User`s manual

7-3
7
UV1
DC Bus Undervolt
DC Bus Undervoltage
The DC bus voltage is below the
Undervoltage Detection Level
(L2-05). The default settings are:
200V class: 190 VDC
400 V class: 380 VDC
The voltage fluctuations of the
power supply are too high.
Check the input voltage.
A momentary power loss
occurred.
The terminal screws of the input
power supply are loose.
Check the wiring of the input
terminals.
An open-phase error occurred at
the input terminals.
Check the input voltage and
the wiring of the input termi-
nals.
The acceleration time is set too
short.
Extend the settings in
C1-01/03/05/07
Main Circuit MC
Operation Failure
The MC stopped responding dur-
ing Inverter operation. (Applica-
ble Inverter Capacities
200 V class: 37 to 110 kW
400 V class: 75 to 300 kW)
An error occurred in the inrush
current prevention circuit while
the Inverter was running.
Replace the Inverter.
UV2
CTL PS Undervolt
Control Power Supply
Undervoltage
Undervoltage of the control cir-
cuit while the Inverter was run-
ning.
External load was pulling down
the Inverter’s power supplies or
there was an internal short in the
power/gate drive board.
Remove all connection to the
control terminals and cycle the
power to the Inverter.
Replace the Inverter.
UV3
MC Answerback
Inrush Current Prevention Circuit
Fault
An overheating of the charging
resistor for the DC bus capacitors
occurred.
The MC of the charging circuit
did not respond 10 sec. after the
MC ON signal has been output.
(Applicable Inverter Capacities
200 V class: 37 to 110 kW
400 V class: 75 to 300 kW)
The contactor of the inrush cur-
rent prevention circuit is defec-
tive.
Cycle the power to the
Inverter.
Replace the Inverter if the
fault continues to occur.
PF
Input Phase Loss
Main Circuit Voltage Fault
An unusual big ripple on the DC
bus voltage has been detected.
Only detected when L8-05=1
(enabled)
The wiring terminals for the input
power supply are loose.
Tighten the input terminal
screws
A phase loss occurred in the input
power supply.
Check the power supply volt-
age
A momentary power loss
occurred
The voltage fluctuations in the
input power supply are too high.
The voltage balance between the
input phases is bad.
LF
Output Phase Loss
Output Open-phase
An open-phase occurred at the
Inverter output.
The fault is detected when the
output current falls below 5% of
the inverter rated current and L8-
07=1 (enabled)
There is a broken wire in the out-
put cable.
There is a broken wire in the
motor winding.
The output terminals are loose.
Reset the fault after correct-
ing its cause.
The motor being used has a
capacity less than 5% of the
Inverter's maximum motor capac-
ity.
Check the motor and Inverter
capacity.
Table 7.1 Fault Detection
Display Meaning Probable Causes Corrective Actions