Festo CMMP-AS-Series-M0-STO, Manual

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2 Description of the safety function STO
Festo – GDCP-CMMP-AS-M0-S1-EN – 1412a – English 11
2.2 Function and application
The CMMP-AS-...-M0 motor controller exhibits the following safety-related features:
– “Safe Torque Off ” function (STO),
– Potential-free acknowledgement contact for the operating status,
By using an appropriate external safety switching device and protective circuit for the CMMP­AS­...­M0
motor controller, the “Safe Stop 1” function (SS1) can be realised.
2.2.1 Description of the safety function STO
Use the “Safe torque off ” function (STO) whenever you have to reliably disconnect the energy supply to
the motor in your particular application.
The “Safe torque off ” function switches off the driver supply for the power semiconductor, thus
preventing the power output stage from supplying the current required by the motor
è
Fig. 2.2.
4
3
5
6
2
1
>=1
dC
dC
STO-A
0V-A
C1
C2
dC
dC
STO-B
0V-B
3x
U, V, W
+VDC
-VDC
DC +24 V
0 V
4
1
Safety command device (e. g. switch, relay,
safety switching device)
2
Integrated safety function STO
3
Power output stage in CMMP-AS-…-M0
(only one phase shown)
4
Driver supply
5
Motor connection
6
Acknowledgment contact
Fig. 2.2 “Safe torque off ” - functional principle for CMMP-AS-…-M0