Festo Контроллер двигателя CMMD-AS - Manual (Page 86)

4. Functional safety engineering
86 Festo P.BE-CMMD-AS-HW-EN 1002NH
4.2.5 Testing the safety function STO
For each on-off cycle of the machine, the PILZ device PNOZ X2P checks whether the relays
of the safety equipment open and close properly.
The function of switching off the output stage enable must be checked regularly
(e.g. monthly) via the PLC.
4711d_21
Fig. 4.5 Block diagram STO
Caution
If the STO function is not required, pins 1 and 2 of [X3.1/2] must be
bridged.
A second channel is required for the STO function as per EN 61508 SIL 2, i.e. a restart
must be reliably prevented via two separate, completely independent paths. These two
paths for interrupting the power supply supply to the drive with the reliable impulse block
are called switch-off paths:
2