Mitsubishi Electric FR-A700 EC, Instruction Manual

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Parameter Speed control by real sensorless vector control, vector control
FR-A700 EC 6 - 87
Alarm stop when torque limit is activated (Pr. 874 )
●
This function can make an alarm stop if the torque limit is activated to stall the motor.
●
The motor stalls if the torque limit is activated under a high load applied during speed control
or position control. At this time, if the motor speed is lower than the speed set in Pr. 865
"Low speed detection" and also the output torque exceeds the level set in Pr. 874 "OLT level
setting" for 3s, it is regarded as a stop effected by stall prevention and E. OLT is output,
resulting in an alarm stop.
I001508E
Fig. 6-14: Alarm stop when torque limit is activated
NOTES If the frequency has fallen to 0.5Hz by stall prevention operation and remains for 3s under V/f
control and advanced magnetic flux vector control, an alarm (E.OLT) appears to shutoff the
inverter output. In this case, this function is activated regardless of Pr. 874.
This alarm is not provided under torque control.
Output
frequency [Hz]
Start ignal
STF
Alarm contact
Pr. 865
Pr. 874
Torque
Output torque
Torque limit
3 s
E.OLT occurrence
Time
Time