6-13
Possible Causes
What to Check and Suggested Measures
(5) Any other load(s)
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 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), residual-current-operated protective device (RCD)/earth
leakage circuit breaker (ELCB) (with overcurrent protection) or
magnetic contactor (MC) is turned ON.
Reconsider the capacity of the power supply transformer.
[ 4 ]
lin
Input phase loss
Problem
Input phase loss occurred, or interphase voltage unbalance rate was large.
Possible Causes
What to Check and Suggested Measures
(1) Main circuit power input
wires broken.
Measure the input voltage.
Repair or replace the input wires.
(2) Screws on the main
circuit power input
terminals are loose.
Check if the screws on the inverter input terminals have become
loose.
Tighten the terminal screws to the recommended torque.
(3) Interphase voltage
unbalance between
three phases was too
large.
Measure the input voltage.
Connect an AC reactor (ACR) to lower the voltage unbalance
between input phases.
Raise the inverter capacity.
(4) Overload cyclically
occurred.
Measure the ripple wave of the DC link bus voltage.
If the ripple is large, raise the inverter capacity.
(5) Single-phase voltage
was input to the
three-phase input
inverter.
Check the inverter type.
Apply three-phase power. The FRENIC-Mini of three-phase input
cannot be driven by single-phase power supply.
The input phase loss protection can be disabled with the function code H98 (Protection/
Maintenance Function).