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MELSEC-Q
12 CONTROL SUB FUNCTIONS
12.4.2 Torque limit function
The "torque limit function" limits the generate d torque to a value within the "torque lim it
value" setting range when the torque generate d in the servomotor exceeds the "torque
limit value".
The "torque limit function" protects the deceleration function, l imits the power of the
operation pressing against the stopper, etc. I t controls the operation so that
unnecessary force is not applied to the loa d and machine.
The details shown below explain about the "tor que limit function".
[1] Relation between the torque limit functio n and various controls
[2] Control details
[3] Precautions during control
[4] Setting the torque limit function
[1] Relation between the torque limit function and various controls
The following table shows the relation of the "torque limit function" and various
controls.
Control type Torque limit
function Torque limit value
Machine OPR control
Pr.17 Torque limit setting value
After the " Pr.47 Creep
speed" is reached, this value
becomes the " Pr.54 OPR
torque limit value".
OPR
control
Fast OPR control
1-axis linear control
2 to 4-axes linear
interpolation control
1-axis fixed-feed control
2 to 4-axes fixed-feed
control (interpolation)
Position
control
2-axis circular interpolation
control
1 to 4-axes Speed control
Speed-position switching control
Position-speed switching control
Pr.17 Torque limit setting value
Current value changing –
Major
positioning
control
Other
control JUMP instruction, NOP
instruction, LOOP to
LEND –Setting value is invalid.
JOG operation, Inching operation Pr.17 Torque limit setting value
Manual
control Manual pulse generator operation Pr.17 Torque limit setting value
: Set when req uired (Set to " – " when not used.)
– : Setting not require d (Setting value is invalid. Use the initial values or sett ing values
within a range where no error occurs.)
: Shows the torque limit value when " Cd.22 New torque value" is set to "0".