The high-voltage switch inspection equipment is a professional instrument used in the power system to conduct state assessment, fault diagnosis, and performance testing of key equipment such as high-voltage circuit breakers, disconnectors, and load switches. It plays a crucial role in ensuring the safe and stable operation of the power grid, preventing equipment accidents, and promoting the implementation of condition-based maintenance.
The following provides a detailed introduction to the high-voltage switch inspection equipment from the perspective of core detection equipment classification and functional dimensions.
I. Core Detection Equipment Classification and Function
1. Mechanical Characteristic Tester
Function: As the most basic and widely used testing equipment in the field of high-voltage switch inspection, it is mainly used to measure the core mechanical parameters of the switch during the opening and closing process, such as time, speed, travel, synchronization, bounce, and rebound.
Key Parameters
Time Characteristics: Opening time, closing time, three-phase synchronization, break synchronization.
Speed and Travel: Initial opening speed, initial closing speed, opening distance, overtravel, total travel curve.
Coil Current: Record the action current waveforms of the opening coil and closing coil to determine the working condition of the electromagnet and whether there are any jamming problems in the equipment.
Application: Through the test data, determine whether the operating state of the operating mechanism (spring, hydraulic, pneumatic type) is normal, and promptly detect potential faults such as mechanical jamming, poor performance of the buffer device, and fatigue of the spring.
2. Circuit Resistance Tester (Microohmmeter)
Function: Using the direct current drop method (the test current is usually no less than 100A), it accurately measures the contact resistance at the contact parts of the switch.
Importance: Excessive contact resistance is the main cause of equipment overheating and even burning. By testing with this equipment, problems such as oxidation, wear, insufficient pressure, or poor contact can be effectively detected.
Standard: The obtained resistance value should be compared with the factory value or historical test data, and the change should generally not exceed 20%.
3. Insulation Characteristic Testing Equipment
Insulation characteristic testing equipment is mainly divided into dielectric strength testing equipment and insulation condition diagnosis equipment. Specifically:
Dielectric Strength Testing
Power Frequency Withstand Voltage Tester: The core function is to test the insulation strength between the main insulation of the high-voltage switch and ground, and at the break.
Impact Voltage Generator: Used to conduct lightning impact tests and operation impact tests to evaluate the equipment’s ability to withstand overvoltage.
Insulation Condition Diagnosis
Insulation Resistance Tester (Megohmmeter): By measuring the insulation resistance, it preliminarily determines whether the equipment insulation is affected by moisture or dirt.
DC High Voltage Generator: Conducts leakage current tests, which can more sensitively reflect potential defects in the equipment’s insulation than the megohmmeter.
Dielectric Loss Factor (tanδ) Tester: For high-voltage switches with SF₆ gas insulation or oil insulation, it measures the dielectric loss factor to effectively assess the deterioration degree of insulation.
4. SF₆ Gas Detection and Treatment Equipment
SF₆ Gas Leak Detector: Has the function of qualitative or quantitative detection of gas chamber sealingness, and can promptly detect gas leakage hazards.
SF₆ Moisture Tester (Dew Point Meter): Precisely measures the moisture content of SF₆ gas. If the moisture content is too high, it will lead to a decline in equipment insulation performance and accelerate the corrosion of the equipment by arc decomposition products.
SF₆ Purity Analyzer: Detects the purity of SF₆ gas. If there is excessive impurity in the gas, it will seriously affect the insulation performance and arc extinguishing ability of the equipment.
SF₆ Gas Recovery / Purification / Charging and Discharging Device: Mainly used for gas recovery, purification treatment, and recharging operations during the maintenance of high-voltage switch equipment.
5. Vibration Acoustic Detection and Partial Discharge Detection Equipment
Vibration Analyzer: By attaching sensors to the surface of the mechanism box, it records the vibration waveforms during the opening and closing process of the switch. Based on the characteristics of the vibration waveforms and the time of peak occurrence, it can accurately reflect the mechanical operating state of the equipment, and is currently an advanced means of equipment fault diagnosis. Ultrasonic / Ultra-High Frequency (UHF) Partial Discharge Detector: Supports online or live detection modes, effectively detecting partial discharge phenomena within switch cabinets caused by insulation defects (such as tip discharge, floating potential, etc.), enabling early warning of equipment failures.
6. Coil and Energy Storage Element Testing Equipment
This type of equipment is specifically designed for testing the coils and energy storage elements of high-voltage switches. The specific tests include:
Open/Closed Circuit Coil Test: Independently measures the DC resistance and insulation resistance of the coil. Some devices integrate this function into the mechanical characteristic tester.
Energy Storage Motor Test: Measures parameters such as motor working current and energy storage time to determine the health status of the motor.
Capacitor Tester: Meets the requirements for the energy storage capacitor in the spring mechanism, measuring its capacitance and leakage current to evaluate the performance of the capacitor.
Post time: Jan-07-2026