HIDIAN 海电

Ground Wire Glass Insulator

Ground-wire discs with a fixed spark gap and arc-quenching electrodes, 70 kN and 100 kN.

Failing load
70 and 100 kN
Spark gap
20 mm
Disc diameter
200 mm
Coupling
16C

A ground-wire insulator goes between the overhead earth wire and the tower. In normal operation it keeps the earth wire insulated, so the wire can be used for communication or to cut circulating current; when lightning hits, the gap flashes over and the arc is quenched before the power-frequency follow current can establish.

The disc carries a fixed 20 mm gap and two electrodes. The insulation level is set by the gap, not by the disc diameter, which is why the disc is smaller than a line unit at the same mechanical rating.

Four types are made, at 70 kN and 100 kN, in a suspension and a tension arrangement.

Specifications

Values published for each type.

TypeMechanical failing loadkNDisc diametermmSpacingmmCreepagemmCouplingGap discharge, upper limitkVGap discharge, lower limitkV
U70C7020021021716C303
U70CN7020021021716C308
U100C10020021021716C308
U100CN10020021021716C308

Discharge values are power-frequency across the 20 mm gap. Arc-quenching at 2 500 V recovery voltage and 15 mm gap: 35 A inductive, 20 A capacitive, 10 kA power-frequency for 0.2 s, two operations. The catalogue does not give a unit weight for these types.

Choosing a Type

  • Suspension or Tension

    The disc is the same; the difference is the fitting arrangement, chosen by whether the earth wire runs through a suspension clamp or a tension clamp.

  • Gap Setting

    The gap is fixed at 20 mm at the works. The C and CN types differ in the lower discharge limit, 3 kV and 8 kV.

Every disc is routine-tested before it is packed, and each type is type-tested before it is offered for supply.

Ask about Ground Wire Glass Insulator

Send the type designation, the quantity and the standard the project is working to. We reply with a price and a delivery date.

We usually reply within one working day.