Line Drop Produced by Resistance Welders

Resistance-welding machines normally form a very reactive pulsating load on a power system which sometimes produces undesirable line regulation. The regulation can be calculated, and, if it is too high, it can be reduced by operation directly on 2,300 volts or by power-factor-correction means. From a line-regulation point of view, the system of 2,300-volt operation is usually the most satisfactory. The effect of electronic controls on line drop is also discussed.