MV cable

[stuartdmc]

I have a client that's asking the question what size 5kv direct burial cable should be used to feed a EOX 115 Motor = 3209 hp motor?

I could use any help I can get.

Thanks.

 

[rcwilson]

Thermal resitivity of soil? Nameplate amps? Depth of burial? Other circuits in close proximity?

 

[weressl]

I have a client that's asking the question what size 5kv direct burial cable should be used to feed a EOX 115 Motor = 3209 hp motor?

I could use any help I can get.

Thanks.

I presume that this is a 4000V motor. I would really like to see that at a higher voltage because the current and the large copper it will result in.

http://www.okonite.com/Product_Catalog/section2/section2-pdfs/2-22.pdf

I also don't like to direct bury aluminum, even though it has an overjacket. (Unfortunately led covered cables are no longer available and the Phellps/Dodge corrugated bronze substitute just never taken hold.) Eventually polymer will saturate and the chemicals, mainly alkalies, present in the ground attack the aluminum and there goes your cable. Years down on the road, but it will happen. As far as the sizing goes, you need to have the nameplate current and size it according to the NEC and the manufacturers current rating. You may be able to get away with a single 500kCMil/phase, or multiple smaller ones per phase.