VD On AL MC Cable

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Alwayslearningelec

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I have 2000A switch feeding a 2000A board. 3P4W 120/208V.
The run is about 700' long. With 6 sets of 750 Al MC cable I'm getting 12% voltage drop.

Is that correct?
 
electrofelon said:
With that much length, I'm sure he could get a custom cable made with the proper egc.

Sadly, I already know for sure that I will be busy the day of the install and won't be able to help pull that 750-4 MC 🤣
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Around 2800# per 700' cable.. piece of cake !
 
augie47 said:
Around 2800# per 700' cable.. piece of cake !
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I have used 250-4 MC in short lengths. The worst was 2 parallel 4/0-4 AL MC about 150' across the ceiling of a high bay warehouse by myself. It was not a pleasurable experience. Cant imagine 750.

Cant help but wonder if higher voltage would help here..... :unsure: . Bring in a 480 service and step it down at the end?
 
All the info I have is they want a temp 2000A feed(3P 4W 120/208V) from a a extg. service switch to a 2000A dist board ~700' away. Mostly vertical.

I had a thought..lol. Maybe step up to 277/480v at the source then back down at the dist panel?? Then again doesn't matter they're asking for 2000A. But that would be different @ 277/480...sure less????

Anyway maybe just EMT and THHN.
 
Even EMT and THHN is going to be a serious effort.

Maybe price up a transformer and see what the numbers come out.

I wonder if you could get that poco to just run MV to the vicinity of where the service needs to actually be.
 
horsegoer said:
All the info I have is they want a temp 2000A feed(3P 4W 120/208V) from a a extg. service switch to a 2000A dist board ~700' away. Mostly vertical.

I had a thought..lol. Maybe step up to 277/480v at the source then back down at the dist panel?? Then again doesn't matter they're asking for 2000A. But that would be different @ 277/480...sure less????

Anyway maybe just EMT and THHN.
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I would try to figure out approximately what the actual current draw will be. Maybe a discussion with the client about how much it is going to cost them to just throw out some unrealistic number would make them give you a more accurate figure?

Bumping up to MV would be the ticket, if you are using transformers no point in sticking with 600 volt. But you have to weigh the cost of the transformers. I'm guessing a 500 KVA transformer is going to be about 16k each.
 
2000 A at 208 V is about 100 A at 4160 V. Maybe the poco would get him a 4160 service that he could just run over there and put a transformer at the end.

The nice thing about EMT would be no worries about having to run a ground wire.
 
petersonra said:
2000 A at 208 V is about 100 A at 4160 V. Maybe the poco would get him a 4160 service that he could just run over there and put a transformer at the end.

The nice thing about EMT would be no worries about having to run a ground wire.
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I did price out aluminum MC feeder cable versus aluminum in EMT before, and if I remember correctly the EMT is cheaper, but of course there's the labor....
 
One more thought about transformers: presumably you wouldn't have to buy new for something like this, you could just get something off of eBay, or from one of these used/refurbished transformer companies. some of these places rent transformers, so that could be investigated.
 
Thanks guys so if we step up to 480v, then step down at the 2000A panel how do you about calculating xfmr and conduit/wire & # of sets? Thank
 
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