Moeller LE 4-505-BS1, Hardware And Engineering

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Normal operation
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02/98 AWB 27-1314-GB
configuration mode, all slaves are activated
independently of the permanent configuration.
In the next step, data is exchanged with the activated
slaves. If the PLC is in HALT mode, the outputs of the
slaves are set to 0. If the PLC is in RUN mode, the
inputs and outputs of the slaves are transferred to/
from the ASi master. The following LEDs are lit on the
ASi master in this status:
ASi-Power OK
ASi active
“Configuration OK” lights if actual
configuration = permanent configuration
If the power supply voltage of the ASi bus is below
the specified range (26.5 – 31.6 V DC), the
“ASi Power OK” LED goes out and all slaves are
decoupled.
Data exchange with the slaves then no longer takes
place.
If the “Configuration mode” LED lights with the PLC
in RUN Mode, the ASi master is not operating in
protected mode. This situation can arise e.g. when
the ASi master is in configuration mode and the PLC
is switched from HALT to RUN mode and a slave is
detected on the bus with address 0.
Normal operation In Normal Operation, the ASi master polls all
activated slaves sequentially in order of increasing
slave address.
Three retries are made if an error is detected with one
of the slaves. If the third retry is also unsuccessful,
the process input image for this slave is set to 0.
At the end of each ASi cycle, the master checks
addressed from 0 to 31 for newly added slaves. New
slaves which are detected are added to the actual
H1314G.BK Seite 53 Freitag, 2. Juli 1999 9:02 09