Mitsubishi Electric FR-C500 Instruction Manual page 74

Stall prevention (Pr. 22)
Set the output current level at which the output frequency will be adjusted to
prevent the inverter from stopping due to overcurrent, etc.
Parame
ter
22 Stall prevention operation level
<Setting>
•Generally, set 150% (factory setting) in Pr. 22 "stall prevention operation level".
Setting "0" in Pr. 22 disables stall prevention operation.
CAUTION
•* When "Operation not continued for OL signal output" is selected, the "OLT"
alarm code (stopped by stall prevention) is displayed and operation
stopped.
(Alarm stop display "
•If the load is heavy, the lift is predetermined, or the acceleration/deceleration
time is short, the stall prevention may be activated and the motor not stopped
in the preset acceleration/deceleration time. Therefore, set optimum values to
the Pr. 21 and stall prevention operation level.
•When the fast-response current limit has been set in Pr. 21 (factory setting),
torque will not be provided at the Pr. 22 setting of 170% or higher. At this time,
make setting so that the fast-response current limit is not activated.
•In vertical lift applications, make setting so that the fast-response current limit
is not activated. Torque may not be produced, causing a drop due to gravity.
Do not set a small value as the stall prevention operation current.
Otherwise, torque generated will reduce.
Test operation must be performed.
Stall prevention operation performed during acceleration may increase the
acceleration time.
Stall prevention operation performed during constant speed may cause
sudden speed changes.
Stall prevention operation performed during deceleration may increase the
deceleration time, increasing the deceleration distance.
Name
")
CAUTION
Factory Setting
Setting Range
150% 0 to 200%
65
Basic Functions
3