Product Details

2. The test site voltage of the partial discharge tester can be as high as tens of thousands of volts. Test personnel should strictly comply with all safety precautions. The test area should have clear and visible warning signs, and everyone on site should be aware of the high-voltage area. Personnel directly involved in measurement should understand all live and high-voltage components in the measurement circuit. Personnel not directly involved in measurement should be isolated from the test area. During the test and after power-up, no one is allowed to enter the high-voltage area.

3. Before the test, operators should master the test circuit, test method, test procedure, and test purpose.

4. The test site should be clean and tidy, and no unrelated items should be stored. There should be no scattered small metal pieces (such as bare copper wire segments, screws, nuts, and other small metal pieces) on the ground in the high-voltage area. The test object, step-up transformer, coupling capacitor, etc. should be kept at appropriate distances from the surroundings.

5. The surfaces of the test object, step-up transformer, coupling capacitor, etc. should be kept dry and clean, as surface moisture and dirt can cause surface partial discharge, leading to abnormal measurements.

6. Test operators should connect the circuit according to regulations. All metal objects in the test area should be firmly grounded. Check and improve any parts that may cause discharge in the test area (e.g., no sharp or acute angles), and pay special attention to whether all ground wires are properly grounded.

7. Before applying voltage, test personnel must thoroughly and comprehensively check the circuit to avoid incorrect connections. Special attention should be paid to whether the ground wire, high-voltage wire, and strong current circuit connections are firmly connected.

8. In case of abnormal test conditions, first cut off the power supply, then proceed with further handling.

(IV) Precautions

1. Before applying voltage, test personnel must thoroughly and comprehensively check the circuit to avoid incorrect connections. Ensure that the ground wire at the test instrument is firmly connected to the grounding body. If the connection is not secure or the wire is accidentally kicked off during preparation, it may cause personal injury and equipment damage.

2. For connecting wires, avoid exposing sharp tips to prevent corona discharge at the tips. Especially for partial discharge tests at higher voltage levels, it is necessary to thicken the high-voltage connecting wires and install anti-corona shields to reduce corona discharge caused by excessive field strength. The shielding cover should not come into contact with the porcelain skirt of the test object.

3. Generally, during the test, the partial discharge level of the test object during withstand voltage and pre-boost is much higher than normal, and the instrument's meter will inevitably exceed full scale. To prevent instrument damage, turn the coarse gain adjustment knob counterclockwise by one or more steps to keep the reading within full scale. When the voltage drops to the measurement voltage, turn the coarse gain switch clockwise by one or more steps to record the measurement value.

I. Fault finding in GIS switch drive mechanisms to prevent switch refusal and misoperation accidents

GIS is the most important switchgear in today's power systems. Whether the switches inside GIS operate correctly is a key factor in the safe operation of the power grid. High-voltage GIS switch operations are mostly driven by hydraulic or compressed air. To ensure the normal operation of hydraulic and pneumatic drive systems, the motor must be started periodically to apply pressure and verify the system's reliability. However, due to manufacturing defects, installation issues, or improper maintenance, equipment failures, even air compressor damage, causing reduced drive speed or failure, are increasing, seriously threatening the stable operation of the power grid and directly affecting people's lives and production, with severe social consequences. The SDT electrical equipment partial discharge patrol tester uses advanced ultrasonic principles and sophisticated sensing technology to vividly detect internal leaks in hydraulic and pneumatic systems, identify drive faults early, and notify maintenance personnel via digital and audible alarms to eliminate defects, ensuring the safe operation of GIS.

II. Insulator pollution flashover and internal crack detection, cable joint partial discharge detection

Various internal crack faults and external pollution faults of insulators also urgently require effective methods for detection. When the air around insulators is ionized, chemical reactions occur, corroding metal parts and weakening the insulation capability. The high energy generated by corona discharge can cause severe damage to mechanical components, leading to unplanned outages and affecting thousands of service customers, and in severe cases, can cause fires and explosions. Especially in factories, fires and explosions caused by electrical partial discharge can have serious chain reactions due to the presence of hazardous and toxic chemicals. Traditional infrared imaging technology can detect hot spots invisible to the naked eye. However, partial discharge, corona, arcing, and tracking phenomena do not necessarily accompany significant temperature rises, and ambient high temperatures can mask these phenomena. However, these phenomena generate ultrasonic noise, which can be accurately detected using ultrasonic detection equipment.

III. Internal partial discharge fault detection in GIS/GCB, switchgear cabinets, power cabinets, and communication cabinets

Partial discharge faults inside GIS/GCB in power plants and substations, as well as in switchgear cabinets in centralized control rooms, are increasing. There is an urgent need for appropriate detection methods for predictive maintenance and alarm. The SDT electrical equipment partial discharge patrol tester is timely. Depending on the insulating medium of GIS/GCB, the propagation speed of internal and external partial discharge varies. Detection methods using chromatography or electrical measurement are not only cumbersome, dangerous, and expensive but also cannot provide real-time detection. Electrical maintenance personnel urgently need a detection method that is simple to operate, reasonably priced, and safe for spring and autumn inspections and routine predictive maintenance. The SDT electrical equipment partial discharge patrol tester fully meets these requirements.