Welder Extension Cord

[Travelover]

he could plug that thing into a 115v 15 amp circuit if he wanted to, you can always use a wire thicker then needed, but never thinner. I used to have my welder plugged into a 30 amp circuit, with a 25 foot 4/3 cord, thats way better than the 10/3 needed, much less voltage drop.

I think this is correct. The critical thing is that the fuse blows before the wire glows.

 

[deereman75]

Mine is 8/3 wire. I am assuming in my situation I should be fine. What is your opinion?

I am sure you will be fine. My outdated code book says 8 gauge is for up to 60 amps. I was actually going to get 20 feet of 6 or 8 gauge for my welders cord, but because of a mistake by the new guy at the cable store, we got 25 feet of 4 gauge for like $40-$50. If I had to pay the full price for the cable, no way would I use 4 gauge, 6 at the most. (this thing is HEAVY)

 

[grsthegreat]

I am sure you will be fine. My outdated code book says 8 gauge is for up to 60 amps. I was actually going to get 20 feet of 6 or 8 gauge for my welders cord, but because of a mistake by the new guy at the cable store, we got 25 feet of 4 gauge for like $40-$50. If I had to pay the full price for the cable, no way would I use 4 gauge, 6 at the most. (this thing is HEAVY)

60 amp Canadian is 40 amps US . THHN wire #8 is rated 40 amps @ 60C (140F) which is how they rate extension cords. If you use the 90C tables, it goes to 59 amps, but no one recognizes that temp range for cables.

 

[deereman75]

60 amp Canadian is 40 amps US . THHN wire #8 is rated 40 amps @ 60C (140F) which is how they rate extension cords. If you use the 90C tables, it goes to 59 amps, but no one recognizes that temp range for cables.

I am sure you know far more about this then I do, and I am sure you are right. I was looking at the table some more, and it is for loomex cable, and is based on a spec sheet from 1982. (this isnt the offical code book, just a simplified version, based on the offical version)

 

[grsthegreat]

I am sure you know far more about this then I do, and I am sure you are right. I was looking at the table some more, and it is for loomex cable, and is based on a spec sheet from 1982. (this isnt the offical code book, just a simplified version, based on the offical version)

i wish they would bring back the old 1970's code books . they were like 1/4" thick hehe. My new code book is about 2" thick..all of it useless garbage :laughing: :laughing: :laughing: :laughing: :laughing: :laughing:. Its amazing how the 1950 houses are running just fine thank you

 

[kennyd]

Welder circuits and extension cords can be Derated a little bit due to the duty cycle of welders, meaning they are not drawing current constantly. Your #8 cord is perfect. Just look at the Cord that came attached to the welder, it's probably #10.

 

[J_J]

ToolBoxTavern,

You only have 33 A input current at 208 V with a 40 A cutting ability.

http://www.hobartwelders.com/pdf/spec_sheets/AirForce_700i.pdf

Wire Size Calculator

This calculator says that if using a 50 ft cord, and 33 input amps at 208 V, the wire size required computes at #14, single phase , copper wire.

 

[J_J]

60 amp Canadian is 40 amps US . THHN wire #8 is rated 40 amps @ 60C (140F) which is how they rate extension cords. If you use the 90C tables, it goes to 59 amps, but no one recognizes that temp range for cables.

Please explain how your amps are different.

40 A US, should be 40 A Canadian.

 

[J_J]

Yes, required by code to ground all metal bits, plus a very good idea.

JJ, #8 is used for ~50A circuits, not 80A. This is a standard welder extension cord. I can buy the exact cord with the 50A M&F plug ends on it from Hobart at the Fleet Farm store here. For home use, it is hard to get something that really needs more than 50A, and even harder to drive a welder hard enough to max that out. Home welders just don't run that hot and heavy. Not many interstate bridges built in home garages...

Use this calculator and tell me what it calculates for a 50 ft wire, and 80 amps. Should compute at #8 wire

Wire Size Calculator

This is what Lincoln says, 230VAC Single Phase 70 Amps #8




120V/40A = #10 wire.

208V/40A = #12


Pro Cut-80

K1581-1 98

208/230/460/ 1-ph: 96/87/48A (44.5)

 

[deereman75]

well that calculator is clearly wrong.

 

[J_J]

well that calculator is clearly wrong.

Is this wrong also?

American Wire Gauge table and AWG Electrical Current Load Limits with skin depth frequencies

 

[JB4310]

Well something is odd, I thought it was generaly accepetd 14 gauge wire is good for 15 amp circuits, 12 ga for 20 amp, 10 ga for 30 amp, 8 ga for 40 amp, and 6 ga for 50 amps.

I'm sure these are not exact ratings, but for wiring residential circuits I thought this was the standard ???

JB

 

[J_J]

#8 extension cords

Millerwelds Miller Welding Equipment, Hobart Welders MIG TIG, Welder Supplies, Compressed Gas Cylinders, Safety

 

[eastexan]

Is this wrong also?

American Wire Gauge table and AWG Electrical Current Load Limits with skin depth frequencies

JJ, I've seen that chart before and got a little confused about the "Maximum Amps For Chassis Wiring" and the "Maximum Amps For Power Transmission".

I guess you're saying that the "maximum amps for chassis wiring" would apply to extension cords, since it specs #8 wire as 73amp?

 

[deereman75]

#8 extension cords

Millerwelds Miller Welding Equipment, Hobart Welders MIG TIG, Welder Supplies, Compressed Gas Cylinders, Safety

those 8 gauge cords are rated for 40 amps, not the 80 amps you claim. that second chart you showed was really irrelivant, it has nothing to do with the rated load for cables, as listed in the electrical code.

 

[paulwestski]

In my state if you wire up a 50amp breaker to #8 wire you'll fail inspection.
All of my 50amp extension cords are #6 three conductor with ground.
Just saying.

 

[J_J]

I talked to the a Lincoln rep about the size wire on my Pro Cut-55, and he says and I agree that #8 is the correct wire to use. He also said to use an extension cord of the same wire size as the cord on the plasma cutter. I can also use my Ranger 8 and the Miller 10 KW Gen/welder with the plasma cutter.

Some of you can get away with some things, some of the time, but you can not get away with all things forever.

It's your machine and wire, so use what you have for the time being until you get it right.

There might be a difference whether the wire is 4-single stranded wires in a 1 in/1 1/4 in conduit, as compared to a wrapped set of 4 wires encased in a rubber sheath. [ extension cord ]

 

[J_J]

Yes, required by code to ground all metal bits, plus a very good idea.

JJ, #8 is used for ~50A circuits, not 80A. This is a standard welder extension cord. I can buy the exact cord with the 50A M&F plug ends on it from Hobart at the Fleet Farm store here. For home use, it is hard to get something that really needs more than 50A, and even harder to drive a welder hard enough to max that out. Home welders just don't run that hot and heavy. Not many interstate bridges built in home garages...

#8 is good from 58A up to 89A according to the calculator at 240 V, copper.

 

[grsthegreat]

Please explain how your amps are different.

40 A US, should be 40 A Canadian.

this was just a joke...my sence of humor

 

[deereman75]

I talked to the a Lincoln rep about the size wire on my Pro Cut-55, and he says and I agree that #8 is the correct wire to use. He also said to use an extension cord of the same wire size as the cord on the plasma cutter. I can also use my Ranger 8 and the Miller 10 KW Gen/welder with the plasma cutter.

Some of you can get away with some things, some of the time, but you can not get away with all things forever.

It's your machine and wire, so use what you have for the time being until you get it right.

There might be a difference whether the wire is 4-single stranded wires in a 1 in/1 1/4 in conduit, as compared to a wrapped set of 4 wires encased in a rubber sheath. [ extension cord ]

It is not a case of us getting away with things, we are using a heavier wire then needed, you are using a wire that is just big enough/too small, you are the one who is getting away with something. It is more a case of you using what you have, and not doing it right. With cables for things like this, thicker is better, there is no advantage in in using a wire at its max rating, except cost. The cable for my welder is almost 2x as thick as needed, so I am at much less risk of something going wrong than you are, with a wire being used right at/over its rated load.