YASKAWA Varispeed G7 Series Instruction Manual page 423

Display
Main Circuit Undervoltage
The main circuit DC voltage is
below the Undervoltage Detection
Level (L2-05).
200 V Class: Approx. 190 V
400 V Class: Approx. 380 V
UV1
Main Circuit Magnetic Connector
DC Bus
Operation Failure
Undervolt
The magnetic connector stopped
responding during Inverter opera-
tion.
Applicable Inverter Capacities
200 V Class: 30 to 110 kW
400 V Class: 55 to 300 kW
Control Power Fault
UV2
CTL PS The control power supply voltage
Undervolt dropped.
Inrush Prevention Circuit Fault
A fault occurred in the surge pre-
UV3
vention circuit.
MC
The magnetic contactor did not
Answer-
respond for 10 s even though the
back
magnetic contactor ON signal has
been output.
Main Circuit Voltage Fault
The main circuit DC voltage oscil-
lates unusually (not when regener-
PF ating).
Input Pha This fault is detected if a load is
Loss greater than approximately 80% of
the maximum motor capacity.
This fault is detected when L8-05 is
set to 1.
-4
7
Table 7.1 Fault Displays and Processing (Continued)
Meaning
• An open-phase occurred with the
input power supply.
• A momentary power loss occurred.
• The wiring terminals for the input
power supply are loose.
• The voltage fluctuations in the input
power supply are too large.
• A fault occurred in the surge preven-
tion circuit.
• The magnetic contactor in the control
circuit was released (Contact failure
in the auxiliary contact).
• The contact of the magnetic contactor
in the control circuit was corroded
due to environmental dust or gas.
• A fuse on the Change Power Tap Cir-
cuit Board has blown for a 400 V
Class Inverter of 55 kW or higher.
200 V Class power supply
400 V Class power supply
• The wiring of the control power cir-
cuit is incorrect.
• A Backup Capacitor Unit for
Momentary Power Loss is not
attached to a 200 V/400 V Class
Inverter of 7.5 kW or less and the
value of the Momentary power loss
ridethru time (L2-02) factory setting
has been changed to the larger value.
• The magnetic contactor in the main
circuit failed.
• The magnetic contactor excitation
coil is burned out.
• An open-phase occurred in the input
power supply.
• A momentary power loss occurred.
• The wiring terminals for the input
power supply are loose.
• The voltage fluctuations in the input
power supply are too large.
• The voltage balance between phases
is bad.
Probable Causes
Power tap
Jumper
(default position)
Operating power supply
input terminals CHARGE indicator
Corrective Actions
• Reset the fault after correcting
its cause.
• Improve the power supply envi-
ronment. (Check to see if the
correct power tap is selected.)
• Improve the operating environ-
ment.
• Replace the Inverter.
• Try turning the power supply off
and on.
• Replace the Inverter if the fault
continues to occur.
• Attach a Backup Capacitor Unit
for Momentary Power Loss.
• Try turning the power supply off
and on.
• Replace the Inverter if the fault
continues to occur.
Reset the fault after correcting its
cause.