Hot tub wiring question
#1
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Thread Starter
Hot tub wiring question
I’ll be wiring a new hot tub: main panel-->conduit under house-->transition to underground conduit outdoors-->disconnect-->underground conduit & flex conduit to tub
- also adding two 120v outdoor outlets at the same time
This is the current plan:
(2) first 120v 12/2 UF wire from 15amp breaker at disconnect, through ¾” rigid conduit then transitioning to flex conduit to a 15amp CGFI outdoor outlet
(3) second 120v 12/2 UF wire from 15amp breaker at disconnect, through ¾” rigid conduit then transitioning to flex conduit to another 15amp CGFI outdoor outlet
Questions:
- also adding two 120v outdoor outlets at the same time
This is the current plan:
- 70 amp breaker at house main panel
- 6 gauge, 4 wire (THHN) from house main panel to disconnect, through 3/4” conduit
- disconnect = 50 amp CGFI breaker with two additional 15amp circuit breakers (this one: https://www.spadepot.com/MW-Spa-GFCI...10588C193.aspx)
- three lines emerging from the disconnect:
(2) first 120v 12/2 UF wire from 15amp breaker at disconnect, through ¾” rigid conduit then transitioning to flex conduit to a 15amp CGFI outdoor outlet
(3) second 120v 12/2 UF wire from 15amp breaker at disconnect, through ¾” rigid conduit then transitioning to flex conduit to another 15amp CGFI outdoor outlet
Questions:
- Any issues with the above specs?
- Is 6 gauge sufficient?
- can I use a 60amp breaker at the house instead of 70?
- Is the 12/2 ok with 15amp breakers?
- Currently the plan is to route both of the 120v outlets from their own breaker in the disconnect box, but I suppose I could wire from a 15a breaker in the disconnect to the first outlet, and connect the second outlet in series from the first…might be better?
- What kind of conduit should I use under the house? Was planning on flex conduit.
#2
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diythis
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#3
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Thread Starter
Thank you.
a) Can I use 60 amp instead, with everything else remaining the same? Or was I correct assuming I needed 70amp at the main panel?
b) If not, and I used #4, I believe I will also need to go to 1" conduit, correct? Or, assuming I can pull the wires (it's nearly a straight shot), can I stick with 3/4"?
c) Alternatively, could I use only one 120v 15amp outlet (rather than 2) in addition to the 50amp/240v and stay with #6?
a) Can I use 60 amp instead, with everything else remaining the same? Or was I correct assuming I needed 70amp at the main panel?
b) If not, and I used #4, I believe I will also need to go to 1" conduit, correct? Or, assuming I can pull the wires (it's nearly a straight shot), can I stick with 3/4"?
c) Alternatively, could I use only one 120v 15amp outlet (rather than 2) in addition to the 50amp/240v and stay with #6?
#4
All of today's panels and breakers are rated 75C and if the #6 conductor after de-rating is still rated 65 amps (75C column) then you can use a 70 amp ocpd as long as the calculated load is not more than 65 amps.
You need to make sure your wire is rated THWN or THWN/THHN.
4 #6's is max in a 3/4" pipe. Will actually be snug.
You could protect the circuit at 60A and just put both new receptacles on a single 20A breaker.
You need to make sure your wire is rated THWN or THWN/THHN.
4 #6's is max in a 3/4" pipe. Will actually be snug.
You could protect the circuit at 60A and just put both new receptacles on a single 20A breaker.
diythis
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#5
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Where in the NEC is it stated that when the next standard size breaker is used that the calculated load is not to exceed the conductor ampacity? I'm not seeing it in 240.4(B).
I know 310.15 sets the ampacity, but it's not clarified in 240.4 when going up in size on the breaker.
I know 310.15 sets the ampacity, but it's not clarified in 240.4 when going up in size on the breaker.
#6
Member
Thread Starter
Thanks, useful idea to use 60amp breaker at the main panel and 50amp (tub) & 20 amp (for the outlets/receptacles) at the disconnect. I think this means I can stick with the #6 gauge 4 wire and the 3/4" pvc conduit, which is also good.
#7
You can save a few dollars on your Midwest 50 amp spa panel, this is the same as you linked to except it's cheaper.
https://www.homedepot.com/p/Midwest-...250P/100686230
Or, you can save even more by using this 50 amp spa panel except this one only has two spaces so the circuit for the outdoor receptacles would have to come from main panel. In this case, I'd enlarge the feeder conduit to 1".
https://www.homedepot.com/p/Square-D...0SPA/205170085
Seems like just a few years ago that the Midwest spa panel was the best buy at only around $70 at both Lowes and Home Depot.
https://www.homedepot.com/p/Midwest-...250P/100686230
Or, you can save even more by using this 50 amp spa panel except this one only has two spaces so the circuit for the outdoor receptacles would have to come from main panel. In this case, I'd enlarge the feeder conduit to 1".
https://www.homedepot.com/p/Square-D...0SPA/205170085
Seems like just a few years ago that the Midwest spa panel was the best buy at only around $70 at both Lowes and Home Depot.
diythis
voted this post useful.
#8
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Thread Starter
Thanks for the tip on the same disconnect for less $ at HD. Can I still use 60amp at main panel (6 gauge, 4 wire still) if i have the 50amp CGFI and two 15amp branches at the disconnect?
#9
Can I still use 60amp at main panel (6 gauge, 4 wire still) if i have the 50amp CGFI and two 15amp branches at the disconnect?
#10
@ joe .... question. Since this is going to a spa panel.... I don't usually reduce the ground size.