Lu Undervolatge Protection; L Input Phase Loss Protection - GE Fuji Electric AF-300 Mini Startup Manual

[3] LU Undervoltage protection
Problem Intermediate dc circuit voltage was below the undervolatge detection level.
Possible Causes
(1) An instantaneous power
failure occurred.
2) The power to the drive
was switched back on
too soon (with F14 = 1)
(3) The power supply voltage
did not reach the range of
the drive's specifications.
(4) Peripheral equipment
for the power circuit
malfunctioned, or the
connection was wrong.
(5) High inrush current of
other loads connected to
the same power system
as the drive caused a
temporary voltage drop.
6) Inrush current caused the
power voltage drop be-
cause power transformer
capacity was insufficient.
[4] L Input phase loss protection
Problem Input phase loss occurred, or rate of unbalance of interphase power voltage was large.
Possible Causes
(1) Main circuit power input
wires broken.
(2) The terminal screws for
the main circuit power
input were not tight
enough.
(3) Interphase unbalance
rate of 3-phase voltage
was too large.
What to Check and Suggested Measures
SUGGESTED ACTIONS
– Reset the alarm.
– To restart running the motor without an alarm, set F14 to a value of 4 or 5 depending on load.
CHECK
Only switch the drive on after the power for the control circuit has reached an appropriate level. This can
be checked using the display on the LED monitor.
SUGGESTED ACTIONS
– Wait longer before switching the drive on.
CHECK
Measure the input voltage.
SUGGESTED ACTIONS
– Increase the voltage to specification.
CHECK
Measure the input voltage to find where the peripheral equipment malfunctioned or which connection is
incorrect.
SUGGESTED ACTIONS
– Replace any faulty peripheral equipment, or correct any wrong connections.
CHECK
Measure the input voltage and check the voltage variation.
SUGGESTED ACTIONS
– Reconsider the power system configuration.
CHECK
Check if the alarm occurs when you switch on a molded case circuit breaker, a ground fault circuit
interrupter (GFCI) or a magnetic contactor.
SUGGESTED ACTIONS
– Reconsider the power transformer rating.
What to Check and Suggested Measures
CHECK
Measure the input voltage.
SUGGESTED ACTIONS
– Repair or replace the wires.
CHECK
Check if the terminal screws have become loose.
SUGGESTED ACTIONS
– Tighten the terminal screws to the recommended torque.
CHECK
Measure the input voltage.
SUGGESTED ACTIONS
– Connect an ac reactor (ACR) or a dc reactor (DCR) to lower the rate.
– Raise the drive capacity.
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