Siemens SIMATIC ET 200AL System Manual page 139

Safety-related communication
Communication used to exchange fail-safe data.
SELV
Safety Extra Low Voltage = Safety extra-low voltage
Sensor evaluation
There are two types of sensor evaluation:
→ 1oo1 evaluation – sensor signal is read once
→ 1oo2 evaluation – sensor signal is read in twice by the same F-module and compared
internally
Sensors
Sensors are used for the accurate detection of routes, positions, velocities, rotational speeds,
masses, etc. in the form of digital and analog signals.
Standard mode
Operating mode of F-I/O in which standard communication is possible by means of → safety
frames, but not → safety-related communication.
ET 200AL fail-safe modules are only designed for safety mode.
TIA Portal
Totally Integrated Automation Portal
The TIA Portal is the key to the full performance capability of Totally Integrated Automation.
The software optimizes operating, machine and process sequences.
Value status
Binary additional information for an input signal. This additional information indicates
whether or not the input signal is valid. Example: The value of the input signal is invalid if
wire break has been detected or flutter monitoring has responded. In this case, exception
handling is triggered in an automation function (e.g. with safe substitute value).
Distributed I/O system
System Manual, 08/2021, A5E31861578-AJ
Glossary
137