally wouldn't feel comfortable believing that it makes a solid, low resistance connection unless the manufacturer specifically says it is okay for that application. These days I mostly use dielectric grease on things like battery terminals after the connections have already been made up and on the lip of spark plug boots to seal out moisture and prevent them from sticking to the plug insulators. Along time ago, we used it for sliding the rubber sleeves on primary load breaks, etc., but I haven't even been around anyone that does that type of work for years.
We had that discussion many times about teflon tape and screw in sensors and solenoids. We were assured by the engineers that there will always be a significant metal to metal connection once it gets installed to the proper torque. The same is supposed to be true in a binding screw termination. The action of tightening the screw squeezes out all the grease. You still should be using listed products tho.
Yes, I could see it not being an issue with Teflon tape and threaded sensors, but I think if it were me though, I would still want to see a hard copy of the white paper for that dielectric product stating that it is okay for the OP's application. It would be interesting to see a thermal IR comparison of the coated vs. uncoated lugs when the services are under heavier load, like in the summer when things like chillers, etc. are operating. I might just be me, but unless I can see it in writing, I would be concerned about how much area is actually conducting within those grease coated, round, smooth lugs they use in meter sockets.