Hot tub - MC or pipe?

[PetrosA]

I have a customer getting a hot tub that will be set outside on a stone patio. The manufacturer specifies that all wiring must be copper and that the EGC must be sized the same as the CCCs. Since they also require 50A OCP, it means that I can't use NM or UF anywhere in the run since the ground will be too small. It's about a 75' run from panel to disconnect to hot tub. The first 20 feet or so will be indoors above a dropped ceiling, the rest is outdoors under a deck and underground to the hot tub. Is pipe my only option or is MC an alternative? Locally I can get 6/3 MC with a #8 ground, and supposedly the sheath is a supplementary ground (page 9 here. Does that count to make the EGC the same size as the CCCs? Will the MC be in a damp or a wet location if it's strapped under the deck?

Am I missing a better alternative?

 

[augie47]

I have a customer getting a hot tub that will be set outside on a stone patio. The manufacturer specifies that all wiring must be copper and that the EGC must be sized the same as the CCCs. Since they also require 50A OCP, it means that I can't use NM or UF anywhere in the run since the ground will be too small. It's about a 75' run from panel to disconnect to hot tub. The first 20 feet or so will be indoors above a dropped ceiling, the rest is outdoors under a deck and underground to the hot tub. Is pipe my only option or is MC an alternative? Locally I can get 6/3 MC with a #8 ground, and supposedly the sheath is a supplementary ground (page 9 here. Does that count to make the EGC the same size as the CCCs? ?

#8 ground supplemented by a MC jacket is still a #8 in my book.
Letter of the law it is not the same size as your CCC, but your CCC would not need to be larger than a #8 unless your terminations are restricted to 60? so it's a judgement call.
(are you sure your MC has a #8 ground ? )

Will the MC be in a damp or a wet location if it's strapped under the deck??

Damp at the least... possibly wet................. Covered deck ?

Am I missing a better alternative?

pipe

 

[Dennis Alwon]

I would run pvc-- that always seems to be the easiest way for me.