I ordered a Cutler Hammer 400 amp twin meter, the box had obviously been opened before I got it(since the staples weren't secured)anyway upon opening the meter base I discovered the utility side didn't have lugs for the linemen to connect to. I called my vendor and he ordered me the lugs for it(at my cost), he said they are sold separately. I have some issues with the fact that 1. I have never had to install lugs before on a meter base and find this peculiar. 2. He said the lugs came with phillip screws...how can I possibly torque these enough that there won't be any vibrations on a 400 amp bus/lug? Am I being too worrisome, because I have seen what happened on a 200 amp service that had a bolt from the main breaker(from the factory) to the bus which got glowing red because it was a turn and a half lose. Whats your guys thoughts? Thanks, H2o
In these parts, our predominant POCO actually prefers 3/8" studs with nuts for them to make their own final connections. They don't want lugs at all. They even supply meter sockets for 320A and below for residential use at no charge. They do the line and load side terminations using Hypress terminals, so all we do is leave the cable hanging there for them. With overhead services, they even furnish & install the upper part of the SEU cable on 200 amp services or smaller.
I must say that I've never heard of lugs rated for 400 amps that are only secured by single Phillips screws. I'd say maybe a 1/4" flat head that requires a #3 screwdriver might suffice, but I agree that the vibration issue would leave me wondering as well.
I think he probably means the large flush head Philips screws that run through a hole in the back of the lug to secure it to the bus. Those lugs usually have one or two raised ridges that overlap the bus or some other means to prevent side-to-side movement when you torque down a conductor.