6 FUNCTIONAL SAFETY
6.4 Safety sub-function
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6
Stop monitoring
The SOS function monitors both the command speed and feedback speed.
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Speed command monitoring
During stop monitoring, this function monitors whether the absolute value of the command speed is within the value set in [Pr.
PSA04 Safety sub-function - Stop speed]. If the time of the speed command remains exceeded for the duration set in [Pr.
PSA15 Safety sub-function - Speed detection delay time], the STO function is activated.
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Speed feedback monitoring
During stop monitoring, this function monitors whether the absolute value of the speed feedback is within the value set in [Pr.
PSA04 Safety sub-function - Stop speed]. If the time of the speed feedback remains exceeded for the duration set in [Pr.
PSA15 Safety sub-function - Speed detection delay time], the STO function is activated.
0 r/min
ON
OFF
ON
OFF
Servo motor speed
SS2C (SS2 command)
ON (disabled)
OFF (enabled)
ALM (malfunction)
ON (disabled)
OFF (enabled)
Base circuit
(energy supply to
servo motor)
STOS (STO output)
OFF (shut-off)
SOSS (SOS output)
Stop monitoring (SOS)
Feedback
STO state
Deceleration
Stop speed
Speed detection delay time
ON (monitoring)
Command
0 r/min
ON
OFF
ON
OFF
Servo motor speed
SS2C (SS2 command)
ON (disabled)
OFF (enabled)
ALM (malfunction)
ON (disabled)
OFF (enabled)
Base circuit
(energy supply to
servo motor)
STOS (STO output)
OFF (shut-off)
SOSS (SOS output)
Stop monitoring (SOS)
Feedback
STO state
Deceleration
Stop speed
Speed detection delay time
ON (monitoring)
Command