The dielectric loss tester works based on the complex current method / vector current method
The Dielectric Loss Tester is a precision instrument used to evaluate the insulation performance of high-voltage power equipment. By measuring the dielectric loss tangent (tgδ or tanδ) and capacitance (Cx) of insulation materials, it determines whether the equipment has safety hazards such as moisture ingress, aging, or partial defects.
Simply put, it is the health check device for power equipment, widely used in power plants, substations, laboratories, and cable and transformer manufacturing plants.
The following is a detailed introduction to the dielectric loss tester:
Core Working Principle
The dielectric loss tester works based on the complex current method (vector current method).
Apply Voltage: The instrument internally generates high-voltage AC (typically 0.5kV~10kV) and applies it to the equipment under test.
Collect Signals: A circuit is formed through the standard capacitor (Cn) and the test specimen (Cx), collecting current amplitude and phase respectively.
Calculate and Analyze: Using a Digital Signal Processor (DSP), the phase difference between voltage and current is calculated to obtain the dielectric loss angle δ and its tangent value (tanδ).
tanδ Value: Reflects the power loss per unit volume of the insulation material. The larger the value, the worse the insulation performance (such as moisture ingress or aging).
Capacitance Cx: Used to detect geometric changes in the insulation structure (such as capacitance changes caused by wire breakage, short circuits, or moisture ingress).
