Siemens SIMATIC ET 200M Operating Instructions Manual page 257

Diagnostics
The detection, localization, classification, visualization and further evaluation of errors,
disturbances and messages.
Diagnostics provides monitoring functions which are executed automatically when the
system is in RUN. This increases plant availability by reducing commissioning times and
down times.
Distributed IO devices
are input/output units, set up at a distance from the CPU instead of being used within the
unit. They include:
● ET 200M, ET 200S, ET 200S, ET 200eco
● DP/AS-I Link
● S5-95U with PROFIBUS-DP slave interface
● other Siemens or non-Siemens DP slaves
PROFIBUS DP connects the distributed IO devices to the DP master.
DP master
A → master that performs to the standard IEC 61784-1:2002 Ed1 CP 3/1 is called DP master.
DP slave
A → slave that is operated by the PROFIBUS using the PROFIBUS DP protocol and that
performs to the standard IEC 61784-1:2002 Ed1 CP 3/1 is called DP slave.
DP standard
is the ET 200 distributed I/O system's bus protocol that complies with the standard
IEC 61784-1:2002 Ed1 CP 3/1.
Equipotential bonding
Electrical connection (equipotential bonding conductor) that places electrical equipment parts
and non-equipment related conductive parts at equal or nearly equal potential to prevent
interfering or hazardous voltage between them.
Fault-tolerant system
A fault-tolerant system (also called H system, an abbreviation of the German
'Hochverfügbares System') consists of two or more CPUs or two or more separate devices,
such as PCs (master / reserve). The user program is processed identically in master and
reserve.
ET 200M
Operating Instructions, 12/2008, EWA-4NEB780600602-08
Glossary
255