connection hardware to use to connect to a copper busbar

[michaelsharp]

we have a copper busbar that is 1/4 thick and 4 inches wide and of sufficient length to accommodate the number of terminations necessary for the installation. Question is what type of hardware is required to bolt the compression lug to the busbar? does it have to be copper bolts and washers or can steel or galvanized hardware be used?

 

[don_resqcapt19]

Typically grade 5 carbon steel hex head bolts with flat washers, a lock washer and a nut is used for that purpose.

 

[petersonra]

we have a copper busbar that is 1/4 thick and 4 inches wide and of sufficient length to accommodate the number of terminations necessary for the installation. Question is what type of hardware is required to bolt the compression lug to the busbar? does it have to be copper bolts and washers or can steel or galvanized hardware be used?

there is no need to use copper bolts. I don't even think you can get them made of copper anyway. I suspect what you think are copper are really bronze.

The fastening means is not part of the current path so it does not even need to be conductive.

You can use whatever hardware to fasten it to the bus bar that is appropriate. Often the manufacturer will tell you what is appropriate or you can figure it out for yourself based on what torque is required. Usually this means some kind of steel bolt is most cost effective. As for being galvanized, probably is not necessary. The copper bus bar will oxidize more than ungalvanized steel will. But it might make sense to just standardize on using galvanized fasteners so you don't have different fasteners around. The cost is often about the same.

 

[electrofelon]

I agree with what the others have said. I typically use grade 5 or grade 8 hex bolts. The only thing you will find code wise for guidance is possible 110.3 if there are any instructions with the lug.