CHOOSING THE RIGHT WELDING CABLE Direct Wire’s welding cable ampacity chart intends to support and guide welding professionals toward the proper cable gauge and length. This information is for reference only, and it is highly recommended the user consult a licensed electrical engineer for a particular welding application. For welding applications, using the proper cable gauge size is critical to ensure high-quality welds and protect the user and their welding equipment. Specifications that should be considered when selecting welding cable include: AMPACITY: Welding cable ampacity (also known as current-carrying capacity or current rating) refers to the maximum amount of current (in amperes) that a cable conductor can continuously and safely carry without exceeding the operating temperature rating. LENGTH: Welding cables should be long enough to provide the user with adequate length to reach all work areas—without becoming a hazard. It is essential to keep in mind (1) ampacity ratings decrease as length increases due to additional resistance, and (2) welding cable should be spread apart to allow heat to dissipate during use. GAUGE SIZE: It is critical to select the proper gauge size for the given welding application. A longer, thinner welding cable will carry lower ampacity. If a longer cable is needed, the user should consider thicker gauge sizes. An improper gauge size will not carry the anticipated current, which can cause excessive heat absorption (melting and fire hazard), failure, and damage to equipment. CONSTRUCTION: Welding cable construction uses a multi-stranded single conductor insulated (or jacketed) by a single layer of EPDM or neoprene thermoset with a temperature rating of -50°C (-58°F) to 105°C (221°F). Superior flexibility, durability, and resistance properties are also vital to a welding cable’s ability to perform in a range of demanding applications and environments. STANDARDS & APPROVALS: Welders should look for key industry standards and approvals, ensuring quality and performance while protecting against substandard manufacturing. For welding cable, these may include SAE J1127 (battery), NFPA 70/NEC Article 630, UL 558 and 583 (and others), and CA Prop 65. Direct Wire’s Flex-A-Prene® and Ultra-Flex® premium welding cables meet or exceed the SAE J1127 standard, which requires minimum copper amounts per gauge (i.e., guaranteed copper contents), appropriate sizing for specific applications, and testing for mechanical and performance characteristics. FLEXIBILITY: Fine copper stranding and a high-quality outer insulation/jacket layer provide welding cable with increased flexibility, smoother pulling across various surfaces, and ease-of-movement on the job site. COLOR & MARKINGS: Colored welding cable and customized markings can be used for various applications, including ownership and identification, accurate footage (or sequential) markings, industry standards and approvals, physical and mechanical characteristics, branding, and more. SUGGESTED IN-LINE AMPACITY FOR WELDING CABLE 50'75'100'125'150'175'200'225'250'275'300'325'350' AMPsAWG or MCM 100#4#2#2#1#11/02/02/03/03/03/04/04/0 150#2#2#11/02/03/03/04/04/0250250250350 200#2#12/03/03/04/04/0250350350350350 250#11/03/04/04/0250350350350 300#12/03/04/0250350350350 3501/03/04/0250350350 4002/03/0250350350 4502/04/0250350350 5003/04/0350350 5504/0250350 6004/0250350 NOTE 1: For reference only. Due to variables within welding applications, it is recommended the user consult an electrical engineer for a particular welding application. NOTE 2: Distance from power source (per lead). Download / Print Ampacity Chart