Farewell to Tedious Disconnection of Each Unit! On-site Non-disassembly Measurement for Parallel Capacitors

In modern high-voltage substations and large industrial and mining distribution rooms, reactive power compensation parallel capacitor banks and series reactors are core main equipment for grid voltage regulation and power factor improvement. A conventional 110 kV or 220 kV substation is usually equipped with a large capacitor frame composed of dozens or even hundreds of individual capacitors connected in parallel.

Nevertheless, during traditional preventive tests, maintenance and test teams are confronted with heavy workload and safety risks. The conventional bridge method or standard capacitance meter testing requires disassembly of busbar copper bars or shorting flexible wires for every single unit. Each unit is measured separately before the bolts are reinstalled and tightened one by one.

Heavy workload: Hundreds of bolts are repeatedly disassembled and reassembled; testing in one capacitor room often takes one or two full days. High risk of bushing oil leakage: The State Grid guidelines for preventing high-voltage parallel capacitor accidents explicitly warn that frequent forced disassembly and tightening of capacitor terminals with wrenches may easily cause mechanical shear damage at the root of insulating porcelain bushings, resulting in broken sealing gaskets, oil leakage, and even moisture ingress, breakdown and explosion during subsequent operation.

To address this common industry pain point in on-site testing of high-voltage parallel capacitor banks, Baoding Huazheng Electric Manufacturing Co., Ltd. has launched the HZRG-III Capacitance and Inductance Tester, delivering a safer and faster non-disassembly testing solution for substation sites.

Accurate Capacitance Measurement of Individual Units Without Disconnecting On-site Wires The HZRG-III strictly complies with State Grid technical guidelines that “non-disconnection measurement methods are recommended”: No need to remove connecting bars: While the parallel capacitor bank remains fully connected via the busbar, the actual capacitance of a designated single capacitor in the parallel circuit can be directly measured by voltage output together with a high-precision external clamp current sensor (or built-in three-phase test CT). Greatly reduced personal and equipment risks: Cumbersome bolt removal and high-altitude mechanical work are avoided. The capacitor outlet porcelain bushings are protected from mechanical stress, fundamentally eliminating bushing oil leakage risks caused by disassembly and reassembly. Remarkably improved test efficiency: A full substation capacitor capacitance survey that used to take an entire day can now be completed rapidly. Simply move the test clamps and clips, and continuous screening of one capacitor bank can be finished within minutes.

No bar disassembly, bushing protection, accurate measurement. Featuring intelligent test logic, the HZRG-III provides solid and convenient professional support for periodic maintenance and hidden trouble inspection of grid reactive power compensation equipment.