Introduction to Power Frequency High Voltage Generator

Characteristics of Power Frequency High Voltage Generator

1. Small size, light weight, more beautiful, more reliable, easy to operate, complete functions, suitable for field use, it is an ideal reliable product in the new century.

2. Adopting advanced technology and manufacturing processes, it is the first to apply new PWM high-frequency pulse width modulation technology, pulse train logic array modulation, using high-power IGBT devices, using high-frequency technology to increase frequency up to 100kHz, thereby making the output high voltage more stable and the ripple coefficient smaller.

3. High precision and accurate measurement. Voltage and current are digitally displayed, with voltage resolution of 0.1kV and current resolution of 0.1uA. The voltmeter on the control box directly displays the voltage value applied to the load test object, so no external voltage divider is needed, and wiring is simple. The instrument has high and low voltage terminals for measuring leakage current. The high voltage terminal uses a circular digital meter display, which is not afraid of discharge impact, has good anti-interference performance, and is suitable for on-site use.

4. High voltage regulation stability, smooth voltage regulation across the full range. The output voltage adjustment uses an imported single multi-turn potentiometer, with smooth boosting process, high adjustment precision, and coarse and fine adjustment functions. Voltage regulation is better than 0.1%, voltage and current measurement error is less than 1.0%, and ripple factor is better than 0.5%.

5. Negative output, zero start, continuously adjustable, with overvoltage, overcurrent, return-to-zero, grounding protection, unique disconnection protection and other protection functions. The automatic protection circuit has strong functions, complete and reliable protection, making operation safe, and all technical indicators are better than industry standards and similar products.

6. Added high-precision 75% VDC-1mA function, bringing great convenience to zinc oxide arrester measurement. A simple press without calculation. The control box of this instrument has a 75% voltage function key. When doing zinc oxide arrester test, when the current rises to 1000uA, press the 0.75 button. At this time, the values displayed on the voltmeter and ammeter are the 75% data. After completion, immediately return the boosting knob to zero, and also return the fine voltage adjustment knob to zero, and immediately press the green button to cut off high voltage and turn off the power switch. Then do other tests.

7. Convenient overvoltage setting function, using digital dial switch, can directly display the set voltage value, making your operation more casual, the displayed value unit is kV.

8. The voltage doubling cylinder can be of segmented structure, flexible and convenient for field use, one machine with multiple uses, economical and practical.

Usage Precautions

1. Personnel using the high voltage generator must be professionals with a "High Voltage Test Work Permit".

2. When using this instrument, users must comply with Article 168 of the "Electric Power Safety Regulations" and install two obvious disconnection points before the working power enters the tester. When replacing test objects and wiring, first clearly disconnect the two power disconnection points.

3. Before testing, please check whether all test wiring, control box, voltage doubling cylinder, and test object grounding wires are properly connected. The test circuit grounding wire should be grounded at one point according to the requirements of this instrument manual.

4. For discharging large capacitance test objects, use a dedicated discharge rod to discharge the test object. When discharging, do not immediately contact the test object; gradually approach the test object. At a certain distance, air gap starts to ionize and discharge, with a hissing sound. When there is no sound, use the discharge rod to discharge, then directly connect to the ground wire for discharge.

5. When DC high voltage is 200KV and above, even if test personnel wear insulating shoes and are in a safe distance area, due to the influence of the DC high voltage ion space electric field distribution, several nearby standing people may carry different DC potentials. Test personnel should not shake hands with each other or touch grounding bodies with hands, otherwise there may be slight electric shock phenomena. This phenomenon is more obvious in dry areas and winter, but because the energy is small, it generally does not cause harm to the human body.

6. The power supply of the power frequency high voltage generator control box is AC220V±10%, 50Hz. If the power supply passes through a 1/1 isolation transformer or uses on-site self-generated power, it is necessary to artificially connect one point of the power supply to the earth.

Fault Inspection and Handling:

1. When the power switch is turned on, if the digital display on the control box does not light up, please check the power connection and all fuses. If the fuse is damaged, replace it with a new fuse according to the amperage marked next to the fuse holder.

2. If the digital display lights up when the power switch is turned on, but the high voltage green light does not light up and high voltage cannot be applied.

(1) Fault display "Return to Zero" light is on: Not returned to zero position. Please turn the high voltage output adjustment knob and fine adjustment knob counterclockwise back to zero until the "Return to Zero" light goes off, then high voltage can be applied.

(2) Fault display "Other" light is on, there are two phenomena: grounding protection; disconnection protection. a. Possibly the grounding wire is not connected properly, or the ground wire is not reliably grounded. Please connect a reliable grounding wire, turn off the power, and restart. b. Possibly the cable connecting the control box and the high voltage tower is not connected properly. Connect the cable, turn off the power, and restart. Or if the solder joints at both ends of the cable wire are desoldered, this fault will occur. Please solder the solder joints at both ends of the cable, turn off the power, and restart. c. Possibly a wire joint inside the control box is desoldered and disconnected. Please re-solder it, turn off the power, and restart.

3. Everything is normal, but protection occurs before reaching the rated output voltage.

(1) Fault display "Overcurrent" light is on: a. Test object short circuit, or leakage current too large. b. When large capacitance load, boosting too fast. Turn off the power, restart, and slow down the boosting speed.

(2) Fault display "Overvoltage" light is on: The overvoltage protection setting knob is not placed at the maximum position. Please turn it clockwise to the maximum position, turn off the power, and restart.

4. When a short circuit occurs under high voltage on the test object, due to the large short circuit current, it is possible that all fault display lights are lit, which is normal. Please eliminate the test object fault and restart.

5. After the test object fault is eliminated, the fault display light is still on and high voltage cannot be applied. The power switch also serves as the fault protection reset switch. Please turn off the power and restart to boost voltage.

6. If the voltmeter digital fluctuation is too large, please check whether the 7th pin joint of the aviation plug at both ends of the connecting cable is desoldered and disconnected. If disconnected, please solder it.

Technical Reference Standards:

IEC 60-1: 1989 High voltage test techniques - Part 1: General test requirements

GB/T 16927.1-1997 High voltage test techniques - Part 1: General test requirements

IEC 60-1: 1994 High voltage test techniques - Part 2: Measuring systems

GB/T 16927.1-1997 High voltage test techniques - Part 2: Measuring systems

DL 474.2-92 Guide for on-site insulation tests - DC high voltage test

ZBF 24002 Guide for the use of on-site DC and AC withstand voltage test voltage measuring devices