These devices are designed for applying on to 1150 kV overhead lines wires of commercial frequency for separate earthing of wires with 90 to 600 mm² cross-section area of disconnected overhead lines in order to protect personnel in case of accidental energization of the section or appearance of induced voltage in the section. Permissible operating temperature is from –25 ^оC to +55 ^оC at air relative humidity up to 80% at 25 ^оC.