Index - Siemens SIMATIC ET 200SP System Manual

Glossary
AWG (American Wire Gauge)
A standard measure for conductors used in the USA, which is assigned to a specific cross-
sectional area of a conductor or wire. Each AWG number represents a jump of 26% in the
cross-sectional area. The thicker the wire, the smaller the AWG number.
BaseUnit
BaseUnits realize the electrical and mechanical connection of the I/O modules with the
interface module and the server module.
The inserted I/O module determines the signals at the terminals of the BaseUnits.
Depending on the selected BaseUnit, only certain terminals are available.
BaseUnit, dark-colored
Conduction of the internal power and AUX buses from the left adjacent module to the
subsequent modules on the right.
BaseUnit, light-colored
Inserted as first BaseUnit and opens a new potential group with electrical isolation. The
power and AUX buses are separate from the adjacent module on the left. It feeds the supply
voltage.
Baud rate
Speed at which data is transferred, indicating the number of transmitted bits per second
(baud rate = bit rate).
BU cover
Cover for unused slots on the BaseUnit or placeholder for planned I/O modules. For a future
expansion, the reference identification label of the planned I/O module can be kept here.
Bus
Joint transmission path to which all participants of a fieldbus system are connected; has two
defined ends.
BusAdapter
Enables free selection of the connection technology for the PROFINET fieldbus.
Channel fault
Channel-specific fault, such as a wire break or short circuit.
In channel-specific passivation, the affected channel is either automatically reintegrated or
the fail-safe module must be removed and reinserted after the fault has been eliminated.
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Distributed I/O system
System Manual, 09/2019, A5E03576849-AJ