Before operation, the maximum working current should be calculated and the current protector adjusted according to the capacity and voltage level of different test samples. The test wiring should refer to the diagram in the instruction manual or the relevant connection diagram in the test transformer, and the grounding terminal should be well grounded.

Connect the power supply (the box type is a socket type power supply, and the test transformer control desktop is a terminal type power supply), and turn the voltage regulator handle to the zero position. The zero position switch is closed, and the zero position indicator light (yellow light) is on (also known as the zero position output status indicator of the voltage regulator);

Press the start button (green), the contactor is engaged, the voltage regulator is powered on, and the working indicator light (red light) lights up and emits an alarm sound (the alarm sound can only stop after the voltage regulator leaves the zero position);

Rotate the voltage regulator handle slowly and evenly clockwise, and closely monitor the instrument reading. When the desired high voltage value is reached, stop rotating the handle and press the timer button (yellow) in a timely manner. At this time, the digital time relay will display the time in a clockwise direction (timing unit is "s", seconds). When the set time is reached, the test transformer control panel will sound and light an alarm. Rotate the voltage regulator handle in the opposite direction in a timely manner until the voltage regulator returns to zero, and then release the timer button.

During the boost or withstand voltage test, if there is an overcurrent such as short circuit, flashover, breakdown, etc., the current relay protection will trip, and the voltage regulator will automatically cut off power, indicating that the tested product is unqualified. At this time, the voltage regulator should be reset to zero, the power supply should be cut off, and the tested product should be inspected.