Doing something new… 400a service

[Sparky_Ed]

So I’m doing something a bit different. Designing a 120/240 400A service, using a Siemens meterpak 200a per position 2 position combo with the main shutoff/overcurrent right there in the meter. Feeding two separate 200a main lug panels, one in a retail space and one in an apartment. Was going to either use 600 or parallel 3/0 copper in 3” imc for the service. Not sure what to use for feeder. Without running a seperate ground I’m stuck between pipe or MC.

Was going to ground with two ground rods tied with #6 and a 1/0 to the building, gas, and water where applicable.

new to the forum, thanks in advance

 

[electrofelon]

Personally I would run two sets of 4/0 or 250 AL for the riser. If you were writing the check for this would you use copper? Feeders probably SER, or AL MC feeder cable.

Welcome to the forum!

 

[infinity]

Personally I would run two sets of 4/0 or 250 AL for the riser.

Separate raceways?

 

[electrofelon]

Separate raceways?

Probably same raceway. Of course with derating it wouldn't be a full 400, but doubtful that it needs to be.

 

[Sparky_Ed]

Personally I would run two sets of 4/0 or 250 AL for the riser. If you were writing the check for this would you use copper? Feeders probably SER, or AL MC feeder cable.

Welcome to the forum!

Thanks for the reply, going to consider both. Looks like it’s almooooost half the price for the service entrance conductors.

I don’t like the idea of SER with metal framing but what are ya going to do MC ain’t cheap.

 

[Sparky_Ed]

Separate raceways?

Can you explain this section of the code better?

thanks for the input!

 

[infinity]

Can you explain this section of the code better?

thanks for the input!

With installing more than 3 CCC's in a single raceway you would need to consider derating.

 

[electrofelon]

Thanks for the reply, going to consider both. Looks like it’s almooooost half the price for the service entrance conductors.

I don’t like the idea of SER with metal framing but what are ya going to do MC ain’t cheap.

Actually I recently purchased both 4/0 SER and some 4/0-4 MC and I think the MC was cheaper

 

[Sparky_Ed]

Actually I recently purchased both 4/0 SER and some 4/0-4 MC and I think the MC was cheaper

Waiting for a quote comparison Monday. I’ll make sure to share pricing

 

[kwired]

Actually I recently purchased both 4/0 SER and some 4/0-4 MC and I think the MC was cheaper

Conductor composition of either is essentially the same, plastics in sheathing is probably higher cost lately than metallic sheathing.

Kind of been that way even with smaller sizes of MC cable vs NM cables for a while now, so wouldn't surprise me to see it similar with larger cables as well.