Free Expert Guides on Power Systems, Circuit Design & Electrical Troubleshooting

1. Maintaining and Restoring the Factory Insulation ConditionWhen a transformer undergoes factory acceptance tests, its insulation condition is at its optimal state. Thereafter, the insulation condition tends to deteriorate, and the installation phase may be a critical period for sudden degradation. In extreme cases, the dielectric strength may drop to the point of failure, leading to coil burnout immediately upon energization. Under normal circumstances, poor installation quality leaves behind

1. Introduction SF6 electrical equipment, renowned for its excellent arc-quenching and insulating properties, has been widely applied in power systems. To ensure safe operation, real-time monitoring of SF6 gas density is essential. Currently, mechanical pointer-type density relays are commonly used, providing functions such as alarm, lockout, and on-site display. To enhance vibration resistance, most of these relays are filled internally with silicone oil.However, oil leakage from density relays

The 110kV substation at our plant was constructed and put into operation in February 2005. The 110kV system employs ZF4-126\1250-31.5 type SF6 GIS (Gas-Insulated Switchgear) from Beijing Switchgear Factory, comprising seven bays and 29 SF6 gas compartments, including five circuit breaker compartments. Each circuit breaker compartment is equipped with an SF6 gas density relay. Our plant uses the MTK-1 model oil-filled density relays manufactured by Shanghai Xinyuan Instrument Factory. These relay

Leakage in Hydraulic Operating MechanismsFor hydraulic mechanisms, leakage can cause short-term frequent pump starting or excessively long re-pressurization time. Severe internal oil seepage in valves may lead to pressure loss failure. If hydraulic oil enters the nitrogen side of the accumulator cylinder, it can cause abnormal pressure rise, which affects the safe operation of SF6 circuit breakers.Apart from failures caused by damaged or abnormal pressure detection devices and pressure component

1. BackgroundSF6 electrical equipment has been widely applied in power utilities and industrial enterprises, significantly advancing the development of the power industry. Ensuring the reliable and safe operation of SF6 equipment has become a critical task for power departments.The arc-quenching and insulating medium in SF6 equipment is SF6 gas, which must remain sealed—any leakage compromises the reliability and safety of the equipment. Therefore, monitoring the SF6 gas density is essential.Cur

1.SF6 Electrical Equipment and the Common Problem of Oil Leakage in SF6 Density RelaysSF6 electrical equipment is now widely used in power utilities and industrial enterprises, significantly advancing the development of the power industry. The arc-quenching and insulating medium in such equipment is sulfur hexafluoride (SF6) gas, which must not leak. Any leakage compromises the reliable and safe operation of the equipment, making it essential to monitor the SF6 gas density. Currently, mechanical