1. Close the working power of the inverter cabinet and check the regulated power supply (using a multimeter)

Whether +15V, -15V, +24V, +30V, +130V meet the requirements.

Check whether the GND ground wire in each inverter cabinet is connected.

Check if the working power of the inverter pulse transformer is normal.

Check whether the inverter stop light (red) is on, according to the inverter work, whether the inverter work light (green) is on, press reset, whether the inverter work light (green) is off, and whether the inverter stop light (red) is on. Press the inverter to work, the green light is on, press the inverter to stop, the red light is on. Repeat the operation several times.

The green and red lights are off, and if the button is not working, check the load distribution board for any problems and the connection to the inverter board.

2. The switch on the inverter main board is in the inspection file, and the frequency is displayed according to the inverter. Detect the KK tube trigger pulse with an oscilloscope. (with oscilloscope DC file)

When detecting the inverter pulse, each pulse should check its negative bias. The method is: after the pulse is detected, the oscilloscope level is turned to GND, and the pulse below the pulse is 0.3V under the GND.

If there is no negative bias, check the 380V/10V, 10V, 10V, 10V power transformer.

3, the correction frequency (frequency table display and inspection frequency are consistent)

Check the frequency potentiometer W110 and adjust the frequency at 300HZ (detected with an oscilloscope)

Correct the frequency potentiometer W201, adjust the potentiometer to make the frequency meter display 300HZ

4. Test machine: (Requirement: The inverter main board is in the working file. The furnace is placed inside the furnace, and the internal and external water systems are turned on)

Close the knife switch and press the energy storage, closing, and rectification work buttons.

DC voltage rises to full voltage (DC voltage = incoming voltage × 1.35 × 2)

Use the oscilloscope probe to detect the current waveform on the inverter current transformer 5A/0.1A.

The oscilloscope detected the waveform as follows

If the power potentiometer is adjusted and the current waveform cannot be moved, the two current signal lines from the inverter main circuit are exchanged.

After the input current signal line is correct, adjust the power potentiometer to the zero position, and adjust the lower limit potentiometer W162 in the critical state (the second waveform above).