Application 3: Safety Mode Sil3/Cat.4/Ple - Siemens Simatic S7-1500 Manual

5.4

Application 3: Safety mode SIL3/Cat.4/PLe

Assigning inputs to each other
The digital input module F-DI 16x24VDC has 16 fail-safe inputs, DI
combine two of these inputs each to one input.
You can combine the following inputs:
● DI
● DI
● DI
● DI
● DI
● DI
● DI
● DI
The process signals are provided by channels DI
Wiring
The wiring is carried out on the front connector of the module. Refer to the "Wiring" section in
the S7-1500 Automation System
(http://support.automation.siemens.com/WW/view/en/59191792) system manual.
Sensor supply
The sensor must be supplied internally by at least one channel group for application 3.1.
The sensor can be supplied internally or externally for application 3.2.
Requirements for applications in machine protection with Cat.4
Both conditions must be met for applications in machine protection with Cat.4:
● The wiring between sensors and automation system and between automation system and
actuators must be designed with state-of-the-art engineering and standards to prevent
short-circuits.
● The sensors must be wired as shown in sections Application 3.1 (SIL3/Cat.4/PLe)
(Page 42) or Use case 3.2 (SIL3/Cat.4/PLe) (Page 44). You only need to detect one
short-circuit because 2 faults are required to generate it. This means both signal cables in
short-circuit have an isolation fault. A multiple short-circuit analysis is not required.
Procedures for locating all short-circuits are also permitted if single short-circuits are not
located. One of the two conditions must be met for this purpose:
● Short-circuits may not corrupt the read signals compared to the sensor signals.
● Short-circuits cause a corruption of the read signals compared to sensor signals in the
direction that ensures safety.
See also
Connecting (Page 15)
Digital input module F-DI 16x24VDC (6ES7526-1BH00-0AB0)
Manual, 01/2016, A5E03858068-AA
and DI
0 8
and DI
1 9
and DI
2 10
and DI
3 11
and DI
4 12
and DI
5 13
and DI
6 14
and DI
7 15
Applications of the F-I/O module
5.4 Application 3: Safety mode SIL3/Cat.4/PLe
to DI
0
, DI , DI , DI , DI , DI
0 1 2 3 4
(SIL3). You can
15
, DI and DI .
5 6 7
41