Siemens SIMATIC ET 200AL, System Manual

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Glossary
Distributed I/O system
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System Manual, 08/2021, A5E31861578-AJ
Passivation
If an → F-I/O module detects a fault it switches either the affected channel or all channels to a
→ safe state, i.e. the channels of this F-I/O module are passivated. The F-I/O module signals
the detected faults to the → F-CPU.
When passivating channels at F-I/O with inputs, the → F-System provides fail-safe values for
the → safety program instead of the process values pending at the fail-safe inputs.
When passivating channels at F-I/O with outputs, the F-system returns fail-safe values (0) to
the fail-safe outputs instead of the output values provided by the safety program.
PELV
P rotective E xtra L ow V oltage = protective extra-low voltage
Performance Level
Performance Level (PL) in accordance with ISO 13849-1 or EN ISO 13849-1
PROFINET
PROcess FIeld NETwork, open Industrial Ethernet standard, which continues PROFIBUS and
Industrial Ethernet. A cross-manufacturer communication, automation and engineering
model, defined as an automation standard by PROFIBUS International e.V.
PROFINET IO controller
Device used to address connected I/O devices (e.g. distributed I/O systems). This means that:
The IO controller exchanges input and output signals with assigned I/O devices. The IO
controller often corresponds with the CPU in which the automation program is running.
PROFINET IO device
Distributed field device that can be assigned to one or more IO controllers (e.g. distributed I/O
system, valve terminals, frequency converters, switches).
PROFINET IO
Communication concept for the realization of modular, distributed applications in the
framework of PROFINET.
PROFIsafe
Safety-oriented PROFINET I/O bus profile for communication between the → safety program
and the → F-I/O module in a → fail-safe system.