5.4 Welding Leads
Large diameter, superflexible leads (cables) are used to carry current from the welding machine to the work and back. The lead from the machine to the electrode holder is known as the electrode lead. The lead from the work to the machine is known as the workpiece lead or ground lead. See Figure 5-31.
Leads are well-insulated. They may be insulated with rubber and a woven fabric reinforcing layer, as shown in Figure 5-32A. Leads may be covered with neoprene, as shown in Figure 5-32B. The leads are usually subjected to considerable wear and should be checked periodically for breaks in the insulation. The voltage carried by the leads is not excessive, varying between approximately 14V and 80V.
Leads are well-insulated. They may be insulated with rubber and a woven fabric reinforcing layer, as shown in Figure 5-32A. Leads may be covered with neoprene, as shown in Figure 5-32B. The leads are usually subjected to considerable wear and should be checked periodically for breaks in the insulation. The voltage carried by the leads is not excessive, varying between approximately 14V and 80V.
Leads are produced in several sizes. The smaller the number, the larger the diameter of the lead. Figure 5-33 is a list of sizes and current capacities for copper leads. The lead must be flexible to permit easy installation of the cable, and to reduce the strain on the arc welder's hand when welding. To produce this flexibility, as many as 800 to 2500 fine wires are used in each cable. The same diameter electric cable must be used on both the electrode and workpiece leads. The length of the lead has considerable effect on the size to be used for certain capacity machines. Use short leads to minimize current loss due to the lead resistance. Keep the electrode lead and the ground lead close to each other. This minimizes current reduction due to inductance.
If a motor-driven generator is used, the wiring to the motor must conform to local, state, and national electrical codes. Copper leads are preferred; however, aluminum leads have been used. Aluminum has about 61% the current-carrying capacity of copper. For a given current capacity, an aluminum lead will be larger in diameter, but only about one-half as heavy. Aluminum leads are pure, semi-annealed, electrolytic aluminum.
If a motor-driven generator is used, the wiring to the motor must conform to local, state, and national electrical codes. Copper leads are preferred; however, aluminum leads have been used. Aluminum has about 61% the current-carrying capacity of copper. For a given current capacity, an aluminum lead will be larger in diameter, but only about one-half as heavy. Aluminum leads are pure, semi-annealed, electrolytic aluminum.