Mitsubishi FR - S500 Instruction Manual page 151

(3) Warnings
Operation Panel Indication
Name
Description
Check point
Corrective action
*4. The stall prevention operation current can be set as desired. It is factory-set to
150%.
Operation Panel Indication
Name
Description
Check point
Corrective action
OL
Stall prevention (overcurrent)
If a current of more than 150% (* 4) of the rated
inverter current flows in the motor, this function
stops the increase in frequency until the overload
During
current reduces to prevent the inverter from
acceleration
resulting in overcurrent shut-off. When the
overload current has reduced below 150%, this
function increases the frequency again.
If a current of more than 150% (* 4) of the rated
inverter current flows in the motor, this function
During
lowers the frequency until the overload current
constant-
reduces to prevent overcurrent shut-off. When the
speed
overload current has reduced below 150%, this
operation
function increases the frequency up to the set
value.
If a current of more than 150% (* 4) of the rated
inverter current flows in the motor, this function
stops the decrease in frequency until the overload
During
current reduces to prevent the inverter from
deceleration
resulting in overcurrent shut-off. When the
overload current has reduced below 150%, this
function decreases the frequency again.
Check the motor for use under overload.
The acceleration/deceleration time may change.
Increase the stall prevention operation level with Pr. 22 "stall
prevention operation level", or disable stall prevention with
Pr. 21 "stall prevention function selection".
Check that the torque boost (Pr. 0) setting is not higher than
required.
oL
Stall prevention (overvoltage)
If the regenerative energy of the motor increases
too much to exceed the brake capability, this
During
function stops the decrease in frequency to prevent
deceleration
overvoltage shut-off. As soon as the regenerative
energy has reduced, deceleration resumes.
Check for sudden speed reduction.
The deceleration time may change. Increase the deceleration
time using Pr. 8 "deceleration time".
142
FR-PU04 OL
FR-PU04 oL
3