Terms For Fail-Safe Operation - Siemens F IWLAN Operating Instructions Manual

Overview

1.13 Terms for fail-safe operation

1.13 Terms for fail-safe operation
Fail-safe automation system
A fail-safe automation system is required in a plant with high safety requirements.
In an EMERGENCY STOP, the fail-safe automation system brings the plant to a safe
operating state regardless of the situation. Shutdown of the plant therefore does not pose a
danger to people or the plant.
Fail-safe operation
The HMI device registers signals from the EMERGENCY STOP button and the enabling
button during fail-safe operation. The controller and the HMI device communicate via
PROFIsafe.
Configuration of the safety functions in STEP 7 with the "SIMATIC S7 Distributed Safety"
add-on package can achieve fail-safe operation according to SIL 3 or Performance Level e
and Category 4 for the HMI device.
Integration and removal
● Integrating
Integration means to establish safety-related communication between the HMI device and
the fail-safe controller via PROFIsafe.
The EMERGENCY STOP button is enabled in integrated operating mode.
● Removing
Removal means to intentionally stop safety-related communication between the HMI
device and the fail-safe controller via PROFIsafe.
Logging on the HMI device
The HMI device must be logged onto a machine in order to operate the machine after
integration in fail-safe operation with the enabling button. The logon is performed with an
RFID tag.
Logging off an HMI device
Logging off an HMI device from a machine terminates fail-safe operation with the enabling
button.
● Forced logoff
If the security system is triggered, for example by the operator leaving the protection zone
without logging off, a forced logoff is performed by the machine. The HMI device revokes
the operator authorization for the enabling button. The operator is prompted to confirm
the "Forced logoff" dialog.
● Automatic logoff in the event of a communication error
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PRELIMINARY II
Wireless Teach Pendant F IWLAN V2
Operating Instructions, 08/2010, A5E02453837-01
1.7.2010