Fuji Electric FRENIC MEGA G2 Series - Page 634

6.3 If an Alarm Code Appears on the LED Monitor
6-20
[ 26 ] lok Password protection
Phenomenon: The wrong user password was entered more than the prescribed number of times.
Possible cause
Check and measures
Phenomenon: User password 1 or 2
was entered incorrectly more
than the prescribed number of
times.
Clear the alarm.
➔ Turn OFF the inverter power, and then turn it back ON again.
If you have forgotten your password:
➔ Contact the distributer or machine set manufacturer.
[ 27 ] lU Undervoltage
Phenomenon: DC intermediate circuit voltage has dropped below the undervoltage detection level.
Possible cause
Check and measures
(1) A momentary power failure
occurred.
[Subcode: 1]
[Subcode: 3]
➔ Release the alarm.
➔ If you want to restart running the motor without treating this
condition as an alarm, set F14 to “3,” “4,” or “5,” depending on the
load type.
(2) The power to the inverter was
switched back to ON too soon
(when F14 = 1).
[Subcode: 2]
Check if the power to the inverter was switched back to ON while the
control power was still alive. Check whether the LEDs on the keypad are
lit.
➔ Turn the power ON again after all LEDs on the keypad turn OFF.
(3) The power supply voltage did
not reach the inverter's type
correct range.
Measure the input voltage.
➔ Increase the voltage to within the specified range.
(4) Peripheral equipment for the
power circuit malfunctioned, or
the connection was incorrect.
Measure the input voltage to find which peripheral equipment
malfunctioned or which connection is incorrect.
➔ Replace any faulty peripheral equipment, or correct any incorrect
connections.
(5) Any other loads connected to
the same power supply has
required a large starting current,
causing a temporary voltage
drop.
Measure the input voltage and check the voltage fluctuation.
➔ Reconsider the power supply system configuration.
(6) Inverter's inrush current caused
the power voltage drop because
the power supply transformer
capacity was insufficient.
Check if the alarm occurs when a molded case circuit breaker (MCCB),
earth leakage circuit breaker (ELCB) (with overcurrent protection) or
magnetic contactor (MC) is turned ON.
➔ Reconsider the capacity of the power supply transformer.
[ 28 ] nrb NTC wire break error
Phenomenon: A wire break was detected on the NTC thermistor detection circuit.
Possible cause
Check and measures
(1) The motor thermistor cable is
broken.
Check whether the motor cable is broken.
➔ Replace the cable.
(2) The motor ambient temperature
is low (-30 °C (-22 °F) or below).
Measure the surrounding temperature.
➔ Review the operating environment.
(3) The motor thermistor is
damaged.
Measure the motor thermistor resistance.
➔ Replace the motor.