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4.4 Protection function list
4.4.1 Protection function
Name
Description
Display of
digital panel
･
digital
operator
Display of remote
operator/
Copy unit ERR1
***
At constant
Speed
OC. Drive
On
deceleration
speed
OC. Decel
On acceleration
speed
OC. Accel
Over-current protection
Motor is restricted and decelerates
rapidly, excessive current is drawn
through the inverter and there is a
risk of damage. Current protection
circuit operates and the inverter
output is switched off.
Other
Over. C
Overload protection (note 1)
When the Inverter detects an overload in the motor,
the internal electronic thermal overload operates and
the inverter output is switched off.
Over. L
Braking resistor overload
Protection
When BRD exceeds the usage ratio of the
regenerative
braking resistor, the over-voltage circuit operates and
the inverter output is switched off.
OL. BRD
Over-voltage protection
When regenerative energy from the motor exceeds
the maximum level, the over-voltage circuit operates
and the inverter output is switched off.
Over. V
EEPROM error (note 2)
When EEPROM in the inverter is subject to radiated
noise or unusual temperature rises, the inverter
output is switched off.
EEPROM
Under-voltage
When the incoming voltage of inverter is low, the
control
circuit can’t operate correctly. The under-voltage
circuit operates and the inverter output is switched
off.
Under. V
CT error
When an abnormality occurs to a CT (current
detector) in the inverter, the inverter output is
switched off.
CT
CPU error
When a mistaken action causes an error to the built-
in CPU, the inverter output is switched off.
CPU
External trip
When a signal is given to the EXT intelligent input
terminal, the inverter output is switched off.
(on external trip function select)
EXTERNAL
USP error
This is the error displayed when the inverter power is
restored while still in the RUN mode.
(Valid when the USP function is selected)
USP
Ground fault protection
When power is turned ON, this detects ground faults
between the inverter output and the motor.
GND. Flt
Incoming over-voltage
protection
When the incoming voltage is higher than the
specification value, this detects it for 100 seconds
then the over-voltage circuit operates and the inverter
output is switched off.
OV. SRC
Temporary power loss
protection
When an instantaneous power failure occurs for more
than 15ms, the inverter output is switched off. Once
the instantaneous power failure wait time has elapsed
and the power has not been restored it is regarded as
a normal power failure.
However, when the operation command is still ON
with restart selection the inverter will restart. So
please be careful of this.
Inst. P-F
Abnormal temperature
When main circuit temperature raises by stopping of
cooling fan, the inverter output is switched off.
OH. FIN
Gate Array error
Communication error between CPU and gate array
indicate
GA
Open-phase protection
When an open-phase on the input supply occurs the
inverter output is switched off.
PH. Fail
IGBT error
When an instantaneous over-current is detected on
the output the inverter output is switched off to protect
the main devices.
IGBT
Chapter 4 Explanation of function
