Digital modules
8.3 SM 326; DI 24 x DC 24V
Fail-safe signal modules
82
Installation and Operating Manual, 01/2010, A5E00085586-10
8.3.2
Use cases for the SM 326; DI 24 24V DC
Selecting the application
The figure below helps you to select an application based on availability and fail-safe
operation requirements. The next pages provide information on the module wiring for a
specific application, and on the parameters to set in
STEP 7 using the S7 Distributed Safety
or
S7 F Systems optional package.
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Figure 8-6
SM 326; DI 24 x DC 24V - Selecting an application
WARNING
The maximum Safety Integrity Level is determined by the sensor quality and the length of
the proof-test interval to IEC 61508. Always wire sensors whose quality does not meet
Safety Integrity Level requirements redundantly to two channels.
Note
You can define 1oo1 and 1oo2 sensor evaluation for a module (for example, see table
SM
326; DI 24 x DC 24V: Example of channel configuration in the chapter Properties, front View,
wiring diagram and block diagram).