In substation maintenance and preventive testing, field operation and maintenance personnel often need to accurately measure the dielectric loss factor and capacitance of high-voltage equipment under strong electromagnetic interference. The HY-8000B variable-frequency anti-interference dielectric loss tester uses 45Hz/55Hz variable-frequency output and digital notch filtering technology to complete measurements under conditions of no power outage or strong electric field interference. The instrument supports various wiring modes such as positive connection, reverse connection, external connection, CVT self-excitation method, and internal/external standard capacitors, internal/external high voltage, adapting to test samples with different grounding conditions. It has a built-in SF6 standard capacitor and high-voltage source, requires no external voltage-boosting equipment, and its integrated design facilitates field carrying and operation.
For capacitor voltage transformers (CVT), the instrument supports simultaneous C1/C2 measurement, measurement without disconnecting leads, and reverse connection low-voltage shielded C0 measurement, automatically compensating for the effects of busbar grounding and standard capacitor voltage division. With one wiring setup, tgδ and capacitance can be obtained, and the transformation ratio and phase error can also be tested. For power transformers, it can measure the dielectric loss and capacitance between windings and between windings and ground, evaluating the condition of transformer oil and overall insulation; for voltage/current transformers (PT/CT), it can measure the insulation performance of the primary to the secondary and ground. The automatic identification function can distinguish capacitive, inductive, and resistive test samples, and automatically identify 50Hz/60Hz power supply frequency, reducing manual setting steps.
Equipped with a standard oil cup and temperature control device, the instrument can accurately measure the dielectric loss factor of insulating oil and determine the degree of oil deterioration. In laboratory material research, it can measure the dielectric constant and loss angle of materials such as insulating paper, insulating film, plastics, and ceramics, with reference to standard methods such as GB/T 1409-2006 and the GB/T 31838 series. The instrument has a built-in calendar chip and micro printer, and supports USB flash drive/RS232 data export, facilitating later analysis and archiving.
The instrument has high-voltage short-circuit/breakdown/overcurrent protection, grounding detection (voltage boost is locked if not grounded), misoperation prevention, prevention of the "capacitance rise" effect (automatic tracking of output voltage), and electric shock protection (immediate high-voltage cutoff upon accidental contact). During field use, before testing confirm that the ambient temperature is ≥+5°C and humidity is ≤80%, and that the test sample surface is clean and dry; the instrument grounding terminal must be reliably grounded; before testing, the equipment under test must be completely de-energized and fully discharged, and a grounding wire must be properly connected; correctly select the positive connection or reverse connection according to the grounding condition of the test sample, and keep the high-voltage cable at a sufficient safe distance from ground; during measurement, it is strictly prohibited to operate the test voltage selection switch; after testing is completed, first cut off the power, then fully discharge the test sample before touching it.
Measurement range: tgδ 0～100%, capacitance 0～100000pF; resolution: tgδ 0.001%, capacitance 0.001pF; accuracy: capacitance ±(reading×1.0%+1.0pF), tgδ ±(reading×1.0%+1.0PF); test ambient temperature: 10℃～30℃ (the LCD screen should avoid prolonged sunlight exposure); power supply: AC 220V±10%, 50Hz±1%; dimensions and weight: approximately 20-30kg, subject to the actual product.
