Problems and Solutions

OH2 (002E) - External Thermal Trip:
+ A thermal trip command is received from an external input device.
+ Check the external input device.

Ot (0020) - Over-Torque Trip:
+ The load torque exceeds the over-torque detection level during operation.
+ Enable F515 (over-torque trip selection).
+ Check if the system is in a normal condition.

OLr (000F) - Dynamic Braking Resistor Overload Trip:
+ The deceleration time is too short.
+ The dynamic braking amount is too large.
+ Increase the deceleration time.
+ Use a dynamic resistor with a larger capacity and adjust F308 (PBR capacity parameter) accordingly.

OH (0010) - Overheat:
+ The cooling fan does not rotate.
+ The ambient temperature is too high.
+ The vent is blocked.
+ A heat-generating device is installed close to the inverter.
+ The thermistor in the unit is broken.
+ Restart the operation by resetting the inverter after it has cooled down enough.
+ The fan requires replacement if it does not rotate during operation.
+ Ensure sufficient space around the inverter.
+ Do not place any heat-generating device near the inverter.
+ Make a service call.

UP1 (001E) - Undervoltage Trip (Main Circuit):
+ The input voltage in the main circuit is too low.
+ Check the input voltage.
+ Enable F627 (undervoltage trip selection).
+ Use F302 (ride-through control) and F301 (auto-restart) to cope with momentary stops due to undervoltage.

UC (001D) - Small-Current Operation Trip:
+ The output current falls below the low-current detection level during operation.
+ Enable F510 (low-current detection parameter).
+ Check whether the detection level is set properly to the system (check F511 and F512).
+ If no error is found in the setting, make a service call.

EF2 (0022) - Ground Fault Trip:
+ A ground fault occurs in the output cable or the motor.
+ Check the cable and the motor for ground faults.

E (0011) - Emergency Stop:
+ During automatic operation or remote operation, a stop command is received from the operation panel or a remote input device.
+ Reset the inverter.

Err1 (0015) - Main Unit RAM Fault:
+ The control RAM is defective.
+ Make a service call.

Err3 (0016) - Main Unit ROM Fault:
+ The control ROM is defective.
+ Make a service call.

Err4 (0017) - CPU Fault Trip:
+ The control CPU is defective.
+ Make a service call.

Err5 (0018) - Remote Control Error:
+ An error arises during remote operation.
+ Check the remote control device, cables, etc.

Etyp (0029) - Inverter Type Error:
+ The control circuit board (main circuit board or drive circuit board) is replaced.
+ Make a service call.

EEP1 (0012) - EEPROM Fault:
+ A data writing error occurs.
+ Turn off the inverter, then turn it on again. If the error persists, make a service call.

Etun (0028) - Auto-Tuning Error:
+ Check the settings of the motor parameters (F401 to F403).
+ Check that the motor is not two or more sizes smaller in capacity than the inverter.
+ Check that the inverter output cable is not too long.
+ Check that the motor is not running.
+ Check that the motor is a three-phase inductive motor.

Alarm Information

OFF (Note 1) - ST Terminal OFF:
+ The ST-CC circuit is opened.
+ Close the ST-CC circuit.

nOFF - Undervoltage in Main Circuit:
+ The supply voltage between R, S, and T is under voltage.
+ Measure the main circuit supply voltage. If the voltage is at a normal level, the inverter requires repair.

retry - Retry in Process:
+ The inverter is in the process of retry.
+ A momentary stop occurred.
+ The inverter is normal if it restarts after several seconds. The inverter restarts automatically. Be careful of the machine as it may suddenly restart.

Err1 - Frequency Point Setting Error:
+ The frequency setting signals at points 1 and 2 are set too close to each other.
+ Set the frequency setting signals at points 1 and 2 apart from each other.

Clr - Clear Command Acceptable:
+ This message is displayed when pressing the STOP key while an error code is displayed.
+ Press the STOP key again to clear the trip.

EOFF - Emergency Stop Command Acceptable:
+ The operation panel is used to stop the operation in automatic control or remote control mode.
+ Press the STOP key for an emergency stop. To cancel the emergency stop, press any other key.

HI LO - Setting Error Alarm:
+ An error is found in a setting when data is reading or writing.
+ Check whether the setting is made correctly.

Status Messages and Explanations

db - DC Braking:
        In the process of DC braking.
        It is normal if the message disappears after a few seconds. (See Note 2.)

init - Parameters in the Process of Initialization:
        Parameters are being reset to default values.
        It is normal if the message disappears after several seconds to several tens of seconds.

Ptn - Setup Parameters in the Process of Being Set:
        Setup parameters are in the process of being set.
        It is normal if the message disappears after several seconds to several tens of seconds.

Atn - Auto-Tuning in Process:
        Auto-tuning is in process.
        It is normal if the message disappears after several seconds.

    Note 1: ST: Terminal of the standby function.
    Note 2: When the ON/OFF function is selected for DC braking (DB), using the input terminal selection parameter, you can consider the inverter normal if "db" disappears when opening the circuit between the terminal and CC.

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