Detection Technology
Working principle of gas-filled test transformer
Working principle of gas-filled test transformer:
Input the power supply to the operation box with automatic over-current tripping and zero-position interlocking device to prevent sudden pressure. The voltage is adjusted by the auto-coupling regulator and input into the primary winding of the YDQ test transformer. According to the principle of electromagnetic induction, the The winding can obtain the same multiple of the voltage amplitude-power frequency high voltage according to the ratio of the winding to the number of turns of the primary winding. This power frequency high voltage can be obtained by high voltage silicon stack rectification and voltage regulator capacitor filtering to obtain DC high voltage, and its amplitude is twice the effective value of power frequency high voltage.
Steps:
1. Connect according to the above figure, check whether the internal gas pressure indicated by the pressure gauge is normal (≥0.3MPA)
2. When doing AC withstand voltage, insert the short-circuit bar into hole J, do a DC leakage test, and take out the short-circuit bar.
3. Current-limiting resistor configuration: power frequency withstand voltage 0.3~1 ohm per volt: DC 5~10 ohm per volt, general test is not necessary.
4. Remove the lead of the tested product line, clean the casing and the body of dirt, and adopt shielding measures if necessary.
5. The preparations and safety measures are in place, and the equipment should be tested empty.
6. Connect the tested product, and use shielded wire for DC test to eliminate stray leakage.
7. Turn on the power supply, and the green light of the power supply command of the control box (cabinet) will be on.
8. Press the start button, the start indicator light is on.
9. Power up the control box evenly clockwise, and watch the voltage expression reach the rated voltage value.
10. Continue to specify the withstand voltage time and watch the ammeter instructions.
11. When the withstand voltage time is up, watch the KV meter and drop to zero quickly and evenly.
12. After doing the experiment in Figure 2, use a discharge rod to discharge through the resistance, and then directly ground the discharge.
13. After the high-voltage parts may be discharged one by one by the charging parts, change or remove the high-voltage leads, and all leads will be terminated at this time.
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