Need Purchasing Advice

[Cr2348455]

I have the same machine, a 220V, 210A max Miller Thunderbolt 210. They do come with #4 cables. The #4 cables are just big enough to do the job.

My other “stick welder” (a Miller Dynasty 210DX) has much thicker cables (2/0). I cannot tell the difference when welding with either #4 or 0/2 cables.

Just to be clear, I have a older Miller Dialarc HF, which goes up to 310 amps.
On another post , the majority suggested #1 is
adequate.
At 210 amps, why would you have 2/0 leads ?
I am concerned that my old taped up leads might be 3/0 or even 4/0. I have no way to tell, no visible labels. It welds great at 200 amps and higher, I don’t want to have any problems.

 

[erikmannie]

Just to be clear, I have a older Miller Dialarc HF, which goes up to 310 amps.
On another post , the majority suggested #1 is
adequate.
At 210 amps, why would you have 2/0 leads ?
I am concerned that my old taped up leads might be 3/0 or even 4/0. I have no way to tell, no visible labels. It welds great at 200 amps and higher, I don’t want to have any problems.

I chose that size (2/0) when I was setting up the first real welder that I had ever had. I went online & looked at charts relating to being able to get the full 210A at 50’.

I purposely chose a larger size in order to have very low resistance.

From:

Selecting the Proper Size Welding Cables | Lincoln Electric

When selecting the proper cable size for your welding equipment, it is best to choose cable that can handle the maximum output of the welder.

www.lincolnelectric.com

Edit:
Taking another look at this, it looks like a #4 cable is too small and a 0/2 is too large for 210A. Having stick welded extensively with both, the 0/2 is a hero and the #4 cable is so-so.

 

[Cr2348455]

I chose that size (2/0) when I was setting up the first real welder that I had ever had. I went online & looked at charts relating to being able to get the full 210A at 50’.

I purposely chose a larger size in order to have very low resistance.

From:

Selecting the Proper Size Welding Cables | Lincoln Electric

When selecting the proper cable size for your welding equipment, it is best to choose cable that can handle the maximum output of the welder.

www.lincolnelectric.com

View attachment 364622

Understood
I finally got a section of my old leads and found the size, 1/0 , so I know the size.
I am not that knowledgeable about resistance, perhaps others who have knowledge might advise.

 

[Tim9]

Color: You may want additional insulation colors to distinguish between different cables.

Gauge	Max Amps	Nomnial OD (in.)	Conductor Diameter (in.)	Conductor Stranding
6 AWG	115	0.303	0.2	260/30
4 AWG	150	0.331	0.228	364/30
2 AWG	205	0.413	0.3	624/30
1 AWG	240	0.481	0.343	767/30
1/0	285	0.526	0.373	975/30
2/0	325	0.564	0.426	1196/30
3/0	380	0.621	0.465	1547/30
4/0	440	0.686	0.56	1950/30

since you had a 300 amp welder I just assumed you meant 1/0
1 gauge wire seems woefully inadequate to me. But...Im just a hack. Anyway...whatever size tweeco you want you should be able to get a connector for the size of your wire. Just google it. They probably make them. But they won't be for 300 amps if you have 1 gauge wire. It is what it is.

 

[Tim9]

It’s basically about voltage drop and resistance of wiring. For instance…To properly run a 15 amp 120 volt power saw using a 100 foot extension cord you would want a thicker gauge wiring in that cord. A simple voltage ohm meter hand held meter placed at the plug of the saw cord would show you what happens when turning on your saw.
If you were using a 16 gauge extension cord then I’m guessing that the voltage would drop to @ 108 volts. That’s really hard on the motor. Without getting to sidelined, it’s the voltage drop that kills electric motors. I recently saw a review online of an air compressor in which the reviewer complained about burning up 3 motors on his new compressor. Everyone else loved the compressor. My first thought was that this guy had a serious voltage drop problem in his electrical wiring of his shop.
Anyway, just like that wiring was too small a gauge to drive a 5 hp motor of his compressor because of voltage drop…. Same thing happens for welders. And fwiw, voltage drop and resistance are directly related to Each other. It’s all about OHMS Law.
watts=amps x voltage

But…. I’m not trying to speak Greek to you and overload your brain. Bottom line is follow those charts.
and then check out some voltage drop charts.

voltage drop isn’t really the main thing you need to focus on for your welder. But those welding gauge charts are important. Those charts cut through the complicated stuff. And it gets complicated when we start discussing welding because there’s lower voltage than a motor circuit plus there’s a duty cycle. Anyway… it’s important if you want good welds. No way are your welds going to look good or be good…. If you try to push 300 amps through #1 wire that’s 100’ long. It’s just against the physics of electricity.
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Edit—-wow, I really rattled on there and just noticed you do have 1/0 wire. Then you should be good to go.