BECKHOFF BC2000 - Manual (Page 10)

Basic Principles
9 BC2000
Structure of the potential
levels in the bus terminal
system
24VDC
Peripheral level
Bus coupler Bus terminals
Terminal bus (K bus)
Field bus
Operating Modes of the Bus Terminal
Controller
Immediately after being switched on, the bus terminal controller checks, in
the course of a “self test”, all the functions of its components and the
communication of the terminal bus. The red I/O LED blinks while this is
happening. After completion of the self-test, the bus terminal controller
starts to test the attached bus terminals (in a „bus terminal test“), and reads
in the configuration. The bus terminal configuration is used to generate an
internal structure list, which is not accessible from outside. In case of an
error, the bus terminal controller enters the „STOP“ state. Once the start-up
has completed without error, the bus terminal controller enters the "fieldbus
start" state.
Start-up behaviour of the
bus terminal controller
Power On self test
Bus terminal test
Structure list
PLC Start /
Communication start
Stop
OK Error