Mitsubishi FR-A740-00023-EC, Инструкция по эксплуатации

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98
Speed control by real sensorless vector
control, vector control
(9) Alarm stop when torque limit is activated ( Pr. 874 )
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This function can make an alarm stop if the torque limit is
activated to stall the motor.
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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.
REMARKS
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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.
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Parameters referred to
♦
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Pr. 22 Stall prevention operation level Refer to page 144
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Pr. 178 to Pr. 189 (input terminal function selection) Refer to page 222
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Pr. 840 Torque bias selection Refer to page 108
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Pr. 865 Low speed detection Refer to page 237
Output torque
Output
frequency
Start
signal
(STF)
Alarm
contact
Pr. 874
Torque limit
Pr. 865
3s
Torque
Time
Time
E.OLT occurrence