Electric demand meter and 120v red legg?

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ritelec

ritelec

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Jersey
Old service entrance conductors are brittle and need replacement in rigid conduit

The system is red leg. They lost phase A. RED leg in old meter pan ( the terminals are on the bottom and meter on top) is on B phase in meter. Although it should be in C phase I was planning on putting it back where it is on B phase. Some reading I see says B needs 120v for meter.

Leave it on B as it is or switch to C phase.


Second question please. #2 cu thhn/thwn for 100 amp correct.

I measured existing rigid which seems ti measure od 1 3/4

The existing cloth wire measured about 7/8 od

I was going to do #1 bit at the supply house I'm questioning if the existing pipe is 1 1/4 or 1 1/2 ??

I'm good with 2's in either.

2's for 100 amp right ?


Thank you
 
Not sure what "red leg" means. Many used to mark a delta high leg Black-Red-Blue, with red being the high leg (208V to neutral/ground). Is that what you mean by "red leg"?

As I understand it, many of the older meters require the high leg to be on C.

If the meter is not being replaced, match existing.

If meter is being replaced and require the line-side phases to be flopped, flop the load-side phases to match. Do not flop anything at service disconnecting means (i.e. assuming the high leg is on B both before and after).
 
#2 is good for 115A before derating if you have 75°C-rated terminations.

#2 is good for 95A before derating if you have 60°C-rated terminations.

The latter is good on 100A OCPD as long as the load is not greater than 95A, assuming any derating does not lower the ampacity and not less than 91A.
 
Ok thank you. The wire actually goes into a through after the meter and bugged to two panels

One panel is 100 amp 2 pole breaker main added on in 79 which has a passed elec sticker. The okder is 3 phase main lug 100.

My bust on the meter. C phase is the high legg.

2's are going in

Headed to the roof to cut brittle wire.

Watch out for arcs and sparks.

Playing. But I am truly nervous.

Later


Thank you
 
Smart $ said:
Hopefully, you are "playing".

By the time you see arcs and sparks, it's too late!!!
Click to expand...

Understood.

Thank you. I survived.

Little tough getting old wires up and out. But got them out. Couldn't get new once in. The rigid goes below grade to the meter in the basement. Was an old bar.

The phases where all hot at the head. Lost phase was in the pipe at the 90 going in below grade. The phase just disintegrated and burnt itself upart in the conduit.
It was also filled with dirt from a few rust holes that dirt and water came in over the years.

Had to pull out a sledge hammer and shovel. Got below grade out to meter pan. Will replace it tomorrow.

Yes the arc and sparks. Was dumb but I did it. God was watching.

Thanks again for the concern.

Rich
 
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