I. Overview

This product is a resistive capacitive equipotential shielding voltage divider high voltage measuring device. Mainly used for measuring pulse high voltage, lightning high voltage, and power frequency high voltage. It has the characteristics of easy operation, intuitive display, high accuracy, small size, and light weight, and is suitable as an ideal equipment for high-voltage measurement in power plants, substations, high-voltage electrical equipment manufacturing plants, and high-voltage testing laboratories.

This AC/DC voltage divider is connected to the high-voltage measuring terminal through an instrument signal line, which can achieve clear readings from a long distance and is safe and convenient to use. This series of AC/DC voltage dividers has high input impedance and good linearity. Special shielding technology is used to reduce the impact of high voltage on the indication, thereby achieving high stability and linearity.

Using imported filling materials to make the structure smaller, lighter, more reliable, and reduce internal partial discharge. Small size, light weight, easy to carry, bringing great convenience to on-site inspection work.

2、 Technical parameters

Product standard: DL/T846.1-2004

Communication measurement methods: true effective value measurement, peak value (optional), average value (optional)

Accuracy: AC: 1.0% rdg ± 0.1 DC: 0.5% rdg ± 0.1

Insulation medium: Dry dielectric material

Environmental conditions: Temperature: -10 ℃~40 ℃ Humidity: ≤ 70% RH

Voltage division ratio: N=1000:1

3、 Usage method

1. The grounding terminal of the AC/DC voltage divider must be reliably grounded, otherwise it may lead high voltage to the outer shell of the meter head and cause electric shock accidents.

2. Connect the high-voltage wire above the voltage equalizing ring, tighten the high-voltage wire with a wiring screw, and ensure that the test wire does not protrude or tilt up or down to prevent measurement errors caused by discharge. If conditions permit, the test line can be placed in a metal shielding case to reduce interference.

3. Connect the signal aviation plug of the AC/DC voltage divider to the LCD display head. Turn on the power switch and select the appropriate measurement method according to the LCD screen prompts. Such as DC measurement or AC measurement.

4. After the test is completed, cut off the high voltage and wait for the LCD display meter connected to the AC/DC voltage divider to show a value of about "0. XXX" before entering the site (during the AC test, the instrument will slowly return to zero, but after the high voltage power supply is cut off, there is no power left, so please pay attention to the difference between AC and DC tests. After DC measurement, be sure to discharge with a discharge rod before proceeding with other work such as wire removal).

When measuring DC, if there is a filtering capacitor, the filtering capacitor should be fully discharged first, so that the reading indicated by the AC/DC voltage divider is about "0. XXX", and then relevant operations can be carried out.

During use and maintenance, attention should be paid to handling with care, and the surface of the AC/DC voltage divider should be kept clean to prevent contamination. This instrument should be placed in a dry place and properly stored.

4、 Precautions

1. During use, there should be no debris within 2-3 meters around the AC/DC voltage divider below 100KV (4 meters for 150KV-200KV AC/DC voltage dividers and 5 meters for 300KV AC/DC voltage dividers). The distance between the instrument, AC/DC voltage divider, and personnel should be determined according to the operating procedures for AC/DC voltage dividers in the power industry standards, and it is recommended to maintain a safe operating distance of at least 5-6 meters.

2. The AC/DC voltage divider should be placed in dry air and returned to the aluminum alloy chassis after use to prevent moisture. Adhere to the principle of handling with care and avoid collisions, squeezing, etc.

3. The LCD meter head is equipped with a lithium battery, which should be charged at least once a month if not in use for a long time, with a charging time of about 3 hours. Every time the battery level reaches around 40%, it should be charged immediately to prevent the battery from being "depleted" and unable to recover.

If there is a noticeable discharge sound during the experiment, it indicates that the surface of the voltage divider may be damp, and a dry hair dryer should be used to blow from top to bottom for 1-3 minutes; Preheat before the experiment and raise the voltage to a level that does not exceed the rated voltage but can hear the discharge sound for 5-10 minutes to remove moisture. When the environmental humidity exceeds 70% RH, it should be stopped from use, mainly because discharge will significantly affect measurement accuracy.

After completing the experiment, the voltage indication on the LCD meter head slowly decreases and gradually returns to zero. Due to the fact that the LCD meter of the voltage divider collects the voltage of the low voltage arm of the voltage divider, the low voltage arm voltage is the ratio of the high voltage arm voltage to the voltage divider. So when the high voltage end of the voltage divider is cut off, the floating potential of the microcontroller causes the LCD meter head to display non-zero, without any problems or affecting measurement accuracy.

6. The voltage divider and meter head, including the testing line, are an integrated system. During calibration, the meter head must be calibrated together with the corresponding voltage divider and testing line to ensure accuracy. By comparing the output with the standard voltage divider and its high-precision multimeter used for measurement calibration, the display can be checked for consistency. When submitting for inspection and verification, the standard voltage should be modulated to the voltage that can be measured by the voltage divider, so that the voltage divider and meter head can run for 2-3 minutes before reading, which will be more accurate.