IEEE C37.20.4 – IEEE Standard for Indoor AC Switches (1 kV to 38 kV) for Use in Metal-Enclosed Switchgear
Revision Standard – Active.Indoor ac medium-voltage switches for use in enclosures for application in power circuits at voltages above 1 kV through 38 kV are covered in this standard. Stationary or drawout, manual or power operation, and fused or unfused are included.