Siemens Sinamics S110 Function Manual page 419

Description
Failsafe digital inputs (F-DI) consist of two digital inputs. The cathode of the optocoupler is
routed to the second digital input in order to allow the connection of an M-switching F-DO
output (the anode must be connected to 24 V DC).
Parameters p10040/p10140 are used to determine whether an F-DI is operated as NC/NC or
NC/NO contact. The status of each DI can be read at parameter r0722. The same bits of
both drive objects are logically linked by AND operation and return the status of the relevant
F-DI (r10051/r10151).
Test signals from controls can be filtered out using parameter p10017/p10117, so that faults
are not incorrectly interpreted.
Explanation of terms:
NC contact / NC contact: To select the safety function, a "zero level" must be present on
both inputs.
NC contact / NO contact: To select the safety function, a "zero level" at input 1 and a "1
level" at input 2 must be present.
The signal states at the two associated digital inputs (F-DI) must assume the same status
configured in p10040/p10140 within the monitoring time set in p10002/p10102.
Figure 8-18 Overview of F-DI 0 ... 2
Function Manual
Function Manual, 01/2011, 6SL3097-4AB10-0BP3
Safety Integrated Functions
8.6 Controlling the safety functions
417