Glossary
ET 200S Distributed I/O System - Fail-Safe Modules
216 Installation and Operating Manual, 08/2008, A5E00103686-07
PROFIsafe address
Each -> fail-safe module is assigned a separate PROFIsafe address. The PROFIsafe
address must be configured in
STEP 7 HW Config
and set via a switch on the fail-safe I/O.
PROFIsafe monitoring time
Monitoring time for safety-related communication between the F-CPU and F-I/O.
Proof-test interval
Period after which a component must be forced to fail-safe state, that is, it is either replaced
with an unused component, or is proven faultless.
P-switch
-> M-switch
Redundancy, availability-enhancing
Multiple instances of components with the objective of maintaining component functionality in
the event of hardware faults.
Redundancy, safety-enhancing
Multiple installations of components with the goal of reducing hardware faults; for example, -
> 1oo2 evaluation in -> fail-safe modules.
Reintegration
The -> F-I/O must be reintegrated (depassivated) after a fault has been cleared.
Reintegration (switchover from fail-safe values to process values) occurs either automatically
or only after a user acknowledgment in the safety program.
For an F-I/O module with inputs, the process values pending at the fail-safe inputs are again
made available to the -> safety program following reintegration. For an F-I/O module with
outputs, the output values provided by the -> safety program are again made available to the
fail-safe outputs following reintegration.
Response time
The response time starts with the detection of an input signal and ends with the modification
of a logically linked output signal.
The actual response time is between the shortest and the longest response time. The
longest response time must always be anticipated when configuring a plant.
For fail-safe digital inputs: The response time defines the interval between a signal transition
at the digital input and the reliable availability of the -> safety message frame on the
backplane bus.
For fail-safe digital outputs: The response time defines the interval between the receipt of a
safety message frame from the backplane bus and the signal transition at the digital output.
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