Dielectric Loss General Tester

HD91 automatic anti-interference dielectric loss tester

Performance characteristics:

1. Automatic and simple wiring is simple (two wires for positive connection, one wire for reverse connection), all cables are grounded and shielded, so they can be used by mopping the ground, measuring voltage rises and falls slowly, automatic measurement, The result is read directly without conversion.

2. A variety of measurement methods. Positive/reverse wiring, internal/external standard capacitors and internal/external test voltages can be selected for measurement. Positive wiring can measure high voltage dielectric loss

3. Seismic performance The instrument can withstand strong vibrations and bumps during long-distance transportation without damage.

4. Strong anti-interference ability. The automatic tracking interference compensation circuit is used, and the vector operation method and the phase shift method are combined to effectively eliminate the influence of strong electric field interference on the measurement. It is suitable for field tests of 500kV and below power stations.

5. CVT measurement Unique self-excitation method to measure CVT function, without any additional equipment, can complete the measurement of non-detachable CVT. One connection (three cables, no wire reversal), one measurement process (about 1 minute), two final measurement results (the dielectric loss and capacitance value of C1 and C2). The measurement process is displayed in Chinese, which can monitor the self-excited current value and the test voltage (high voltage) value in real time. It can eliminate the influence of the lead wire on the test, and the measurement result is accurate and reliable.

6. Safety measures

(1) High-voltage protection: short-circuit, breakdown or high-voltage current fluctuation of the test product can quickly cut off the high-voltage output.

(2) CVT protection: Set the overcurrent point of the self-excited voltage. Once it exceeds the set current value, the instrument will automatically exit the measurement without damaging the equipment.

(3) Grounding detection: The instrument has a grounding detection function, and it cannot be used for boost measurement when it is not grounded.

(4) Misoperation prevention: It has an anti-misoperation design, can distinguish common wiring errors, and give a safe alarm.

(5) Anti- "capacity rise": The "capacity rise" effect of voltage increase will occur when measuring large-capacity samples. The instrument can automatically track the output voltage and keep the test voltage constant.

7. The VFD display adopts a novel large-screen VFD dot matrix display, which can display normally at minus 40°C. Full Chinese operation menu, operation prompts various warning messages, intuitive and clear, you can operate without consulting the manual.

Technical index:

Dielectric loss (tgδ) measurement range: 0~100% resolution 0.01%

Capacitance (Cx) measuring range: internal connection method: 3pF~40000pF/10kV 60pF~0.8μF/0.5kV

External method

(1) "External booster method" (external high voltage, internal standard capacitor) Maximum test voltage 10kV

(2) "External Cn" method" (external high voltage, external standard capacitor)

The highest test voltage is determined by the standard capacitor and the tested product (Umax=Imax/ωCn)

Maximum test current of standard circuit (Imax): 1A (In=UωCn)

Maximum test current of the tested circuit (Imax): 1A (Ix=UωCx)

Internal booster output capacity: 0.5kV~10kV (divided into 20 levels) Maximum output current: 140mA at 10kV

Basic measurement error

The product should meet the requirements of Table 1 when the ambient temperature is 20℃±5℃ and the relative humidity is 30%~85%. (The change in the basic error of the instrument for every 10°C change in temperature does not exceed 1/2 of the basic error limit.)

Table 1

Measurement parameters


Basic error

Dielectric loss tgδ



Reverse connection


Electric capacity Cx



Reverse connection


Working power supply: 220V±22V 50±5Hz power supply from mains or generator

Environment temperature: -10℃~50℃

Environmental humidity: 30%~85%

Contact us

No. 255, Shanpu Road, Hedong Industrial Park, Wuzhong Economic Development Zone, Suzhou City, Jiangsu Province




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