2 Description of the safety function STO
12 Festo – GDCP-CMMS-AS-G2-S1-EN – 1306NH – English
2.2 Function and application
The CMMS-A S-...-G2 motor controller exhibits the following safety-related features:
– “Safe Torque Off” function (STO),
– Potential-free acknowledgement contact for the operating status,
The function “Safe Stop 1” (SS1) can be achieved with a suitable external safety switching device and
appropriate circuitry of the motor c ontroller CMMS-AS-...-G2.
Safety function
Requirements of the safety switching
device
1)
Switch-off behaviour Stop
categor y
STO Safe
Torque Off
– 2 safety contacts non-delayed
– Connection option for safety
command devices, e.g. emergency
stop switch, protective door switch,
light curtains, etc.
0
SS1 Safe Stop 1 – 1 safety contact non-delayed
– 2 safety contacts relapse delayed
– Connection option for safety
command devices, e.g. emergency
stop switch, protective door switch,
light curtains, etc.
1
1) Or comparable safety switching device with corresponding safety contacts
Tab. 2.1 Selection of the safety function