Electrical contacts for tap changers or stepping switches - using silver deposits on all moving and stationary contact surfaces

摘要

The glide or contact surfaces on the collector ring, or the knife contacts, and on the bridge, are coated with silver, is not 1 mm thick. The silver deposits on the bridge pref. have a different hardness and/or structure to the other Ag deposits. The Ag may be applied by soldering, ultrasonic welding, or deposition welding. Used on switches where the contact bridges are not operated very frequently and the thickness of the Ag can be limited to reduce costs when only a few 100,000 switch cycles are involved. The Ag-Ag contact can carry higher currents than Ag-Cu contacts.