Surge arresters from MV distribution to EHV transmission.

Silicone housed arresters for 11 to 33 kV networks, class Distribution High to IEC 60099-4, rated up to 60 kV with a 10 kA nominal discharge current. Outdoor versions protect pole mounted transformers, cable terminations and line equipment, and indoor versions fit inside MV switchgear.

MV arresters can be supplied with our drop-out fuses as combined assemblies on a common mounting bracket, giving pole mounted transformers and spur lines overcurrent and overvoltage protection in one compact unit, with fewer parts to fit on the cross arm.

Station class arresters for 66 to 500 kV substations, with ratings up to 800 kV, in Station Low, Medium and High classes with 10 or 20 kA nominal discharge currents. Silicone housings are available in two designs, and porcelain housings are available for sites that specify them.

Arresters fitted along overhead lines, alongside the insulators, to divert lightning surges and prevent flashovers, reducing outages without adding shield wires or improving tower earthing. Available as externally gapped line arresters (EGLA), which connect only when lightning sparks over a series air gap, and non gapped line arresters (NGLA), which also limit switching overvoltages.

Surge counters that record the number of discharges, counters that also measure total leakage current, monitoring spark gaps that record the charge of each discharge, and online monitoring systems that track leakage current for trend based health assessment.

Arresters for capacitor banks, static VAR compensators, series compensation and HVDC, AC and DC railway arresters, and arresters designed to act as post insulators.

These arresters protect networks in more than 100 countries, including New Zealand and Australia, from a manufacturer with over 100 years of high voltage experience and some of the lowest failure rates in the industry.

The metal oxide varistor (MOV) blocks set an arrester's protection level and energy capability. Ours come only from leading block makers, and every block is individually tested before it goes into an arrester.

Silicone rubber housings keep their water repellence for the life of the arrester, so pollution and salt cannot form a continuous wet layer. The silicone resists tracking, erosion and UV, is fire retardant and self extinguishing, and weighs far less than porcelain.

A cage of glass fibre rods around the blocks for advanced mechanical duty and line arresters, a gas filled glass fibre tube with pressure relief for the highest mechanical and seismic duty, and a compact filament cage, free of partial discharge, for MV and railway arresters.

If an arrester is overloaded, cage and filament cage designs vent without violent failure and tube designs eject no internal parts, with short circuit ratings up to 80 kA.

Proven in coastal and desert regions, heavily polluted industrial areas, high wind zones and earthquake prone regions, with cantilever strength up to 23,000 N·m in silicone and 35,000 N·m in porcelain.

Every block and arrester is routine tested. The manufacturer's own high voltage laboratory runs full type tests, with lightning impulse, power frequency, high current and long duration impulse testing, weather ageing and climate testing from −40°C to +100°C.