Dielectric loss tester measures the phase angle difference between voltage and current
The dielectric loss tester (referred to as the loss tester) is a precision automated instrument specifically used to measure the dielectric loss tangent (tgδ or tanδ) and capacitance (Cx) of insulating materials in high-voltage power equipment. It is like a precision instrument that conducts a "physical examination" on high-voltage equipment such as transformers and cables, using subtle numerical changes to determine whether the equipment's insulation is damp, aged, or deteriorated.
Given that you are in Yangzhou, Jiangsu, it is worth mentioning that Yangzhou is an important industrial base for power testing equipment in China, with well-known loss tester manufacturers such as Yangzhou Haotai Electric and Zhili Electric.
⚙️ Core Working Principle
The loss tester operates based on vector operations under an AC electric field:
Dielectric loss tangent (tgδ): Under AC voltage, insulating materials consume a small amount of electrical energy, converting it into heat. The instrument calculates the tgδ value by measuring the phase angle difference between voltage and current. The smaller this value, the lower the energy loss of the insulating material, and the better the insulation performance.
Digital measurement: Modern loss testers contain a standard circuit (with a built-in high-stability standard capacitor) and a test circuit. The high-speed sampling circuit measures the current amplitude and phase difference of the two circuits, and then uses a digital signal processor (DSP) for vector operations to ultimately obtain the tgδ value and capacitance of the test object.
