Application 3: Safety Mode Sil2/Cat.3/Pld - Siemens S7-300 Installation And Operating Manual

Digital modules
8.3 SM 326; DI 24 x DC 24V
Parameters
Reaction to
discrepancy error
* Vs does not clock, if the short-circuit test is deactivated.
** There are two digital values in the case of redundant configuration in standard mode; you must
evaluate them in the standard user program.
8.3.5

Application 3: Safety mode SIL2/Cat.3/PLd

Introduction
Below are the wiring scheme and the parameter assignment of the SM 326; DI 24 x DC 24V
digital module for application 3: Safety Mode SIL2/Cat.3/PLd.
Diagnostic messages, possible causes of the problem and their corrective measures are
found in tables in the chapter "Diagnostic messages of SM 326; DI 24 x DC 24V (Page 99)".
Wiring scheme for application 3 with single-channel connection
of one single-channel sensor
One sensor is connected via one channel for each process signal (1oo1 evaluation). The
sensors can also be connected to an external sensor supply.
Figure 8-10
To achieve SIL2/Cat.3/PLd using this wiring, you must use a suitably qualified sensor.
86
Range of values in standard mode
Link signals by logical "AND"

operation
Link signals by logical "OR"

operation
Use last valid value

Wiring scheme of the SM 326; DI 24 x DC 24V for application 3 – one sensor single-
channel connection
WARNING
Type
static
Installation and Operating Manual, 01/2010, A5E00085586-10
Effective range
redundant module
pair
Fail-safe signal modules