68
3-1
Fault Display
3-1-1
Protection Functions
Protection function
Explanation
Monitor
display
Fault con-
tact output
Low
voltage
protection
Main
circuit
voltage
low
When the Inverter power voltage drops, torque
becomes insufficient and motor is overheated. Inverter
output is stopped when the main circuit DC voltage
becomes lower than the low voltage detection level for
15 ms or longer.
Detection level: approximately 210 V or less
(200 V, 3-phase)
approximately 170 V or less
(200 V, single-phase)
approximately 420 V or less
(400 V, 3-phase)
uU1
(UV1)
Operation
Overcurrent
protection
The Inverter output is shut-off when the Inverter output
current becomes approx. 200% and above of Inverter
rated current.
%c
(OC)
Operation
Ground-fault
protection
The Inverter output is shut-off when a ground-fault
occurs at the Inverter output side.
gf
(GF)
Operation
Overvoltage
protection
The Inverter output is shut-off when the main circuit
DC voltage becomes excessive because of regenera-
tion energy caused by motor deceleration and negative
load.
Detection level: approx. 410 V or more (200 V class)
approx. 820 V or more (400 V class)
%U
(OV)
Operation
Fuse blown
The Inverter output is shut-off when the main circuit
transistor fails.
The fuse clears to prevent wiring from being damaged
by the short-circuit current.
(Not displayed)
Non opera-
tion
Cooling fin overheat
The Inverter output is shut-off when the ambient tem-
perature rises and the heat sink fin reaches 90
°
C.
Please check for a defective cooling fan or clogged
filter.
%h
(OH)
Operation
Overload
protection
Motor
Inverter output is stopped when motor overload is
detected by the electronic thermal overload in the
Inverter. Either a Inverter duty constant-torque special-
ized motor or general-purpose motor can be selected.
If more than one motor is drive, overload protection
should be disabled. Use a thermal relay or thermal pro-
tector for each motor.
%l1
(OL1)
Operation
Inverter
The Inverter output is shut-off when electronic thermal
overload reaches or exceeds the inverse time limit of
112% of the Inverter’s rated current occurs. Maximum
rated overload: 150%, 1 min.
%l2
(OL2)
Operation
Over
torque
detection
The motor operates according to a preset mode when
the Inverter output current exceeds the overtorque
detection level. This function is used to protect the
machine or to monitor the output torque.
%l3
(OL3)
Operation
External fault signal
input
When an external alarm signal is input, the Inverter
operates according to a preset stop method (coasting
to a stop, or ramp to stop)
ef4
(EF4)
ef5
(EF5)
Operation
Control circuit fault
thermistor fault
The Inverter output is shut-off when a transmission
error occurs in the control circuit or a component fails.
cpf00
to
cpf05
*
(see note)
Operation
Note
* indicates the content of Digital Operator display
Fault Display
Section 3-1
