Welder extension

[Tractor Seabee]

I found that the least expensive solution to a 50A 4 wire extension cord was a RV extension cord. They come with the molded ends. 320.00 on LOWES web site for the 50'

Ron

 

[Deere Dude]

In my move and not knowing where I wanted to set up my welder I hooked up a plastic sheathed 70-80' 6 gauge 3 copper wire with to my breaker box with 50-60 amp breaker, not sure. The end of the wire has a bakelite connector on it. When I want to weld across the room or down the driveway a stretch I just unwind as much as I want off the hanger.

That wouldn't be as nice as 50 amp extension cords but is hanging on the wall and works for me. No idea of the cost. Maybe a couple hundred.

 

[LD1]

Without looking up that welder......does that welder have sensitive electronics? Or is it a basic transformer machine.

Also keep in mind that you will pull a MAX of 46 amps. So that would be having the welder and the wire feeder cranked to the max.

8 gauge will keep voltage drop under 3%......what you want if it has sensitive electronics. 10 gauge would keep it under 5%.

Would help to know what you are starting with from the power company. My "240v" service is actually 246v coming in to my panel.

Why does it have to be a portable cord? That would be strung across the floor and rolled up every time? If this is the new home for the welder, consider a permanent outlet. 8-2 w/ground for a permanent install is like 65 cents a foot. 8/3 SOOW portable cord is like $2/ft.

 

[Tractor Seabee]

Without looking up that welder......does that welder have sensitive electronics? Or is it a basic transformer machine.

Also keep in mind that you will pull a MAX of 46 amps. So that would be having the welder and the wire feeder cranked to the max.

8 gauge will keep voltage drop under 3%......what you want if it has sensitive electronics. 10 gauge would keep it under 5%.

Would help to know what you are starting with from the power company. My "240v" service is actually 246v coming in to my panel.

Why does it have to be a portable cord? That would be strung across the floor and rolled up every time? If this is the new home for the welder, consider a permanent outlet. 8-2 w/ground for a permanent install is like 65 cents a foot. 8/3 SOOW portable cord is like $2/ft.

LD1, what code book are you looking at? My 225A AC/DC welder has all #6 wire from panel to receptacle and through short SO cord to machine. The SDO cord gets warm with sustained use at 200A DC weld output. Voltage drop is one thing, heat is another with undersized wire and both are related to each other. I would not under sizing just to save a few bucks. Continued heating causes insulation to break down quickly. Even Mark from Everlast states that the manufacturer recommends a #6 50A circuit. That is code compliant.

Ron

 

[LD1]

LD1, what code book are you looking at? My 225A AC/DC welder has all #6 wire from panel to receptacle and through short SO cord to machine. The SDO cord gets warm with sustained use at 200A DC weld output. Voltage drop is one thing, heat is another with undersized wire and both are related to each other. I would not under sizing just to save a few bucks. Continued heating causes insulation to break down quickly. Even Mark from Everlast states that the manufacturer recommends a #6 50A circuit. That is code compliant.

Ron

No code book, just looking at the voltage drop calculations.

There are some special things that come into play if wiring for a dedicated welder. The wire is sometime allowed to be smaller than what would be called for in a circuit for other things, because welding is not continuous duty.

There is never anything wrong with oversizing the wire. I even mentioned using 6ga wire, to keep the voltage drop below 3%. That would be well within requirements for the welder to deliver 46a at the end of a 100' run. Sure, 8ga, if the welder is pushed to the max for the duration of its duty cycle for an extended period of time, the wire will get warmer. But not beyond what the wire should be capable of

 

[Mark @ Everlast]

I suppose everyone is an expert on welder wiring. But most electricians don't know there are separate rules for wiring. Several things.

1) Only breakers are sized based off Max Inrush.
2) Wire size is derated based off of Duty Cycle. Wiring codes that most refer to is for continuous, maximum load.
3) Wire size is based off of the Ieff1 amps, not max inrush. This is called "rated" current. There's a difference. Max inrush regulates breaker sizes. Max effective current is based off of what the unit pulls continuously at maximum operating parameters. This is the amperage that is derated based off of duty cycle.

Article 630 of the NEC governs welders and welding equipment. Most electricians have never read this far into the book or skimmed over it.

 

[Mark @ Everlast]

LD1, what code book are you looking at? My 225A AC/DC welder has all #6 wire from panel to receptacle and through short SO cord to machine. The SDO cord gets warm with sustained use at 200A DC weld output. Voltage drop is one thing, heat is another with undersized wire and both are related to each other. I would not under sizing just to save a few bucks. Continued heating causes insulation to break down quickly. Even Mark from Everlast states that the manufacturer recommends a #6 50A circuit. That is code compliant.

Ron

Is that a Lincoln tombstone? It's only 125A DC.

 

[Sodo]

$.88 per foot for 10/2 SJOOW appx $62.

10/2 Romex is about $.70 /foot. That's $49

I expected the SJOOW to cost a lot more than Romex.

 

[swines]

If you want to go by the NEC, you have to understand the difference between designing a branch circuit (panel to outlet) and an extension cord.

What you really need to take into account is the maximum current draw in Amps, and the welder's duty cycle.

As an example, if you have a welder that draws a maximum of 40A with a duty cycle of 50%, you would use the multiplication factor of .71 (from NEC Table 630.11). The calculated current draw, taking into account the duty cycle, is: 40A x .71 = 28.40A. From Table 310.15(B)(16) - a 10 gage conductor has an ampacity of 35 Amps at 75F.

Therefore, for the imaginary welder drawing 40A with a 50% duty cycle - a 10 gage extension cable would be adequate.

 

[aczlan]

$.88 per foot for 10/2 SJOOW appx $62.

10/2 Romex is about $.70 /foot. That's $49

I expected the SJOOW to cost a lot more than Romex.

Note that you need 10/3 ( 1/3 SJOOW Portable Cord 3V UL/CSA | WireAndCableYourWay.com ), not 10/2. When referencing cord, all conductors are insulated so you have to count all of them.

Aaron Z