I think I undersized my wire

[Poolshark314]

I used 4 AWG copper for my subpanel run which is a little under 200 ft. Can I use a 60 amp breaker to feed my subpanel? I brainfarted thinking I could do over 80 amps with it but forgot about 80% rule or distance, which is okay because I don't plan on having a bunch of high demand equipment running at the same time.

 

[Walkers]

What is the 80% rule? The chart says it is good for the amps, I wouldn’t have any issue with it.

 

[jeepxj]

THHN in conduit? what temp rating on the breaker?

80% rule is for steady loads like an electric heater or car.

 

[Poolshark314]

What is the 80% rule? The chart says it is good for the amps, I wouldn’t have any issue with it.

100 Amp Wire Size: Which AWG Wire For 100 Amps? (NEC Code)

Looking for wire size for 100 amp service? If you are trying to set up a 100 amp conduit circuit, you will need to make sure to choose the right wire size. 100 amp circuit at 240V can handle up to 24,000W of electricity. Power = 100 Amps × 240V = 24,000W In the US, ... Read more

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THHN in conduit? what temp rating on the breaker?

80% rule is for steady loads like an electric heater or car.

Yes THHN in PVC conduit. 75*

 

[mike93lx]

80% has to do with breaker sizing for constant loads, as stated already. It has nothing to do with distance

60 is right where you want to be at 200ft with #4 copper. that breaker is fine. 48a is all that you can have for constant load on it.

What will you be running on this sub?

For a regular, single person shop, you will almost certainly be fine

 

[Poolshark314]

80% has to do with breaker sizing for constant loads, as stated already. It has nothing to do with distance

60 is right where you want to be at 200ft with #4 copper. that breaker is fine. 48a is all that you can have for constant load on it.

What will you be running on this sub?

For a regular, single person shop, you will almost certainly be fine

I have a welder, mini split, and will plan on 4 post lift but they certainly will not all be running at once. Thanks

 

[mike93lx]

I have a welder, mini split, and will plan on 4 post lift but they certainly will not all be running at once. Thanks

60 will be plenty.

Make sure you use a decent sized sub (I'd go at least 20 spaces). The main breaker in that doesn't matter, just make sure it is at least as large as 60.

 

[Poolshark314]

60 will be plenty.

Make sure you use a decent sized sub (I'd go at least 20 spaces). The main breaker in that doesn't matter, just make sure it is at least as large as 60.

Yep it's a 100 amp sub

 

[TractorJeff]

One Guy?
60 is FINE!
This is GJ though, next post will say, "Rip it out to install 2 gauge wire!"
LOL!
I run a Fridge, Window A/C, Ceiling Fan, LED Lights, Radio, the Compressor or Mig occasionally on a "Temp" 10 ga 75 feet!
Waiting for Wire cost to go down to finish that project!
OMG!

 

[larry4406]

Growing up in a family of 6 our whole house was served with 60A! House was built late 50’s.

 

[Toyo72]

Waiting for Wire cost to go down to finish that project!
OMG!

Man I hear you. I'm in the process of getting conduit and wire for my shop. Copper is crazy at the moment.

I do have a similar question to the OP - I'm planning on placing about 11 receptacles along the back and side wall, and the panel is on the front wall opposite side. Total length from the panel to the last receptacle will be 125 feet through conduit, and it will likely be the only wire in the conduit. No welders, just shop fans, grinders, compressor, miter saw, etc, typical work bench type tools. Planning a 20A breaker, should I use 10-AWG THHN stranded or is 12-AWG big enough? I have a spool of 12 gauge... the bigger stuff is quite pricey.

 

[The Cobbler]

Growing up in a family of 6 our whole house was served with 60A! House was built late 50’s.

my family homestead circa 1950 was 35 amps / 4 circuits plus stove . my dad always said he wanted to go to 60 amp but the electrician said , " you'll never need that much " early 80's it was upgraded to 100 amp. the shop I recently built on the same property is 40 amp, I bought an offcut of tek cable that I knew was too short, I made up the 10ish feet shortfall with 8 gauge that I had a pc of , otherwise I would have done 60 amp . I just wanted insoection & figured I would upgrade later , but really, for what I do, 40 is enough

 

[TractorJeff]

Man I hear you. I'm in the process of getting conduit and wire for my shop. Copper is crazy at the moment.

I do have a similar question to the OP - I'm planning on placing about 11 receptacles along the back and side wall, and the panel is on the front wall opposite side. Total length from the panel to the last receptacle will be 125 feet through conduit, and it will likely be the only wire in the conduit. No welders, just shop fans, grinders, compressor, miter saw, etc, typical work bench type tools. Planning a 20A breaker, should I use 10-AWG THHN stranded or is 12-AWG big enough? I have a spool of 12 gauge... the bigger stuff is quite pricey.

I would use the 12ga on a 20amp Breaker if I already had a spool of it.

 

[mike93lx]

Man I hear you. I'm in the process of getting conduit and wire for my shop. Copper is crazy at the moment.

I do have a similar question to the OP - I'm planning on placing about 11 receptacles along the back and side wall, and the panel is on the front wall opposite side. Total length from the panel to the last receptacle will be 125 feet through conduit, and it will likely be the only wire in the conduit. No welders, just shop fans, grinders, compressor, miter saw, etc, typical work bench type tools. Planning a 20A breaker, should I use 10-AWG THHN stranded or is 12-AWG big enough? I have a spool of 12 gauge... the bigger stuff is quite pricey.

If you ever think you will actually need 20a, 12 won't cut it.

Personally I would do a 15a breaker and the 12 or a 20a breaker and 10

 

[Norcal]

Man I hear you. I'm in the process of getting conduit and wire for my shop. Copper is crazy at the moment.

I do have a similar question to the OP - I'm planning on placing about 11 receptacles along the back and side wall, and the panel is on the front wall opposite side. Total length from the panel to the last receptacle will be 125 feet through conduit, and it will likely be the only wire in the conduit. No welders, just shop fans, grinders, compressor, miter saw, etc, typical work bench type tools. Planning a 20Areaker, should I use 10-AWG THHN stranded or is 12-AWG big enough? I have a spool of 12 gauge... the bigger stuff is quite pricey.

One spool of wire is not going to cut it, you need at least 2 colors, and 3 if a grounding conductor is pulled, black, white, green, and red, would not hurt either, the reason one color won't cut it is that reidentifying conductors smaller the 4 AWG is not permitted by the NEC.

 

[Toyo72]

One spool of wire is not going to cut it, you need at least 2 colors, and 3 if a grounding conductor is pulled, black, white, green, and red, would not hurt either, the reason one color won't cut it is that reidentifying conductors smaller the 4 AWG is not permitted by the NEC.

I should have been more specific - I have 500-ft spools in each color, 12-AWG.

 

[Toyo72]

If you ever think you will actually need 20a, 12 won't cut it.

Personally I would do a 15a breaker and the 12 or a 20a breaker and 10

Yeah, that's what I'm thinking.