The OCK 20-20-4 series insulators are designed for insulating and securing current-carrying parts in electrical apparatuses and distribution devices of power plants and substations operating with alternating current at 20 kV and frequencies up to 100 Hz. They provide reliable insulation within an ambient temperature range from -60 °C to +50 °C and comply with the climatic category UHL1 according to GOST 15150.

Technical Specifications:

• Rated Voltage: 20 kV
• Rated Bending Breaking Strength: 20 kN
• Rated Torsional Breaking Moment: 2.0 kN·m
• Structural Height (H): 355 mm
• Insulation Height (L): 250 mm
• Creepage Distance: at least 840 mm
• Withstand Voltage of Lightning Impulse: 130 kV
• Withstand Voltage at Industrial Frequency in Dry Conditions: 80 kV
• Withstand Voltage at Industrial Frequency under Rain: 50 kV
• Flashover Voltage under Pollution and Moisture: at least 26 kV
• Rated Surface Conductivity of Pollution Layer: 30 μS/cm
• Permissible Pollution Degree according to GOST 9920: IV

Mounting Dimensions:

• Height (H): 355 mm
• Top Flange: Ø140 mm, 4 holes M12
• Bottom Flange: Ø140 mm, 4 holes Ø13 mm

The insulators are manufactured according to TU 3494-024-82442590-2015 and comply with GOST R 52082.