the manual/manufacturer should give you details, based on your tub. A lot depends on whether you have a heater or two, big pump or two, can they both run at the same time - full tilt and whether you are planning on 240/120.
then you can do lengths and size
I have 6 gauge. It might turn out to be 8 once you get beyond "general idea".
Not an electrician...just a guy that has a hot tub.
I think you need #8 wire if copper.
I had an electrician wire mine up. He took the required 240V to a disconnect near the hot tub and the tub itself wired to the disconnect. The disconnect and the breaker are both 50 AMPs.
Please check my answer with others before proceeding.
Phil
Mine is 8/10 and was spec'd as good for up to 100ft run by the manufacturer. 50 amp.
BUT my tub is setup differently in that at the shutoff box near the tub it splits the 50 amp into a 20 and a 30 amp circuit, so im guessing the whole 50 is never or rarely ever used.
Look into what your tub manufacturer recommends.
If you know no other specs than "50 amp at the tub location" than run 6 gauge...
If you can get more detailed info from the hot tub manufacturer, you might be able to get by with 8 gauge.
If the manufacturer or dealer cant tell you anymore than "50 amp service near the hot tub" I would be leary of them overall. Should be in the owners manual what electrical service requirements there are.
Wouldn't the length of the run dictate the wire size? How do they know how far it would be?
If you know no other specs than "50 amp at the tub location" than run 6 gauge...
If you can get more detailed info from the hot tub manufacturer, you might be able to get by with 8 gauge.
If the manufacturer or dealer cant tell you anymore than "50 amp service near the hot tub" I would be leary of them overall. Should be in the owners manual what electrical service requirements there are.
Its in the manual. 240V/50A. I dont see why its their responsibility to tell me how big and how far that size wire can run. They are hot tub designers/builders, not electricians. It says the max wire size for the attachment is 6ga. I read that as it could be smaller if situation warrants it?
What other detailed info would I need? They have a bus bar for a neutral, and two hots, and a ground. I assume they divide the power up after that to each motor, heater, etc??
You are correct. Circuit ampacity and voltage are all any manufacturer of any type of equipment is going to give you. Amperage is not going to depend on length, or any other factors. If the manual says 240V, 50A, then that's all the info you need. To answer your question, the wire size will depend on what type of wire you are using. If you're using nm/b (Romex) then #6 is required. If you are using conduit and THHN, then #8 is acceptable. FYI, you'd get much better answers if you put this in the electrical sub forum.
Thanks, I got my answer.
I always thought current draw did dictate wire size, i.e. why do I need a bigger extension cord for longer runs, than shorter ones. How does the electricity know if its 5' or 500'?
resistance in the wire. The longer the run the more the voltage drops. A heavier gauge wire has less resistance generally all other things considered like quality of the copper etc..
You are correct. Circuit ampacity and voltage are all any manufacturer of any type of equipment is going to give you. Amperage is not going to depend on length, or any other factors. If the manual says 240V, 50A, then that's all the info you need.
FWIW...#6 will deliver 50 amps out to 163 feet.
Assuming it is just a plain tub, not a time machine version....
Also, if this is a 'stand alone' location, you may want to run a 20A (or15) circuit for light, receptacle, etc. in addition to what the tub needs
It is pretty easy to find specs for X amp load requires Y gauge wire. But then the distance needs to be factored in. I found this out the easy way about 40 yrs ago when I burned up the motor on my radial arm saw. The repairman looked at it for about 10 seconds and says, 'you been running this w/ an extension cord haven't you?'. Guilty. I made a new extension cord from a 25ft roll of romex. It was always kind of a pain to use but I haven't burned up any motors since.
FWIW...#6 will deliver 50 amps out to 163 feet.
Assuming it is just a plain tub, not a time machine version....
Also, if this is a 'stand alone' location, you may want to run a 20A (or15) circuit for light, receptacle, etc. in addition to what the tub needs

Thanks, I got my answer.
I always thought current draw did dictate wire size, i.e. why do I need a bigger extension cord for longer runs, than shorter ones. How does the electricity know if its 5' or 500'?
for the time machine version, you will need to call the power company and put in a separate meter![]()
