MaytinhcongnghiepFault diagnosis
Answer a few questions to narrow down the cause. The steps follow the order technicians actually use: rule things out from the outside in, from cheap to expensive.
What is the machine doing?
No power at all Pressing the button does nothing Powers on but no display Fans spin, LEDs on, screen stays black Shuts down or freezes while running Runs for a while, then drops out Lost connection to devices on COM ports PLC or inverter not responding Touch screen erratic or unresponsive Touch one spot, cursor jumps elsewhere
Before opening the machine. Disconnect power, wait for capacitors to discharge, and photograph the current wiring. If the machine is under warranty, call us first — opening it yourself may void the warranty.