69kV 600A Single Pole Switch
This switch is used to short insertion resistors on an arc furnace having a 69kV primary voltage. This switch is solenoid operated because to prevent overheating the resistors the resistors must be shorted at 100 milliseconds after being energized. Only the solenoid operated switch has the precision to meet this timing requirement. This switch contains one form A (e.g. normal open) and one form B (e.g. normal closed) auxiliary contact. A control for operating this switch is shown here. The repair parts except for the pull rods and the line-to-ground insulators are the same as for the 34kV switch shown here.