Measuring Welding Cable Length and Gauge

What it is

Welding cable is a flexible, finely stranded copper (sometimes aluminum) conductor with a tough jacket. In North America it is sized in AWG, running from small numbers like 6 AWG up through 1/0, 2/0, 3/0 and 4/0 (larger conductors). Elsewhere it is sized by cross-section in square millimeters. The size needed depends on welding current, duty cycle and total circuit length. That sizing comes from the machine maker's or cable maker's tables, not from this sheet.

How to identify

1. Read the jacket print. It usually shows size, conductor material, voltage rating and maker.
2. If the print is gone, strip a short length at a lug and compare the conductor to a known sample, or measure the bundled conductor diameter and compare to the cable maker's data.
3. Check the lugs: they are stamped with the cable size they fit.
4. Measure length with a tape or count the reel's foot marks, if printed.

AWG and metric cross-section

Metric cables are not exact equivalents. Check the cable maker's ratings for the metric size.

Measuring circuit length

• Total circuit length is the electrode lead plus the work lead, measured from machine to work and back.
• Use the total circuit length when reading the maker's cable size table.
• Long circuits increase voltage drop. A cable that is fine at 25 ft may be undersized at 100 ft.

Key points

• A smaller AWG number means a larger cable. 1/0 is larger than 1, and 4/0 is larger than 2/0.
• Welding cable is more flexible than building wire of the same size and has a different jacket. Do not substitute.
• Match lugs and connectors to the cable size and connector series.
• Inspect jackets for cuts and exposed copper before use. Repair or replace damaged lengths.

Common mistakes

• Sizing for only one lead instead of the full circuit.
• Reading 2/0 as smaller than 2.
• Using building wire as a welding lead.
• Choosing a metric cable by "nearest number" without checking its rating.

Governing standards: No single governing standard for selection. Use the welding machine and cable maker's tables; ANSI Z49.1 and 29 CFR 1910.254 for safe use.

Reference only. Verify against the current governing code or standard, the manufacturer's data and the project documents before use. Apps for Distributors disclaims liability arising from reliance on this reference.