Torque Limit Function (All Operating Modes) - Omron R88M-W User Manual

Operation
• If controlling the position without adding a position control loop, the position may slip due to tempera-
ture drift from the A/D converter, etc. In this case, when MING (gain reduction) is input, the speed loop
gain will fall, and the amount of drift will be lowered. If there is static friction on the load (5% min. of the
rated torque), the Servomotor may stop completely.
• Inputting MING during parts insertion operations after positioning is completed with a position loop
incorporated will make parts insertion easier by weakening resistance to external force.
• This is also effective for operating at high gain during rotations, and for lowering gain to suppress
vibrations when the Servomotor is stopped.
Note If MING is input with applications that include vertical axes with gravity loads or continuous exter-
nal force, the target position cannot be attained.
H Parameters Requiring Setting
Parameter Parameter name
No.
Pn50A.2 Input signal
selection 1: MING
signal selection
Note If changing the default setting, set Pn50A.0 (input signal selection mode) to 1 (user-defined set-
tings).

4-5-10 Torque Limit Function (All Operating Modes)

H Functions
• The torque limit function limits the Servomotor's output torque.
• This function can be used to protect the Servomotor and mechanical system by preventing excessive
force or torque on the mechanical system when the machine (moving part) pushes against the work-
piece with a steady force, such as in a bending machine.
• There are four methods that can be used to limit the torque (pin No. is allocated at the factory):
• Limit the steady force applied during normal operation with user parameters Pn402 (forward
torque limit) and Pn403 (reverse torque limit). (All operation modes.)
• Limit operation with external signals connected to pins CN1-45 (PCL: forward current limit input)
and CN1-46 (NCL: reverse current limit input). Set user parameters Pn404 (forward rotation ex-
ternal current limit) and Pn405 (reverse rotation external current limit) (all operation modes).
• Limit normal operation with analog voltage using TREF (torque command input) as the analog
current limit input (position, speed, internally-set speed limit).
• Limit analog voltage with external signals connected to pins CN1-45 (PCL: forward current limit
input) and CN1-46 (NCL: reverse current limit input) using TREF (position, speed, internally-set
speed limit).
• When torque limit is ON, CLIMT (current limit detection) signal is output (if the signal has been allo-
cated using parameter Pn50F.0).
• If multiple torque limits are enabled, the output torque is limited to the minimum limit value.
Explanation
Be sure to allocate MING. (See note.)
Chapter 4
Reference
4-4-3 Important
Parameters
4-91