Surge Arrester Leakage Current Remote Metering at a 500kV Substation in Shandong Province

Project Overview

A 500 kV substation operated by the ultra-high-voltage maintenance company of State Grid Shandong Electric Power applies surge arrester leakage current remote-transmission meters supplied by Zhuhai Huawang Technology Co., Ltd. The customer has issued a stamped product application certificate confirming the use of the meters in service.

Following the company’s policy for public materials, the substation name is omitted in this summary; the stamped certificate can be presented to qualified customers on request.

Why Monitor Surge Arrester Leakage Current

Metal-oxide surge arresters (MOA) protect substations against lightning and switching overvoltages. As an arrester ages, its resistive leakage current gradually increases, which is one of the earliest observable indicators of deterioration.

Meter-type arrester leakage current monitoring instruments are installed in the arrester ground path and display the total leakage current while transmitting readings to a remote system. Continuous records allow maintenance personnel to observe trends rather than single snapshots, which supports condition-based maintenance decisions.

Meter-Type Design for Substation retrofits

The meter-type instruments used in this project are designed for installation in the arrester ground connection and provide:

Local digital display of leakage current for on-site inspection rounds.
Remote transmission of readings so that substation personnel can review data without entering the bay.
A passive, self-powered sensing principle on the meter variant, which avoids battery replacement and reduces maintenance workload.

This makes the meter type suitable both for new substations and for retrofitting existing bays without rewiring the ground circuit.

Scope Boundary

Resistive-current separation techniques differ between meter types and vendors; readings are intended for trend monitoring and cross-checking, and acceptance testing should follow the applicable industry test procedures for surge arresters.

Project Details

Voltage level: 500 kV
Equipment type: Metal-oxide surge arresters (MOA)
Scope: Arrester leakage current remote-transmission metering
Customer type: State Grid ultra-high-voltage operation company (Shandong, China)
Evidence: Customer-stamped product application certificate