Protective and Diagnostic Functions
7-
7
OL2
Inv Over-
loaded
Inverter Overload
The Inverter overload protection func-
tion has operated based on the internal
electronic thermal value.
The load is too heavy. The accelera-
tion time, deceleration time and cycle
time are too short.
Check the size of the load and the
length of the acceleration, deceler-
ation, and cycle times.
The constant setting for speed search
is incorrect.
(Motor overload occurred due to
motor hunting and vibration.)
• Use the speed search function.
• Adjust the settings of the Speed
search operating current (b3-02)
and Speed search deceleration
time (b3-03).
• Use the estimated speed search
function. (Perform stationary
autotuning for line-to-line resis-
tance only.)
The directions of the motor and PG
are different. (Only in flux vector con-
trol)
• Correct the PG wiring.
• Correct the motor wiring.
• Change the setting of PG rota-
tion (F1-05).
The V/f characteristics voltage is too
high.
Check the V/f characteristics.
The Inverter capacity is too low.
Replace the Inverter with one that
has a larger capacity.
• A short-circuit bV,
−
V, and
AC terminals occurred.
• Overload in the control circuit ter-
minal.
• Make sure that incorrect wiring
has not been done.
• Check the resistance and wir-
ing for the frequency setting
potentiometer, etc. (Check that
the current for terV and
–V is 20 mA or less.)
Inverter overload occurred when run-
ning at a low speed of 6 Hz or less.
• Reduce the load.
• Increase the frame size of the
Inverter.
• Lower the carrier frequency.
OL3
Overtorque
Det 1
Overtorque Detected 1
There has been a current greater than
the setting in L6-02 for longer than the
setting in L6-03.
-
• Make sure that the settings in
L6-02 and L6-03 are appropri-
ate.
• Check the mechanical system
and correct the cause of the
overtorque.
OL4
Overtorque
Det 2
Overtorque Detected 2
There has been a current greater than
the setting in L6-05 for longer than the
setting in L6-06.
-
• Make sure that the current set-
ting in L6-05 and time setting in
L6-06 are appropriate.
• Check the mechanical system
and correct the cause of the
overtorque.
OL7
HSB-OL
High-slip Braking OL
The output frequency did not change
for longer than the time set in N3-04.
The inertia returned to the load is too
large.
• Make sure the load is an inertial
load.
• Set the system so that the decel-
eration time that does not pro-
duce overvoltages is 120 s or
less.
Table 7.1 Fault Displays and Processing (Continued)
Display
Meaning
Probable Causes
Corrective Actions