Extension cord for welder

[purplepickup]

I need to be able to move my welder around in my shop so I figured I'd make an extension cord.  
I figure 25 feet will be plenty.  I asked about wire gauge size on another post and enjenjo and
sumner said they use 8-3 wire.  The owners manual has this as an electrical guide:

I'm not an electrical guy so I want to make sure I understand this right.  I've checked welding forums
and I've seen a lot of different information.   The way I read the info above is that I need a maximum
of 30 amp breaker and wire size can be 14 ga up to 67 feet long.  

I used 15 feet of 8 ga wire from the box to the receptacle.  I went shopping for flexible wire for an
extension cord and it gets real expensive for 8 ga.  I've already got 12-3 extension cords that I could
change ends on or I saw 10-3 cord at Menards I think it's for motorhome hookups.  I don't want to take
any chances but if I read the specs from Hobart correctly, I could use 14 ga and meet their requirements.  
Am I missing something?

Also, is it better to just make a 25 foot power cord wired directly into the welder instead of using an
extension cord? It would eliminate a couple of connectors and let me change to a locking connector
or something better than the bulky one that Hobart uses(NEMA 6-50 P & R).

[kb426]

I can't imagine that 14 would work. If you look at an electric dryer cord, look at their size. If you use your welder like I do mine, way over the duty cycle, I'd want at least 10 gauge wire.

[enjenjo]

Yes, the 8-3 is a bit of overkill. for that matter 10-3 is too. The local hardware stocks it at a reasonable price though, so I used it. I have the extension cord hard wired to my welder, but if you leave the plug on, you can use it for other things, like a plasma cutter too.

[MrMopar64]

According to this chart you would need 7ga for 30 amps

http://www.powerstream.com/Wire_Size.htm

MM64  

[purplepickup]

I might add that the 6 ft power cord that came with the machine is 12-3.

[Dave]

I might add that the 6 ft power cord that came with the machine is 12-3.

Id use 10/3 Do you know anyone that wires up shop equipment? Buss drop cable is the cats behind for extensions for welders.. 10/3 buss drop will handle 30 amps as will 10/3 romex.
Dave

[Dave]

I might add that the 6 ft power cord that came with the machine is 12-3.

Id use 10/3 Do you know anyone that wires up shop equipment? Buss drop cable is the cats behind for extensions for welders.. 10/3 buss drop will handle 30 amps as will 10/3 romex.
Dave

ps: I have a square D chart.... I swear by it..

[1FATGMC]

I asked about wire gauge size on another post and enjenjo and
sumner said they use 8-3 wire.

Hey George I lied   .  I went and checked and the cord I'm using on the Mig is 10-3.  I have another one that is 8-3 that I had made up for the 225 amp stick welded I have and got confused.

I wired my 3 main welder outlets in my shop with 8-3 off of the main breaker so that I could use the stick welder or any other larger welder in the future if I needed it.  They are all 40 amp circuits.

I also have a 30 amp circuit that has my Mill and Lathe on it plus I put an outlet off of that circuit on the workbench front for the welder.  I think I've welded at the highest setting on that circuit, not positive, and haven't tripped the breaker.

I think my Miller about the size of yours called for a 30 amp circuit.  Anyway I would for sure recommend going to 10-3 and nothing less even though you might get away with it.  Making sure you have the proper voltage at the machine will ensure a long life for it.

Also if you look at your chart they recommend a minimum of a 25 amp breaker and a 30 amp if it is normal.  For a 30 amp circuit you need 10-3.

Besides just use some of that money you saved on the Hobart and get a cord that you know will work now and in the future.

c ya, Sum

[Crosley.In.AZ]

I used a 10-3 extention for my 30 amp parts washer.......about 60 feet long.  Never had any problem.


keep in mind you are usually not at the maximum amp draw the machine is rated at.

A hard wired wall plug I will over wire the circuit to the next size wire when possible

[river1]

keep in mind you are usually not at the maximum amp draw the machine is rated at.

i believe the elect code allows you to under size the wire for a welder because you are only momentarily at max draw at the start of the weld. the welder needs more current to start the arc, once the welding starts the machine settles out to just the current needed to weld.

that said the input voltage affects the output voltage so if your wire is grossly undersized it will affect the output of your welder. while it only affects the welder at it's top end, it is usually there that you NEED it. in my opinion if you buy a welder that can weld to a certain thickness then short change the welder on wire you are spending dollars to save dimes.

later jim

[purplepickup]

Well, I just got back from Lowes where I bought 30' of real flexible yellow rubber 10-3 cord and a plug.  I'm going to wire the cord directly into the welder.  I didn't see any other need to have the extension cord and won't be buying anything else soon.  If I do need a 230V extension cord it will be easy to convert the 30' power cord into an extension cord.  I think this should work out real good.  

Thanks to everyone for the input.  This isn't an area I was trying to save money but I wanted to make sure I understood what I was about to do.

[Sean]

I just bought a 50 foot, 10g extension cord yesterday. $53.95...

Normally we try to use 25' of cord max, but on this particular Job the closest outlet is about 40ft away. We had been running that Miller MaxStar off a 50ft 14g cord and the cord was getting warm to the touch. The outer case of the Welder was getting warmer than normal too.

With the 10g Cord, the Welder is still running a little warmer than normal, but the Cord stays cool and we seem to have normal power now.

[Mikej]

14 gauge = 15 amp circuit
12           = 20
10           =30
8             =60

If you are using a 30 amp breaker you need the 10/3 cord, if your run amps are close to the 30 amp I would then run the 8 gauge wire.

The cord you bought should be wonderful

[river1]

Well, I just got back from Lowes where I bought 30' of real flexible yellow rubber 10-3 cord and a plug.  I'm going to wire the cord directly into the welder.  I didn't see any other need to have the extension cord and won't be buying anything else soon.  If I do need a 230V extension cord it will be easy to convert the 30' power cord into an extension cord.  I think this should work out real good.  

same cord i bought, tho i made an extension cord out of it.

Thanks to everyone for the input.  This isn't an area I was trying to save money but I wanted to make sure I understood what I was about to do.

i knew you weren't try to save money, just spend it wisely. i'm the same way most of the time.

later jim

[manyolkars]

After I built my shop and before I got it wired, I ran 12/3 romex down the fence over 100 feet and used that for my 225 amp welder or my air compressor, which ever I needed.