Hot Tub Wire Gauge vs Length


Old 10-21-03, 07:19 PM
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Hot Tub Wire Gauge vs Length

I recently purchased a hot tub that requires a 50 amp breaker, and 6 gauge wiring (2 hot, 1 neutral, 1 ground - ALL as 6 gauge).
My question for anyone who can help or answer is the wire length to the GFCI disconnet is about 55 feet in conduit, then from the disconnect to the tub is about 40 feet in conduit. I recently read something to the fact that if your total wire length is greater than 75 feet you should go up the next level in wire guage to conter the voltage drop over distance. Any help in this regard would be great since 4 guage is twice the cost of 6 guage wire. ( my understanding it is legal per NEC to run FOUR 6 guage THHN wires in 3/4 conduit?)...Thanks for the help!
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Old 10-22-03, 07:33 PM
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Hello flyingtooth. Welcome to the Do It Yourself Web Site.

I moved your question into this electrical forum, since the question pertains to the electrical wiring, than the actual spa.

I am sure the professional electricians in this forum will be able to provide you with the help and advice needed.
Old 10-22-03, 07:43 PM
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Voltage drop calculations involve the voltage, load current, wire size and length.
#6 copper (I assumed copper) at 240V, 40A of load and 95' results in approx 1.5% voltage drop. Generally, below 3% is acceptable. When you get close to 175' with your circuit, then you will be approaching 3%.
So ..... I think your #6 copper is fine over 95'.

4-#6 THHN is ok in 3/4" EMT. It might be tough to pull if you have several turns.
Old 02-02-05, 05:54 PM
Join Date: Dec 2004
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Hi flyingtooth I agree with Ron, maximum number of 90 4 keep it less if possible, also # 8 for ground is code where i live, be sure to check your local codes tho.

lol steve
Old 02-02-05, 06:09 PM
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Four #6's in 3/4" Sealtite will be a b*tch. Especially with a 90 connector. For a typical 50 amp hot tub feed I use 1", pvc and sealtite.
Old 02-02-05, 07:15 PM
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You guys are talking to a guy who hasn't even visited this forum in 16 months!
Old 02-02-05, 07:44 PM
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I didn't even notice the OP. I just saw the new post icon.
Man, what a fool.
I wonder if he ever got the #6's through the flex.

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