CPU fault
Mitsubishi Electric · FR E700
¿Qué significa E.6 ?
This is a CPU fault that stops the inverter output when a communication fault occurs within the built-in CPU. Specific causes include excessive electrical noise or a short circuit between the PC and SD terminals. This critical internal error prevents safe operation.
Causas comunes
- Excessive electrical noise or electromagnetic interference (EMI) disrupting internal CPU operations or serial communications.
- Short circuit condition between the PC connection port and the 'S' signal terminal on the control board.
- Damage to the internal serial communication interface (UART/USART) hardware on the CPU.
- Improper grounding or ground loop issues affecting serial communication lines.
- Firmware execution error leading to a CPU watchdog timeout.
Pasos de reparación & Lista de verificación
Haga clic en los pasos para seguir su progreso.
- 1
Disconnect all external devices from the inverter's communication ports (e.g., PC, PLC, HMI) including RS-485 terminals (RDA, RDB, S).
- 2
Power cycle the inverter completely (remove AC input power for 60 seconds) after disconnecting external communication devices.
- 3
Measure the resistance between the designated 'PC' signal terminal and the 'S' signal terminal to detect a short circuit.
- 4
Inspect the communication cable for physical damage, proper shielding, and correct termination resistors.
- 5
Verify that the 24VDC control power supply voltage is stable and within specified tolerance.