Application 1: Safety Mode Sil2/Cat.3/Pld And Application 2: Safety Mode; Sil3/Cat.4/Ple - Siemens S7-300 Installation And Operating Manual

8.5.3

Application 1: Safety Mode SIL2/Cat.3/PLd and application 2: Safety mode

SIL3/Cat.4/PLe

Introduction
Below are the wiring scheme and the parameter assignment of SM 326;
DO 8 x DC 24V/2A PM for
● application 1: Safety mode SIL2/Cat.3/PLd
● Application 2: Safety mode SIL3/Cat.4/PLe
Diagnostic messages, possible causes of the problem and their corrective measures are
found in tables in the chapter "Diagnostic messages of SM 326; DO 8 x DC 24V/2A PM
(Page 133)".
Wiring scheme of applications 1 and 2
Each one of the 8 fail-safe digital outputs consists of one DOx P-switch (current source) and
one DOx M-switch (current consumer); connect the load between the P and M switches.
Figure 8-37
Fail-safe signal modules
Installation and Operating Manual, 01/2010, A5E00085586-10
Wiring scheme of the SM 326; DO 8 x DC 24V/2A PM for applications 1 and 2
Digital modules
8.5 SM 326; DO 8 x DC 24V/2A PM
131