Post insulators for apparatuses and plants in conformance to IEC 273 to the voltage level of 420 kV. In this group of insulators, there is a wide range of products concerning voltage levels, strength and creepage distances. Construction is performed in conformance to IEC -273 and IEC – 815 or according to the customer’s request. Voltage level range is 12-420 kV.
- insulators to 145 kV, with the height of 1500 mm are manufactured out of one piece
- insulators to 170 kV, with the height of 1700 mm are manufactured out of one or two pieces
- insulators 170-245 kV are manufactured out of two pieces
- insulators above 245 kV are manufactured out of three pieces, i.e. more pieces (so that the height of a single insulator does not exceed 1500 mm)
Maximal diameter through the shed is 300 mm, bending strength classes are 2 – 12.5 kN. Insulators are manufactured for all four zones of pollution, which corresponds to the specific creepage distances 16; 20; 25 mm/kV.
Shed parameters are determined in conformance to IEC-815. Manufacturing material is the mass C-120. Assembly is performed using sulphur binder or cement. Flanges are manufactured using malleable cast iron, hot dip galvanised (coat thickness is 85 and 100 microns) or aluminium alloys.
Insulators pass the strict control throughout all production process phases; routine ultrasonic test is performed after the cutting and routine bending test is performed after assembly.