Siemens SIMATIC ET 200AL, System Manual

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Glossary
PROFIBUS with STEP 7 V13
96
Function Manual, 12/2014, A5E03775446-AC
HSA
Highest Station Address. A bus parameter for PROFIBUS. Outputs the highest PROFIBUS
address of an active device. PROFIBUS addresses greater than HSA are permitted for
passive devices, up to 126.
Industrial Ethernet
Guideline for setting up Ethernet in an industrial environment. The main difference to the
standard Ethernet is the mechanical current carrying capacity and interference immunity of
the individual components.
I-slave
The "I-slave" functionality of a CPU supports the exchange of data with a DP master and can
thus be used, for example, as intelligent preprocessing unit of partial processes. The I-slave
is connected in its role as DP slave to a "higher-level" DP master.
Master
A master device that is in possession of the token can send data to other devices and
request data from them (= active device).
PCF
Polymer Cladded Fiber (plastic-covered glass fiber)
POF
Polymer Optical Fiber (plastic fiber-optic cable made of light-conducting plastics)
Process image
Address area in the system memory of the DP master. At the start of the cyclic program the
signal states of the input modules are transmitted to the process image of the inputs. And the
end of cyclic program execution, the process image of the outputs is transmitted to the DP
slave as signal state.
PROFIBUS
PROcess FIeld BUS, in IEC 61158-2 as "Type 3" standardized, bit-serial fieldbus system.
The standard specifies functional, electrical and mechanical properties.
PROFIBUS is a bus system that networks automation systems and field devices compatible
with PROFIBUS at the cell and field level. PROFIBUS is available with the protocols DP
(= distributed I/O), FMS (= fieldbus message specification) or PA (process automation).