Mitsubishi Electric MELSEC-L LD75D, User Manual

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(4) Control precautions
• When limiting the torque at the "[Pr.17] Torque limit setting value", confirm that "[Cd.22] New torque value" is
set to "0". If this parameter is set to a value besides "0", the "[Cd.22] New torque value" will be validated, and
the torque will be limited at that value. (Refer to

Page 557, Section 12.5.4 for details about the "new
torque value".)
• When "[Pr.54] OPR shift amount" exceeds "[Pr.17] Torque limit setting value", the error "OPR torque limit
value error" (error code: 995) will occur.
• When the operation is stopped by torque limiting, the droop pulse will remain in the deviation counter. If a
"deviation counter clear" is carried out by issuing an external signal at this time, positional deviation will
occur when the operation is continued. If the load torque is eliminated, operation for the amount of droop
pulses will be carried out.
(5) Setting method
• To use the "torque limit function", set the "torque limit value" in the parameters shown in the following table,
and write them to the LD75. The set data is made valid on the rising edge (OFF to ON) of the PLC READY
signal [Y0].
Refer to  Page 118, Section 5.2 for the information on detail settings.
The following table shows the "[Md.35] Torque limit stored value" of the buffer memory address.
Refer to

Page 182, Section 5.6 for the information on detail settings.
Remark
● Parameters are set for each axis.
●
It is recommended that the parameters be set whenever possible with GX Works2. Execution by program uses many
programs and devices. The execution becomes complicated, and the scan times will increase.
Setting item
Setting
value
Setting details Factory-set initial value
[Pr.17]
Torque limit setting
value

Set the torque limit value as a percentage. 300
[Pr.54]
OPR torque limit
value

Set the torque limit value after the "[Pr.47] Creep speed" is reached.
Set as a percentage.
300
Monitor item
Monitor
value
Storage details
Buffer memory address
Axis 1 Axis 2 Axis 3 Axis 4
[Md.35]
Torque limit stored
value

The "torque limit value" valid at that time is stored. ([Pr.17]
or [Pr.54] or [Cd.22])
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