To avoid these ads, REGISTER NOW!

Double Check my power needs for Mill and Lathe

Disney

Well-known member
Joined
Dec 20, 2010
Messages
304
Location
Murfreesboro, TN
I just picked up a Bridgeport 2hp mill. I'll be powering it off my shop 220v and a VFD to convert the 220v 1ph to 220v 3ph power. I am also moving my lathe (220v 2hp 1ph) over to where the mill is living, which is on the opposite side of the shop. So I'll need to run a new circuit over to that area. It will be 50' across the shop from where the breaker panel is now. I'm figuring i'll run a line(s) 8's up the wall, 8' down the other side, and it will go back 10' as well. Along with the 50' span i'm looking at 76' +- of power to run. My google-Fu tells me I should probably be running 6ga copper for that. A couple of questions I want cleared up though.

1. Should I make one run over to the area where the mill and lathe will be and put in a small sub panel there and break out a line to each machine from there? Or, should I make two separate runs, one for the mill, one for the lathe.
2. Is my assumption that 6ga wire is enough to handle the loads from these machines? The machines will be running independently as there's only me in here, nobody around that could be running the other machine at the same time.
3. What am I not considering in all of this? I'm not an electrician so i'm sure it's possible i'm missing something.

4. I would also like to run a new 110v line over there as well. I have some 110v wall outlets already in that area, but i'm also going to move my drill press and bandsaw over there and to me it would make sense to give them their own line. I'm ASSuming I would need to run a new line and I couldn't or shouldn't be using one of the legs for the Mill or lathe along with a neutral from the box.
 
To avoid these ads, REGISTER NOW!

TractorJeff

Well-known member
Joined
Dec 8, 2013
Messages
3,309
Location
Elkhorn, WI
If it was me, I would run a sub-Panel over there to draw the 240v for the machines and the dedicated 120v outlets for the other machines.
PS:
There will probably be 5 Posts complaining the you said 220v not 240v and 110v not 120v!
Of course, you could be on the old Tennessee Hydro-Electric system and "may" actually have 220v.
LOL!
 

Jim greengo

Well-known member
Joined
Sep 3, 2018
Messages
7,415
Location
Behind my house
If it was me, I would run a sub-Panel over there to draw the 240v for the machines and the dedicated 120v outlets for the other machines.
PS:
There will probably be 5 Posts complaining the you said 220v not 240v and 110v not 120v!
Of course, you could be on the old Tennessee Hydro-Electric system and "may" actually have 220v.
LOL!
:beer::beer::beer::beer:
 
OP
D

Disney

Well-known member
Joined
Dec 20, 2010
Messages
304
Location
Murfreesboro, TN
2 hp on 240v 1ph is only 12 amps. Where are you coming up with #6?

Just a google search for Distance and voltage. The chart I saw did not have a breakout for amperage.

Since you mentioned it, I looked again and found a page with amp requirements. If I put in 20amp It tells me 12ga.
 
OP
D

Disney

Well-known member
Joined
Dec 20, 2010
Messages
304
Location
Murfreesboro, TN
If it was me, I would run a sub-Panel over there to draw the 240v for the machines and the dedicated 120v outlets for the other machines.
PS:
There will probably be 5 Posts complaining the you said 220v not 240v and 110v not 120v!
Of course, you could be on the old Tennessee Hydro-Electric system and "may" actually have 220v.
LOL!

So run a line with 240v+neutral+Ground over to a sub panel and break everything out from there? I like that idea!

Any opinion as to wire size?
 

wyliesdiesels

Well-known member
Joined
Aug 14, 2012
Messages
20,256
Location
Modesto, CA
Just a google search for Distance and voltage. The chart I saw did not have a breakout for amperage.

Since you mentioned it, I looked again and found a page with amp requirements. If I put in 20amp It tells me 12ga.

thats not how this works.

wire for motor circuits is sized by the motor HP and the corresponding FLC in the NEC table found at 430.248 (for single phase). the corresponding FLC is multiplied by 125%. wire is sized by the result

a 2HP motor needs 15a rated wire, not factoring VD. At 50', #12 should be fine.

But i would put in a subpanel near the machines, then run individual circuits from there.

TABLE+430.248.JPG
 
OP
D

Disney

Well-known member
Joined
Dec 20, 2010
Messages
304
Location
Murfreesboro, TN
thats not how this works.

wire for motor circuits is sized by the motor HP and the corresponding FLC in the NEC table found at 430.248 (for single phase). the corresponding FLC is multiplied by 125%. wire is sized by the result

a 2HP motor needs 15a rated wire, not factoring VD. At 50', #12 should be fine.

But i would put in a subpanel near the machines, then run individual circuits from there.

TABLE+430.248.JPG
Thank you! That is very helpful! I'll grab a 100' roll of 12/3 MC and a sub panel and get to work.
 
To avoid these ads, REGISTER NOW!

Bert_

Well-known member
Joined
Dec 24, 2016
Messages
9,918
Location
NW Iowa
Honestly it sounds like a single run of 12-2 with a couple 240v outlets would be fine. You said it yourself you can't run both machines at the same time. No reason not to put them on the same wire.
 

nadogail

Well-known member
Joined
Jan 23, 2009
Messages
32,351
Location
Coronado, CA
Honestly it sounds like a single run of 12-2 with a couple 240v outlets would be fine. You said it yourself you can't run both machines at the same time. No reason not to put them on the same wire.

I agree with Bert, two machines can be powered by the same circuit because only one will be running at any given time.

IMHO, two people can share the same toilet if they don't both want to sit on it at the same time.
 

Jim greengo

Well-known member
Joined
Sep 3, 2018
Messages
7,415
Location
Behind my house
I agree with Bert, two machines can be powered by the same circuit because only one will be running at any given time.

IMHO, two people can share the same toilet if they don't both want to sit on it at the same time.

I like the same toilet part of the story!:spit::spit::spit:
 
OP
D

Disney

Well-known member
Joined
Dec 20, 2010
Messages
304
Location
Murfreesboro, TN
I thought everything was 110V over there... you have 220V single phase in the USA?!

Almost every house in the USA has 2 hot legs coming in. Depending on where you line they can be anywhere from 110v-125v. Common socket chewing dummies like myself usually say 110v for some reason. My house is actually 246v across the two legs, but I still say 220v. Nom nom not nom......11mm socket my favorite nom nom nom nom
 

Bert_

Well-known member
Joined
Dec 24, 2016
Messages
9,918
Location
NW Iowa
I thought everything was 110V over there... you have 220V single phase in the USA?!

Residential and some light commercial is going to be 120/240 single phase. It's 240v with a center tap.

Anything else is getting 3 phase. You're most common voltages will be 208Y120 or 480Y277. There is still a lot of 240D120 3 phase around but some utilities won't supply it for new install.

Not sure if there's any 600V 3 phase in the states or not. My understanding is that's a common industrial voltage in Canada
 
To avoid these ads, REGISTER NOW!
Top Bottom