| Operation/Process | Electrode Size in. (mm) | Arc Current (Amperes) | Minimum Protective Shade | Suggested* Shade No. (Comfort) | |
| Shielded metal arc welding (SMAW) | Less than 3/32 (2.5) | Less than 60 | 7 | — | |
| 3/32−5/32 (2.5−4) | 60−160 | 8 | 10 | ||
| 5/32−1/4 (4−6.4) | 160−250 | 10 | 12 | ||
| More than 1/4 (6.4) | 250−550 | 11 | 14 | ||
| Gas metal arc | Less than 60 | 7 | — | ||
| welding (GMAW) and | 60−160 | 10 | 11 | ||
| flux cored arc | 160−250 | 10 | 12 | ||
| welding (FCAW) | 250−550 | 10 | 14 | ||
| Gas tungsten arc | Less than 50 | 8 | 10 | ||
| welding (GTAW) | 50−150 | 8 | 12 | ||
| 150−500 | 10 | 14 | |||
| Air carbon arc cutting | (Light) | Less than 500 500−1000 |
10 | 12 | |
| (CAC−A) | (Heavy) | 11 | 14 | ||
| Plasma arc welding | Less than 20 | 6 | 6 to 8 | ||
| (PAW) | 20−100 | 8 | 10 | ||
| 100−400 | 10 | 12 | |||
| 400−800 | 11 | 14 | |||
| Plasma arc cutting | Less than 20 | 4 | 4 | ||
| (PAC) | 20−40 | 5 | 5 | ||
| 40−60 | 6 | 6 | |||
| 60−80 | 8 | 8 | |||
| 80−300 | 8 | 9 | |||
| 300−400 | 9 | 12 | |||
| 400−800 | 10 | 14 | |||
| Torch brazing (TB) | — | — | 3 or 4 | ||
| Torch soldering (TS) | — | — | 2 | ||
| Carbon arc welding | — | — | 14 | ||
| (CAW) | |||||
| Plate thickness | |||||
| in. | mm | ||||
| Oxyfuel gas welding (OFW) | |||||
| Light | Under 1/8 | Under 3.2 | 4 or 5 | ||
| Medium | 1/8 to 1/2 | 3.2 to 12.7 | 5 or 6 | ||
| Heavy | Over 1/2 | Over 12.7 | 6 or 8 | ||
| Oxygen Cutting (OC) | |||||
| Light | Under 1 | Under 25 | 3 or 4 | ||
| Medium | 1 to 6 | 25 to 150 | 4 or 5 | ||
| Heavy | Over 6 | Over 150 | 5 or 6 | ||
As a rule of thumb, start with a shade that is too dark to see the weld or cut zone. Then go to a lighter shade which gives sufficient view of the weld or cut zone without going below the minimum. In oxyfuel gas welding, cutting, or brazing where the torch produces a high yellow light, it is desirable to use a filter lens that absorbs the yellow or sodium line in the visible light of the (spectrum) operation.
Guide adapted from ANSI Z49.1, 1999.
Low Current Plasma arc cutting data (0−80 Amperes) supplied by Miller Electric Mfg. Co.
Weld Cable Selector Guide*
| Welding Amperes |
Weld Cable Size** And Total Cable (Copper) Length In Weld Circuit Not Exceeding*** |
|||
| 100 ft (30 m) Or Less | 150 ft (45 m) |
200 ft (60 m) |
||
| 10 − 60% Duty Cycle |
60 − 100% Duty Cycle | 10 − 100% Duty Cycle | ||
| 100 | 4 | 4 | 4 | 3 |
| 150 | 3 | 3 | 2 | 1 |
| 200 | 3 | 2 | 1 | 1/0 |
| 250 | 2 | 1 | 1/0 | 2/0 |
| 300 | 1 | 1/0 | 2/0 | 3/0 |
| 350 | 1/0 | 2/0 | 3/0 | 4/0 |
| 400 | 1/0 | 2/0 | 3/0 | 4/0 |
| 500 | 2/0 | 3/0 | 4/0 | 2 ea. 2/0 |
| 600 | 3/0 | 4/0 | 2 ea. 2/0 | 2 ea. 3/0 |
| 700 | 4/0 | 2 ea. 2/0 | 2 ea. 3/0 | 2 ea. 4/0 |
| 800 | 4/0 | 2 ea. 2/0 | 2 ea. 3/0 | 2 ea. 4/0 |
| 900 | 2 ea. 2/0 | 2 ea. 3/0 | 2 ea. 4/0 | 3 ea. 3/0 |
| 1000 | 2 ea. 2/0 | 2 ea. 3/0 | 2 ea. 4/0 | 3 ea. 3/0 |
| 1250 | 2 ea. 3/0 | 2 ea. 4/0 | 3 ea. 3/0 | 4 ea. 3/0 |
*This chart is a general guideline and may not suit all applications. If cable overheating occurs (normally you can smell it), use next size larger cable.
**Weld cable size (AWG) is based on either a 4 volts or less drop or a current density of at least 300 circular mils per ampere. Contact your distributor for the mm2 equivalent weld cable sizes.
***For distances longer than those shown in this Guide, call a factory applications representative.
The above information furnished by: Miller Electric Company www.millerwelds.com and Hobart Electric Company www.hobartwelders.com