Siemens Simovert Masterdrives Compact Plus Series Operating Instructions Manual page 197

Connecting-up
7-18
All external cables relevant to the safety function are protected, e.g.
installed in cable ducts, to preclude the possibility of short circuits.
Cables must be installed in compliance with the requirements of
EN 60204-1, Section 14.
In the circuit shown in Fig. 7-6, the tumbler does not release the moving
protective device until the drive has stopped. It may be possible to omit
the tumbler if the risk assessment of the machine deems this to be
safe. In this case, the NC contact of the protective device is connected
directly to terminals Y11 and Y12 and electromagnet Y1 is omitted.
Binary input X is negated with signal "OFF3", i.e. at 24 V, the converter
decelerates the motor to zero speed along the parameterized
deceleration ramp. The converter signals zero speed via binary output
Y, thus energizing relay K2.
Once the motor has stopped, the safety relay in the converter is opened
and the coil of main contactor K1 remains at 24 V via the checkback
contact. If contacts in the safety relay are sticking, the checkback
contacts do not close and the safety combination on the right
deenergizes main contactor K1 via delayed contacts 47/48 when the
set delay period expires.
6SE7087-6KP50
Operating Instructions SIMOVERT MASTERDRIVES
06.2006
Siemens AG