Ssm Function - Mitsubishi Electric MELSERVO-J5 Series User Manual

SSM function

Outline
This function outputs signals when the servo motor speed is below the prescribed speed.
Operation sequence
■SSMS (SSM output)
In the SSM function, SSMS (SSM output) is on when both the speed command and speed feedback are equal to or less than
the speed set in [Pr. PSA18 SSM speed]. This function monitors whether the absolute value of the speed command and the
absolute value of the speed feedback are within the SSM speed.
Upon detection that either exceeds the SSM speed, SSMS (SSM output) is turned off.
If both the absolute value of the speed command and the absolute value of the speed feedback are lower than the SSM
speed by the amount set in [Pr. PSA19 SSM hysteresis width], SSMS (SSM output) is turned on. By properly setting [Pr.
PSA19], chattering of SSMS (SSM output) can be prevented when the servo motor speed fluctuates in the vicinity of the SSM
speed.
Servo motor speed
SSMS (SSM output)
Setting functional safety parameters
When using the SSM function, set the following parameters.
Parameter
PSA18
PSA19
■SSM speed
Refer to the operation sequence and set the speed threshold for speed monitoring.
■SSM hysteresis width
Refer to the operation sequence and set the hysteresis width needed to prevent SSMS (SSM output) chattering.
6 FUNCTIONAL SAFETY
374
6.4 Safety sub-function
SSM speed
Command
0 r/min
(mm/s)
ON
OFF
Name
SSM speed
SSM hysteresis width
Feedback
SSM hysteresis width