5-1
Chapter 5 TROUBLESHOOTING
5.1 Alarm Codes
Table 5.1 Quick List of Alarm Codes
Code
Name
Description
OC1
OC2
OC3
Instantaneous overcurrent
The inverter momentary output current exceeded the
overcurrent level.
OC1: Overcurrent during acceleration
OC2: Overcurrent during deceleration
OC3: Overcurrent during running at a constant speed
EF
Ground fault
Zero-phase current caused by ground fault in the output
circuit has exceeded the allowable limit.
(30kW or above)
OV1
OV2
OV3
Overvoltage
The DC link bus voltage exceeded the overvoltage
detection level.
OV1: Overvoltage during acceleration
OV2: Overvoltage during deceleration
OV3: Overvoltage during running at a constant speed
LV
Undervoltage
The DC link bus voltage dropped below the undervoltage
detection level.
Lin*
Input phase loss
An input phase loss occurred or the Interphase voltage
unbalance rate was large.
OPL*
Output phase loss
An output phase loss occurred.
OH1
Heat sink overheat
The temperature around the heat sink has risen
abnormally.
OH2
External alarm
The external alarm
THR
was entered.
(when the
THR
"Enable external alarm trip" has been
assigned to any digital input terminal)
OH3
Inverter internal overheat
The temperature inside the inverter has exceeded the
allowable limit.
OH4
Motor protection (PTC/NTC thermistor)
The temperature of the motor has risen abnormally.
OH6
Charging resistor overheat
The temperature of the charging resistor inside the
inverter has exceeded the allowable limit.
DBH
Braking register overheat
The temperature of the Braking resistor has exceeded
the allowable limit.
OL1
Overload of motor 1
The electronic thermal protection for motor overload
detection was activated.
OLU
Inverter overload
The temperature inside the IGBT has risen abnormally.
DBA*
Braking transistor broken
Detection of an abnormality in the brake transistor
Er1
Memory error
An error has occurred when writing data to the inverter
memory.
Er2
Keypad communications error
A communications error has occurred between the
keypad and the inverter.
Er3
CPU error
A CPU error or LSI error has occurred.
Er4
Option communications error
A communications error has occurred between the
connected option card and the inverter.
Er5
Option error
An error was detected by the connected option card (not
by the inverter).
Er6
Operation protection
An incorrect operation was attempted.
Er7
Tuning error
Auto-tuning or Magnetic Pole Position Offset tuning has
failed, resulting in abnormal tuning results.
Er8
ErP
RS-485 communications error
(Er8: RS-485 port 1, ErP: port 2)
A communications error has occurred during RS-485
communication.
ErF
Data saving error during undervoltage
When the undervoltage protection was activated, the
inverter failed to save data, showing this error.
ErH
Hardware error
The LSI on the power printed circuit board has
malfunctioned due to noise, etc.