1. Overcurrent protection action. One is the phenomenon of multiple current protection circuit action caused by low setting value of primary overcurrent protection or secondary overcurrent protection. At this time, the current protection setting value should be enlarged. Another is the phenomenon of overcurrent protection circuit action caused by circuit interference. A smoothing reactor should be added to the circuit to weaken the interference of the circuit.

2. Damage to the intermediate frequency furnace potentiometer or voltage failure of the potentiometer usually causes this phenomenon. When encountering this phenomenon, the potentiometer should be replaced in time.

3. The load increases a lot, but the DC equivalent resistance of the load is too small, resulting in low DC voltage and large DC current, causing the phenomenon of difficult circulation and inverter circuit subversion. The induction coil should be replaced to increase the load equivalent resistance.

4. The light load causes the DC voltage and intermediate frequency voltage to reach the rated value, but the intermediate frequency current is very small, and the intermediate frequency power does not reach the rated value. When this phenomenon occurs, the capacitance should be increased to increase the intermediate frequency power.

5. The withstand voltage of the electric heating capacitor is reduced or the base of the electric heating capacitor is discharged due to dust, water, oil and other impurities. At this time, the copper plate on the capacitor should be removed and tested with a 1000V megohmmeter. If it is not insulated, the dust, water, oil and other impurities on the base of the electric heating capacitor should be cleaned in time or the capacitor should be replaced.

6. Due to the short circuit between the turns of the induction coil or the short circuit between the induction coil and the ground, the overvoltage protection circuit or the overcurrent protection circuit is activated. At this time, the induction coil should be checked to ensure that the turns of the coil are clean, and the arc powder and dust around the induction coil should be cleaned.