Product Overview
The HY10WZ-108/281 metal-oxide surge arrester is a polymer-housed gapless metal-oxide surge arrester for 110 kV AC power systems. It is mainly installed on the distribution equipment and station equipment in substations to limit lightning and switching overvoltages and to protect the insulation of electrical equipment such as transformers, circuit breakers, instrument transformers and cables. The HY10WZ-108/281 metal-oxide surge arrester is widely used for overvoltage protection in 110 kV substations.
The product uses high-performance zinc-oxide varistors and a one-piece injection-moulded silicone-rubber composite insulating housing with no series gap; it features good V-I characteristics, large current-carrying capacity, fast response and strong pollution resistance, and can operate stably for a long time in harsh environments such as high altitude, heavy pollution and severe cold.
Type Designation
In HY10WZ-108/281: H denotes surge arrester, Y denotes zinc-oxide varistor; 10 denotes a nominal discharge current of 10 kA; W denotes gapless; Z denotes station type; 108 is the rated voltage of the arrester (kV); 281 is the residual voltage at the nominal discharge current (kV).
Product Features
- ◆ Gapless structure with no follow current and no discharge delay, giving stable protective performance;
- ◆ Composite silicone-rubber housing with UV resistance, ageing resistance and strong anti-pollution-flashover capability;
- ◆ Zinc-oxide varistors with large current-carrying capacity and strong 2 ms rectangular-wave withstand capability;
- ◆ Good sealing performance with little maintenance during long-term operation;
- ◆ Small size, light weight and convenient installation.
Main Technical Parameters
| Item | Value |
|---|---|
| Nominal system voltage | 110 kV |
| Rated voltage of arrester Ur | 108 kV |
| Continuous operating voltage Uc | 84 kV |
| Nominal discharge current | 10 kA |
| Lightning impulse residual voltage (10 kA, 8/20μs） | ≤281 kV |
| DC reference voltage (1 mA) | ≥158 kV |
| 2ms Rectangular-wave current carrying capacity | 1000 A |
| 4/10μs High-current impulse withstand | 100 kA |
| Creepage distance ratio | ≥25 mm/kV |
Service Conditions
- ◆ Ambient temperature: -40 ℃ to +40 ℃;
- ◆ Altitude: ≤2000 m (special design available above this);
- ◆ Wind speed: ≤35 m/s;
- ◆ Ice thickness: ≤10 mm;
- ◆ Seismic intensity: ≤degree 8;
- ◆ Applicable to AC 50 Hz systems; the installation site shall be free from heavy pollution, chemical corrosion and violent vibration.
V-I characteristic curve of the metal-oxide surge arrester
The metal-oxide varistor has non-linear V-I characteristics: the leakage current is extremely small at the normal operating voltage; when an overvoltage occurs it conducts and discharges the energy to earth, and after the overvoltage disappears it automatically returns to the high-resistance state. The figure below shows its typical V-I characteristic curve.
Illustration of the arrester type designation
The arrester type designation consists of codes for the construction type, nominal discharge current, rated voltage, residual voltage and place of use; the figure below gives a visual explanation of each segment.
Product series and outline dimensions of HV metal-oxide surge arresters
The figure below shows the outline structure and main dimensions of the HV metal-oxide surge arrester series (including 110 kV / 220 kV station type and 35 kV line type) for reference in installation layout and clearance verification.
Related Products
Metal-oxide surge arresters of the same series and other types available for selection:
