Beckhoff KL9020 Documentation page 27

Typical diagnostic LEDs of a Fieldbus Coupler
LED I/O RUN LED I/O ERR
(green) (red)
on off
off flashes
off off
Behavior in case of an error
If the communication between two or several bus terminal blocks of a K-bus extension system is interrupted
• the green RUN LEDs go out on the RJ45 sockets for the incoming K-bus extension (K-bus IN) on all
KL9050s,
• the red ERR LEDs light up on the RJ45 sockets for the incoming K-bus extension (K-bus IN) on all
KL9050s,
• the green LED I/O RUN of your Fieldbus Coupler will go out;
• the red LED I/O ERR of the higher-level Fieldbus Coupler will flash rapidly, indicating an interruption of
the communication.
Flashing Code
If you now perform a reset for the Fieldbus Coupler, the Fieldbus Coupler searches for the cause of the fault
and indicates it as a flashing code via the LED I/O ERR.
A flashing code is made up as follows:
• rapid flicker
• short break
• LED flashes m times for error code m
• short break
• LED flashes n times for error argument n
• short break
Count the error code and the error argument. The flashing code is repeated continuously.
The error code for a K-bus interruption is 4. The error argument indicates the Bus Terminal after which
communication was interrupted. Examples are shown in the Fault table for K-bus interruption [} 28].
KL9020, KL9050
Meaning
Data transmission on the K-
bus is active
Data transmission on the K-
bus is interrupted
Data transmission on the K-
bus is interrupted
Version: 2.1.0
Possible causes
• Supply voltage present
• Connection established properly
• Bus Terminal not plugged in properly
• Configuration error
• A mounted Bus Terminal is defective
• Supply voltage for the electronics in the Fieldbus Coupler
has failed
• Fieldbus Coupler defective
Diagnostics
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