Siemens SIMATIC ET 200SP Manual page 104

Glossary
F-address
Each fail-safe module has an F-address. For the F-CM AS-i Safety ST module, the
F-address must initially be assigned online using
configuration.
Fail-safe systems
Fail-safe systems are characterized in that, when certain failures occur, the system remains
in a safe state or changes over directly to another safe state.
F-parameters
The fail-safe parameters are safety-relevant parameters. They are needed for
communication via PROFIsafe.
I-parameters
Individual parameters for revising the AS-i functionality. The I-parameters are safety-
relevant.
LED
A light-emitting diode that is used to display the signal status.
Nibble
A nibble is a unit of information that comprises four bits.
Passivation
When a fail-safe I/O device detects an error, it switches the affected channel, or all channels,
to the safe state. That is, the channels of these fail-safe I/O devices are passivated. The fail-
safe I/O device signals the detected fault to the F-CPU.
In the case of passivation of a fail-safe I/O device with inputs, the fail-safe system provides
the safety program with substitute value "0" instead of the process values that are present at
the fail-safe inputs.
In the case of passivation of a fail-safe I/O device with outputs, the fail-safe system transfers
substitute value "0" to the fail-safe outputs instead of the output values supplied by the safety
program.
PROFIsafe
Safety-related bus profile of PROFINET IO for communication between the safety program
and the fail-safe I/Os in a fail-safe system.
104
Step 7
. You specify the F-address in the
Fail-safe Module F‑CM AS‑i Safety ST (3RK7136‑6SC00‑0BC1)
Manual, 03/2017, A5E03957059020A/RS-AB/002