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ZNC-1500C CNC Flame cutter repair

 


I was requested to visit the customer’s factory to inspect a flame cutting machine that was reported to be malfunctioning.
According to the customer, several control panel buttons were unresponsive, affecting normal machine operation. Additionally, when attempting to set a specific cutting length, the machine head failed to stop at the programmed position. Instead, it continued moving beyond the desired point.
Preliminary observation suggests that the stepper motors may not be holding (locking) properly at the commanded position, which could indicate a possible issue within the motor driver circuit, control signals, or the power supply to the motion control system.
After removing the cover, i observed that there was iron dust all over the internal parts of the machine. therefore i started to clean one by one.
 
 

 

Upon detailed testing of the control system, all four relays on the relay board were found to be malfunctioning and operating unreliably. These relays were affecting proper switching and control functions of the machine.

In addition, approximately twenty control panel push buttons were identified as defective or intermittently unresponsive, requiring replacement to restore reliable user input operation.

All identified faulty components were serviced accordingly. The relay board was repaired, and the malfunctioning buttons were replaced. Following these corrective actions, the system was restored to proper working condition.

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