70
3-1-2
Warning and Self-diagnosis Functions
Protection function
Explanation
Monitor
display
Fault con-
tact output
Low-voltage protection
(main circuit voltage
insufficient)
Monitor display appears when the main circuit DC
voltage drops under the detection level while the
Inverter output is off.
(UV)
uU
(Blink)
Non
operation
Overtorque detection
This function is used to protect the machine and to
monitor the Inverter’s output torque.
The Inverter output reacts in a preset manner when
the Inverter output current exceeds the over torque
detection level. The monitor display blinks when
“operation continue” is preset.
(OL3)
%l3
(Blink)
Non
operation
Stall pre-
vention
(Accel/decel
is accom-
plished with
maximum
capacity of
the Inverter
During
accelera-
tion
Inverter acceleration is stopped when 170% of or
more of the Inverter rated current is required by the
load.
This prevents overload protection (OL2) or overcur-
rent (OC) from occurring.
When current is reduced to less than 170%, accel-
eration is enabled.
---
Non
operation
the Inverter
without trip-
ping on
overcurrent
or overvol-
tage.)
During nor-
mal opera-
tion
Output frequency is decreased when 160% of the
Inverter rated current or greater is required by the
load. This prevents motor and Inverter overload
(OL1, OL2). When current is reduced below 160%,
Inverter acceleration is then enabled.
During
decelera-
tion
Deceleration is stopped when the DC voltage is
caused to rise by motor regenerative energy.
This prevents overvoltage trips (OV). When DC volt-
age decreases, deceleration to the set value then
resumes.
Simultaneous forward
and reverse rotation com-
mands
When forward and reverse rotation commands are
simultaneously detected for a period of time exceed-
ing 500 ms, the Inverter is stopped according to the
preset stop method.
(EF)
ef
(Blink)
Non
operation
External base block sig-
nal input (main circuit
transistor instantaneous
shut-off)
When an external base block signal is input, the
motor coasts to a stop. When the external base block
signal is removed, the Inverter output is immediately
turned on at the previously set frequency.
(BB)
bb
(Blink)
Non
operation
Fault Display
Section 3-1
