Detection Technology
How to set the DC high voltage generator
The instrument generally meets the DC withstand voltage test of cables below 220KV voltage level under power frequency conditions, but in some special occasions, some cables and electrical rated voltage levels have special requirements.
In general test, it is necessary to slowly increase the voltage from 40% of the full test voltage to the full voltage for 5 minutes. If it is a new cable line that is less than one year old and the power outage is only one month, 50% of the specified test voltage can be done for 1 min. If the power outage is one year, it needs to be done in accordance with the general test requirements.
The specific test voltage and pressure time requirements for different cables, as well as specific test requirements, are described in detail in the power cable preventive test regulations.
1. Connect the ground terminal on the control box panel and the ground terminal of the high-voltage tower with a ground wire and connect it firmly to the ground wire of the site or laboratory. To ensure the safety of you and the equipment, please check the ground wire repeatedly. Ensure that all parts are well grounded,
Use the provided seven-core cable to connect the control box and the high-voltage tower. The two ends of the cable are the same fast aviation plugs. Pay attention to inserting the plug side notch into the thick convex part of the socket and tighten it clockwise. (Either end of the cable can be connected to the control box or High-voltage tower) connect the power cord, the power supply is single-phase AC 220v, power frequency 50hz,
2. If voltage regulation protection within the rated output voltage range is not required, turn the overvoltage protection setting button clockwise to the maximum value. At this time, when the output voltage exceeds the rated output voltage, it will automatically protect and cut off the high voltage. When performing voltage regulation protection within the rated output voltage range, please boost the no-load boost to the predetermined protection voltage according to the above steps, and then slowly turn the overvoltage protection setting knob counterclockwise to the required voltage. Voltage protection action, the "overvoltage" indicator light is on, keep the overvoltage protection setting knob at this position, return the boost knob to the zero position, turn off the power, connect the test product, then the boost will exceed the predetermined voltage in the future That is, the high voltage is automatically cut off.
3. Turn on the power switch. At this time, the power switch light (green) and the panel meter are on, and the high voltage indicator (green) is on. If the high voltage prompt buzzer is in the on position, it will beep to remind the operator that the high voltage is being applied. , At this time, turn the high voltage output adjustment knob clockwise to increase the voltage, the voltmeter displays the kv value of the voltage on the test product, and the ammeter displays the sum of the current flowing on the test product and all leakage currents, but does not include the built-in high voltage The current of the voltage divider, the current is in microampere unit ua.
If the power switch is turned on, the high voltage indicator light (green) is off, and the “return to zero” light (red) is on in the fault display, it means that the high voltage output adjustment button is not at the zero position. Please turn the button counterclockwise to “zero”. Turn the trimming voltage knob back to the zero position, and some "return to zero" lights will go out, and then adjust clockwise to increase the voltage.
4. When the load of the DC high voltage generator is a large capacitive load, in order to avoid overcurrent protection triggered by excessive charging current, please slow down the boost speed appropriately. After the test is completed, turn the output voltage adjustment knob counterclockwise to zero At this time, the voltmeter still shows the voltage value on the test product. Please wait for the test product to discharge below 20kv through the high-voltage tower before discharging with the ground rod to ensure safety.
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