Fuji Electric FRENIC-HVAC User Manual page 644

Possible Causes
(4) The activation level (H27) of the
PTC thermistor for motor
overheat protection was set
inadequately.
(5) Settings for the PTC thermistor
are improper.
(6) Excessive torque boost
specified. (F09)
(7) The V/f pattern did not match
the motor.
(8) Incorrect setting of function
code data.
[ 11 ] FUS Fuse blown
Problem The fuse inside the inverter blew.
Possible Causes
(1) The fuse blew due to
short-circuiting inside the
inverter.
[ 12 ] PbF Charger circuit fault
Problem The magnetic contactor for short-circuiting the charging resistor failed to work.
Possible Causes
(1) The control power was not
supplied to the magnetic
contactor intended for
short-circuiting the charging
resistor.
What to Check and Suggested Measures
Check the PTC thermistor specifications and recalculate the detection
voltage.
 Modify the data of function code H27.
Check the setting of the thermistor mode selection (H26) and the slider
position of the terminal [C1] property switch SW5.
 Change the H26 data in accordance with the thermistor used and
set the SW5 to the PTC position.
Check whether decreasing the torque boost (F09) does not stall the
motor.
 If no stall occurs, decrease the F09 data.
Check if the base frequency (F04) and the rated voltage at base
frequency (F05) match the values on the motor's nameplate.
 Match the function code data with the values on the motor's
nameplate.
Although no PTC thermistor is used, the thermistor mode is enabled
(H26).
 Set the H26 data to "0" (Disable).
What to Check and Suggested Measures
Check whether there has been any excess surge or noise coming from
outside.
 Take measures against surges and noise.
 Have the inverter repaired.
What to Check and Suggested Measures
Check that, in normal connection of the main circuit (not a connection
via the DC link bus), the connector (CN R) on the power printed circuit
board (power PCB) is not inserted to NC .
 Insert the connector (CN R) to FAN .
Check whether you quickly turned the circuit breaker ON and OFF to
confirm safety after cabling/wiring.
 Wait until the DC link bus voltage has dropped to a sufficiently
low level and then release the current alarm. After that, turn ON
the power again. (Do not turn the circuit breaker ON and OFF
quickly.)
(Turning ON the circuit breaker supplies power to the control
circuit to the operation level (lighting the LEDs on the keypad) in
a short period. Immediately turning it OFF even retains the control
circuit power for a time, while it shuts down the power to the
magnetic contactor intended for short-circuiting the charging
resistor since the contactor is directly powered from the main
power.
Under such conditions, the control circuit can issue a turn-on
command to the magnetic contactor, but the contactor not powered
can produce nothing. This state is regarded as abnormal, causing
an alarm.)
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