Hot tub wire size

[olly]

Can someone help me understand why #8 CU can be used for a hot tub on a 50A breaker. 110.14 (C)(1)(A) says you have to use the 60* column. I have not wired many hot tubs. When someone wants the wiring in before they have the tub would you run #6 CU to be safe or is #8 CU standard?

I assume #8 can be used because the hot tub is only pulling 40A? But I am guessing. Please let me know

 

[kwired]

Can someone help me understand why #8 CU can be used for a hot tub on a 50A breaker. 110.14 (C)(1)(A) says you have to use the 60* column. I have not wired many hot tubs. When someone wants the wiring in before they have the tub would you run #6 CU to be safe or is #8 CU standard?

I assume #8 can be used because the hot tub is only pulling 40A? But I am guessing. Please let me know

If running NM cable it would have to be 6 AWG because NM cable must use 60C ampacity.

However if other cable or conductor types 8 AWG ampacity @75C is 50 amps. Terminations also need to be 75C but that is almost guaranteed anymore that they are 75C. 30+ years ago they may not have been.

In a dwelling application it is kind of common to run 6 AWG NM cable from the panel to the disconnect, then 8 AWG THHN/THWN(-2) from disconnect to the unit for a 50 amp circuit.

 

[olly]

If running NM cable it would have to be 6 AWG because NM cable must use 60C ampacity.

However if other cable or conductor types 8 AWG ampacity @75C is 50 amps. Terminations also need to be 75C but that is almost guaranteed anymore that they are 75C. 30+ years ago they may not have been.

In a dwelling application it is kind of common to run 6 AWG NM cable from the panel to the disconnect, then 8 AWG THHN/THWN(-2) from disconnect to the unit for a 50 amp circuit.

That's a head slapper, I always forget that rule is for NM cable. Thank you! Does an outdoor hot tub require an outlet. Artical 680.40 clearly says an interior hot tub requires a general use outlet. Can you verify that same goes for an outdoor? It makes me wonder why spa disconnects don't come with a 120v GFCI? Sorry for the rookie questions...

 

[AC\DC]

Yes don’t have code section but you need an service receptacle. Not closer that 6’ not father that 25’ I think.
Hot tubs have to apply to section 2 and 3 of articles 680.
Should state that the section with hot tub. Everything I stated from memory so do look then up

 

[guschash]

I don't like to second guess myself . I read the manual and see what the manufacturer wants , #8 or #6. I done some hot tables where #8 is all they are asking.

 

[kwired]

I don't like to second guess myself . I read the manual and see what the manufacturer wants , #8 or #6. I done some hot tables where #8 is all they are asking.

I seen some that say to use #6 yet they hardly give you room for it.

If a used tub, I probably will still run #8 can't void a warranty that is already expired.

 

[kwired]

Yes don’t have code section but you need an service receptacle. Not closer that 6’ not father that 25’ I think.
Hot tubs have to apply to section 2 and 3 of articles 680.
Should state that the section with hot tub. Everything I stated from memory so do look then up

680.22 - applies to all swimming pools, spas, etc. says no less than 6 feet and no more than 20 feet.

680.43(A) applies to spas located indoors changes it for that specific situation to no less than 6 feet and no more than 10 feet.

That's a head slapper, I always forget that rule is for NM cable. Thank you! Does an outdoor hot tub require an outlet. Artical 680.40 clearly says an interior hot tub requires a general use outlet. Can you verify that same goes for an outdoor? It makes me wonder why spa disconnects don't come with a 120v GFCI? Sorry for the rookie questions...

There are many times if the receptacle were included in the disconnect it may be too close to the spa, though said disconnect still needs to be at least 5 feet away (from water's edge).

 

[AC\DC]

5' off, Thanks for that Kwired I should of posted them for him when I got home.