Hitachi NE S1 Drive

Hitachi NE S1 Drive Fault Codes:

Fault Code and MeaningCause and Remedy
E01
Over-current event while at constant speed
Cause:

The inverter output was short-circuited, or the motor shaft is locked or has a heavy load. These conditions cause excessive current for the inverter, so the inverter output is turned OFF. The dual-voltage motor may be wired incorrectly.



Remedy:


  • Check for short circuits at the output.

  • Check if the motor shaft is locked or load is too heavy.

  • Verify motor wiring.
E02
Over-current event during deceleration
Cause:

The inverter output was short-circuited, or the motor shaft is locked or has a heavy load. These conditions cause excessive current for the inverter.



Remedy:


  • Check braking requirements or deceleration time.

  • Check for short circuits or mechanical locks.
E03
Over-current event during acceleration
Cause:

The inverter output was short-circuited, or the motor shaft is locked or has a heavy load.



Remedy:


  • Check acceleration time setting.

  • Verify motor wiring and mechanical load.
E04
Over-current event during other conditions
Cause:

The inverter output was short-circuited, or the motor shaft is locked or has a heavy load.



Remedy:


  • General check of output wiring and motor condition.
E05
Overload protection
Cause:

When a motor overload is detected by the electronic thermal function, the inverter trips and turns OFF its output.



Remedy:


  • Reduce motor load.

  • Note: The inverter will not accept any reset command within about 10 seconds after tripping.
E07
Over-voltage protection
Cause:

When the DC bus voltage exceeds a threshold, due to regenerative energy from the motor.



Remedy:


  • Check deceleration time (increase if possible).

  • Check for need of braking resistor.
E08
Memory error
Cause:

When the built-in memory has problems due to noise or excessive temperature, the inverter trips and turns OFF its output to the motor.



Remedy:


  • Turn off the inverter power once.

  • If E08 displays again after power up, the internal memory may have failed.

  • Initialize the inverter and re-set parameters.
E09
Under-voltage error
Cause:

A decrease of internal DC bus voltage below a threshold results in a control circuit fault. This condition can also generate excessive motor heat or cause low torque.



Remedy:


  • Check input power supply voltage.

  • Check for power interruptions.
E10
Current detection error
Cause:

If an error occurs in the internal current detection system, the inverter will shut off its output and display the error code.



Remedy:


  • Check for electrical noise interference.

  • Contact service if error persists.
E11
CPU error
Cause:

A malfunction in the built-in CPU has occurred, so the inverter trips and turns OFF its output to the motor.



Remedy:


  • The inverter will not accept reset commands via RS terminal or keypad.

  • Turn off the inverter power and restart.
E12
External trip
Cause:

A signal on an intelligent input terminal configured as EXT has occurred. The inverter trips and turns OFF the output to the motor.



Remedy:


  • Remove the external trip signal.

  • Reset the inverter.
E13
USP error
Cause:

When the Unattended Start Protection (USP) is enabled, an error occurred when power is applied while a Run signal is present.



Remedy:


  • Ensure Run signal is OFF before powering up.

  • Clear the error to enter Run Mode.
E14
Ground fault protection
Cause:

The inverter is protected by the detection of ground faults between the inverter output and the motor upon during powerup tests.



Remedy:


  • Check motor and cabling for ground faults.

  • Turn off the inverter power to reset (Keypad reset not accepted).
E15
Input over-voltage protection
Cause:

The inverter tests for input over-voltage after the inverter has been in Stop Mode for 100 seconds. An over-voltage condition exists.



Remedy:


  • Check input power supply voltage.

  • After fault is cleared, inverter can enter Run Mode again.
E19
Inverter thermal detection circuit error
Cause:

When the thermal sensor in the inverter module is not connected.



Remedy:


  • Internal hardware check required.
E21
Temperature error
Cause:

When the inverter internal temperature is above the threshold, the thermal sensor detects excessive temperature of power devices.



Remedy:


  • Check cooling fan operation.

  • Check for blocked ventilation or high ambient temperature.
E30
Driver error
Cause:

An internal inverter error has occurred at the safety protection circuit between the CPU and main driver unit. Excessive electrical noise may be the cause.



Remedy:


  • Check for EMC/Electrical noise sources.

  • Turn power off and on.
E34
Output phase loss protection
Cause:

When a phase loss on its outputs is detected, the inverter output is turned off. (Activated only when C157=01).



Remedy:


  • Check output wiring for loose connections.

  • Check motor phases.
E38
Low-speed overload protection
Cause:

If overload occurs during the motor operation at a very low speed, the inverter will detect the overload and shut off the output.



Remedy:


  • Reduce load at low speeds.
E40
Operator connection error
Cause:

When the connection between inverter and operator keypad failed.



Remedy:


  • Check connection between keypad and inverter.
E41
Modbus communication error
Cause:

When “trip” is selected (C076=00) as a behavior in case of communication error, inverter trips when timeout happens.



Remedy:


  • Check Modbus communication lines.

  • Check communication settings.