Sharing experience in troubleshooting plasma cleaners

A plasma cleaner basically consists of a power supply, matching network, chamber, solenoid valves, flow meters, external gas supply, vacuum pump and control circuit. When a fault alarm occurs, we should first use the alarm prompt on the screen to see which part has triggered the alarm, which identifies the approximate location of the fault, and then check whether the actuators in that part are abnormal. For control circuit faults, the most direct and simplest method is to test with a multimeter, checking for short circuits or open circuits and whether the voltage and current are normal. If you need to troubleshoot without a multimeter, the fastest method is substitution: first use the screen prompt to roughly locate the fault, then replace the suspect part with an identical component. If the fault lies in an electrical component such as an AC contactor, thermal overload relay, intermediate relay, phase sequence protector or flow meter, this quickly solves the problem.

If there is a gas under-pressure alarm, you need to confirm whether gas is connected to the relevant gas inlet, whether the gas pressure, pressure regulator, flow meter, solenoid valve and analog wiring are all OK, and whether the related parameter settings on the screen are all correct. When there is an alarm for the vacuum reading being too high or too low, first check the parameter settings. When the vacuum reading is too high and the parameter settings are OK, you need to check the chamber and piping for leaks and check whether the pump-down pressure of the vacuum pump is normal. The fastest way is to connect the vacuum gauge supplied with the equipment directly to the vacuum pump and measure whether the pump's pump-down value meets the standard. If the pump-down value is normal, the vacuum pump is fine. Then connect the gauge to the pumping line and measure again; if the reading is much higher than when the gauge is connected directly to the vacuum pump, the pumping line is leaking. A pumping line leak may be at a pipe joint or caused by damage to the pipe. Although the pumping line is made of stainless steel, if it shakes during each pump-down and rubs against some nearby part, over time it can also wear through. If there is no obvious difference between the vacuum reading measured on the pumping line and that measured directly on the vacuum pump, the pumping line is also fine, and the only remaining step is to look for the leak in the chamber sealing. Possible chamber leak points are the sealing strip, the glass window, the connection between the pumping port and the outside, the connection between the electrode and the outside of the chamber, and the connection between the chamber vent and the outside; the most likely leak points are the sealing strip and the glass window.

Faults in the power supply and matching network will also display related prompt messages in the alarm window on the screen when triggered, but false alarms can sometimes be triggered by parameter settings and other causes, which must be analyzed case by case. When the power supply or matching network fails, first confirm that the parameter settings are all correct, then check whether the wiring and the voltage signal that sets the power output are correct and reasonable, and whether serial communication between the matching network and the power supply is normal. Then debug manually: if, when adjusting the matching network parameters, the relevant parameters do not change noticeably when the increase/decrease buttons are pressed, the matching network is faulty; if the power output does not change when the power level is adjusted, the power supply is faulty.