The dielectric loss tester is a high-precision instrument used for fully automatic measurement of the tangent of dielectric loss angle (tgδ) and capacitance of various high-voltage power equipment at power plants, substations, and other field sites. Due to the adoption of frequency conversion technology, it can ensure accurate measurement under strong electric field interference. Applicable Fields

The dielectric loss tester is also suitable for measuring the tgδ and capacitance of high-voltage electrical equipment in workshops, laboratories, and scientific research institutions. It has advantages such as convenience, simplicity, and accuracy for testing the loss of insulating oil.

The dielectric loss tester can measure high-voltage electrical equipment that is ungrounded or directly grounded using positive or reverse connection methods.

The dielectric loss tester is internally equipped with a high-voltage step-up transformer and incorporates safety protection measures such as zero-crossing switching and lightning protection. During the test, it outputs high voltages of different levels from 0.5kV to 10kV, making operation simple and safe.

Instrument Measurement Circuit

The instrument measurement circuit includes a standard circuit (Cn) and a test circuit (Cx). The standard circuit consists of a built-in high-stability standard capacitor and the measurement circuit, while the test circuit consists of the test object and the measurement circuit. The measurement circuit is composed of a sampling resistor, a preamplifier, and an A/D converter. Through the measurement circuit, the amplitudes and phases of the current in the standard circuit and the test circuit are respectively measured. Then, using a microcontroller with digital real-time sampling and vector operations, the capacitance value and dielectric loss tangent of the test object can be obtained. 

The instrument has built-in anti-interference measures to ensure accurate measurement under external electric field interference. 

Control panel: printer, keyboard, display, and communication relay. Variable frequency power supply: uses SPWM open-loop to generate high-power sine wave with stable output.

Step-up transformer: boosts the output of the variable frequency power supply to the measurement voltage, with a maximum reactive power output of 2kVA/1 minute.  

Standard capacitor: internal Cn, measurement reference.

Cn current detection: used to detect the current of the internal standard capacitor, 10μA to 1A. Input resistance <2Ω. 

Cx positive connection current detection: only used for positive connection measurement, 10μA to 1A. Input resistance <2Ω. Cx reverse connection current detection: only used for reverse connection measurement, 10μA to 1A. Input resistance <2Ω.