E.PE fault in Mitsubishi FR-E700 Drive

E.PE Parameter Storage Device Fault in the Mitsubishi FR-E700 Drive indicates that the parameter storage device (EEPROM) on the control circuit board has developed a fault. The FR-E700 stores drive parameters in non-volatile EEPROM memory so that settings are retained after power is removed. If the EEPROM cannot reliably read or write parameter data, or if the EEPROM has reached its write endurance limit due to excessive parameter updates, the drive generates E.PE and may prevent normal operation.

This fault generally indicates a problem with the control circuit board or EEPROM memory, rather than the motor or power section.

Possible Causes

• EEPROM memory failure.
• EEPROM write endurance exceeded due to excessive parameter writing.
• Frequent parameter updates via communication.
• Corrupted parameter data.
• Control circuit board malfunction.
• Internal memory circuit failure.
• Electrical surge damaging the EEPROM.
• Power interruption during parameter writing.
• Aging of the EEPROM memory device.
• Internal PCB fault.

Solutions

• If parameters are written frequently through communication, set Parameter Pr.342 = 1 to enable RAM Write and reduce EEPROM write operations.
• Cycle power to the drive and verify whether the fault clears.
• Check whether recent parameter changes caused the fault.
• Minimize unnecessary parameter writing during operation.
• Back up the drive parameters if possible.
• If the fault persists, contact your Mitsubishi sales representative or authorized service center.
• Replace the control circuit board if the EEPROM is defective.

Additional Information

The Mitsubishi FR-E700 stores all user parameters in an internal EEPROM (Electrically Erasable Programmable Read-Only Memory).

EEPROM devices have a limited number of write cycles. Repeated parameter updates—especially via PLC or serial communication—can eventually wear out the memory.

Fault E.PE is generated when:

• The EEPROM cannot reliably store parameter data.
• The EEPROM has exceeded its write life.
• The control circuit board detects a memory fault.

According to Mitsubishi, if parameters are written frequently via communication, set:

• Pr.342 = 1 (RAM Write Enabled)

This stores parameter changes temporarily in RAM during operation, significantly reducing EEPROM write cycles and extending memory life.

Unlike a parameter setting error, E.PE indicates a hardware memory storage problem.

Common Symptoms

• Drive displays E.PE Parameter Storage Device Fault.
• Parameters cannot be saved.
• Parameter changes are lost after power cycling.
• Drive may fail during initialization.
• Communication parameter writes may fail.
• Fault appears after frequent parameter updates.
• Drive may not operate normally.
• EEPROM-related alarms continue after reset.
• Control board replacement may be required.
• Fault remains until the memory problem is corrected.

Recommended Troubleshooting Sequence

1. Verify that the fault is E.PE Parameter Storage Device Fault.
2. Disconnect power and follow lockout/tagout procedures.
3. Restore power and confirm the fault.
4. Determine whether parameters are being written frequently through communication.
5. If applicable, set Pr.342 = 1 (RAM Write Enabled).
6. Minimize repeated parameter writing.
7. Check whether parameters are retained after a power cycle.
8. Back up parameter settings if possible.
9. Inspect the control circuit board for signs of damage.
10. If the fault persists, suspect EEPROM failure.
11. Replace the control circuit board if required.
12. Restore the saved parameter settings after replacement.
13. Test normal drive operation.
14. Verify that parameter storage functions correctly.
15. Contact Mitsubishi technical support or your sales representative if additional assistance is required.

E.PE Parameter Storage Device Fault Check Table

Check Point	Action
EEPROM operation	Verify parameter storage function
Parameter writing	Reduce excessive write operations
Pr.342	Set to 1 for RAM Write when frequent communication writes are used
Power cycle	Confirm parameters are retained after restart
Control circuit board	Inspect and replace if faulty
Parameter backup	Save parameters before replacing hardware
Drive operation	Verify normal operation after repair
Mitsubishi support	Contact if the fault persists

Preventive Maintenance Tips

• Avoid unnecessary or continuous parameter writing via PLC or communication networks.
• Enable Pr.342 = 1 (RAM Write) in applications requiring frequent parameter updates.
• Back up drive parameters regularly.
• Protect the drive from power interruptions during parameter changes.
• Use a stable power supply to prevent memory corruption.
• Protect the control board from electrical surges.
• Keep the drive clean and free from moisture and conductive dust.
• Record recurring E.PE faults to monitor EEPROM health.
• Replace aging control boards showing repeated memory-related faults.
• Verify parameter retention during scheduled preventive maintenance.

Proper management of EEPROM write operations, appropriate use of Pr.342 (RAM Write), regular parameter backups, and inspection of the control circuit board will help prevent recurring E.PE Parameter Storage Device Faults in Mitsubishi FR-E700 drives, ensuring reliable parameter storage, dependable drive operation, and extended control board service life.