The dielectric loss tester is a high-precision instrument used for fully automatic measurement of the dielectric loss tangent (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 edit

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 insulation oil loss testing.

The dielectric loss tester can measure high-voltage electrical equipment that is ungrounded or directly grounded using positive and reverse wiring 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 edit

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 amplitude and phase of the current in the standard circuit and the test circuit are respectively measured, and then the microcontroller uses digital real-time acquisition methods and vector operations to obtain the capacitance value and dielectric loss tangent of the test object. 

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 regulated output.

Step-up transformer: boosts the variable frequency power supply output 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～1A. Input resistance <2Ω. 

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