What I was planning on doing is putting a 20 amp 220 breaker in the panel. Then run 12/2 romex to the 30 amp fused disconnect. Put 20 amp fuses in the disconnect. Color code the white wire to red using red tape. I don't believe a neutral is needed. Just the 2 hot wires and ground. Sound about right?
Question for the electricians
- Thread starter MNBobcat
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jaxs
Elite Member
Work's for me. For what it's worth,the 20 amp breaker at breaker panel will protect everything and meet code regardless what's in the disconnect. It isn't necessary to discard 30 amp fuses and buy 20 amps to replace them. Doesn't hurt either.
RNeumann
Elite Member
Technically yes- USA 220v split phase doesn't need a neutral.
Taping the white wire with red tape on both ends is common practice. However it sounds like you are going to be putting romex in conduit and have the romex in an exterior location. Both no-nos. The wire in conduit should, per code, be rated for such use. If you do this you will have the correct coloring as well.
The Romex for the majority of the run won't be in conduit. I do have a 1 1/2" PVC chase pipe run from the basement to the attic and I'll run the romex through that to the attic and then drill down through the top plate and fish the wire down the wall to the disconnect box.
My understanding is that romex can't be run in conduit in any location that could be wet but that indoors is okay as long as the conduit is sized correctly?
jaxs - The 30 amp fused disconnect didn't come with the fuses so I have to buy them anyway, Otherwise, I'd have used 30 amp fuses and a 20 amp breaker.
My understanding is that romex can't be run in conduit in any location that could be wet but that indoors is okay as long as the conduit is sized correctly?
jaxs - The 30 amp fused disconnect didn't come with the fuses so I have to buy them anyway, Otherwise, I'd have used 30 amp fuses and a 20 amp breaker.
RNeumann
Elite Member
Code does provide for protection of the Romex (NM cable) in conduit in dry locations. So the indoor conduit is close to code....technically it would need to be for the protection of the wire. So basically that part is ok.
My comment was in relation to the exterior wire and conduit. Both rigid and flexible.
GregbkH
Gold Member
The 30 amp disconnect is rated for a max. of 30 amps. It is OK to use 20 fuses in it for a 20 amp circuit.
I ran a 20 amp 240 volt circuit for my mini-split. I used 10-3 w/ground romex on the inside because the run was getting long (voltage drop). When I went to the outside of the building I installed a splice box and spliced 12 awg thwn wires to the 10 awg romex for the final 8 feet to the disconnect. I ran a neutral and capped it off (wire nut) in the disconnect enclosure in case of future need.
Anytime a raceway is installed for electrical it must be rated for electrical. Meaning you can't use pvc water pipe etc. You must use an electrical raceway.
Master electrician.
I ran a 20 amp 240 volt circuit for my mini-split. I used 10-3 w/ground romex on the inside because the run was getting long (voltage drop). When I went to the outside of the building I installed a splice box and spliced 12 awg thwn wires to the 10 awg romex for the final 8 feet to the disconnect. I ran a neutral and capped it off (wire nut) in the disconnect enclosure in case of future need.
Anytime a raceway is installed for electrical it must be rated for electrical. Meaning you can't use pvc water pipe etc. You must use an electrical raceway.
Master electrician.
Hi Greg,
I was thinking about going 10 gauge for the same reason. I was going to measure the run today and then check the voltage drop charts and see if I needed to up-size. I never run 14 gauge wire for anything because 12 gauge isn't much more expensive and it gives me options if I ever need the ampacity. So I have a lot of 12 gauge on hand. 10 gauge I'd have to run to Menards and get. The compressor only needs a little over 14 amps. I'll probably end up using 10 gauge like you, just because I always over engineer everything.
Originally the run was only going to be about 30 feet from the panel. But I can't get access to pull the line because the basement is finished. The area where I thought I had access isn't going to work. Also, I want to mount the panel high enough to be clear of snow so going to the attic and then fishing a line through the stud cavity to the outside wall location will give me the best mounting option.
The PVC chases (I installed 3 when I remodeled the kitchen) were put in place a few years back when I had the walls open so that if in the future I ever needed to run something from the basement to the attic I had an easy way to do it.
I was thinking about it this morning and it came to me that I have an alternative path to the attic. I installed a bathroom on the second floor and I have not yet boxed in and sheet rocked where I ran the drain for the toilet between floors. I already have a couple of electrical lines (GFCI breakers) ran next to the drain pipe for a whirlpool tub I'm installing in a bedroom. So right now it will be easy to run the wire for the A/C using that path and I can save the PVC chases for something else down the road.
The 30 amp disconnect comes with a 4 foot whip to connect from the panel to the compressor. I didn't look to see if the wire was included in the whip. But I have spools of 12 gauge THHN and I'll use that if I need to. I wired about 30 fluorescent lights in my pole building, all through electrical conduit screwed to the metal ceiling, so I have a lot of THHN left over.
Thanks for the info on the fuses. I assumed that it would be fine but I always double check everything because I don't like mistakes so I thought it best to ask.
I was thinking about going 10 gauge for the same reason. I was going to measure the run today and then check the voltage drop charts and see if I needed to up-size. I never run 14 gauge wire for anything because 12 gauge isn't much more expensive and it gives me options if I ever need the ampacity. So I have a lot of 12 gauge on hand. 10 gauge I'd have to run to Menards and get. The compressor only needs a little over 14 amps. I'll probably end up using 10 gauge like you, just because I always over engineer everything.
Originally the run was only going to be about 30 feet from the panel. But I can't get access to pull the line because the basement is finished. The area where I thought I had access isn't going to work. Also, I want to mount the panel high enough to be clear of snow so going to the attic and then fishing a line through the stud cavity to the outside wall location will give me the best mounting option.
The PVC chases (I installed 3 when I remodeled the kitchen) were put in place a few years back when I had the walls open so that if in the future I ever needed to run something from the basement to the attic I had an easy way to do it.
I was thinking about it this morning and it came to me that I have an alternative path to the attic. I installed a bathroom on the second floor and I have not yet boxed in and sheet rocked where I ran the drain for the toilet between floors. I already have a couple of electrical lines (GFCI breakers) ran next to the drain pipe for a whirlpool tub I'm installing in a bedroom. So right now it will be easy to run the wire for the A/C using that path and I can save the PVC chases for something else down the road.
The 30 amp disconnect comes with a 4 foot whip to connect from the panel to the compressor. I didn't look to see if the wire was included in the whip. But I have spools of 12 gauge THHN and I'll use that if I need to. I wired about 30 fluorescent lights in my pole building, all through electrical conduit screwed to the metal ceiling, so I have a lot of THHN left over.
Thanks for the info on the fuses. I assumed that it would be fine but I always double check everything because I don't like mistakes so I thought it best to ask.
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