Adjust the output torque (current) of the motor
A machine protection and load limit by torque limit (Pr. 277)
When Pr. 277 "Stall prevention current switchover" = 1, torque limit can be set.
When output torque (torque current) exceeds the stall prevention operation level, the output fre-
quency is controlled to limit the output torque. For the stall prevention operation level at this time,
the motor rated torque is defined as reference.
When driving multiple motors with one inverter, torque limit does not function properly.
Since magnetic flux decreases in the constant output range (Pr. 3 "Base frequency" or
more), the inverter operate with lower torque than the stall prevention operation level.
When torque limit is activated during regeneration, the output frequency is increased up to
the maximum frequency.
Torque limit does not function at 5Hz or less during deceleration.
Note the following when using torque limit under V/f control.
Capacity of the inverter and motor should be the same.
Stall prevention operation level (torque limit level) is the rated torque reference of the motor
whose capacity is equivalent to the inverter.
When Pr. 0 "Torque boost" setting is large, torque limit is likely to occur in the low speed
Use the advanced magnetic flux vector control when more appropriate torque limit is
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