Fault table for K-Bus interruption

Examples of fault indications in the event of communication interruption on the K-bus

Error

Display

Specific
display

Possible
cause

Remedy

no data transmission on the K-bus and K-bus extension

LED ERR of the Coupler Terminals KL9050 are on

LED I/O ERR of the higher-level Fieldbus Coupler flashes rapidly

K-bus or K-bus extension was interrupted

After any interruption of the data transmission on the K-bus, the higher-level Fieldbus Coupler requires a reset in order to restart the data transmission or to locate the fault.

LED ERR of the Coupler Terminals KL9050 are on

 

I/O ERR LED of the higher-level Fieldbus Coupler flashes after switching on in succession (flashing code):

  • fast
  • 4 times slowly
  • n times slow

 

The Ethernet cable of a K-bus extension is not plugged in correctly

Fault after the n-th Bus Terminal: ensure that the RJ45 plug is connected correctly.

 

The Function Switch of the last Coupler Terminal is not in position Last

Set the Function Switch to Last!

 

Wrong Ethernet cable

Fault after the n-th Bus Terminal: Do not use a crossed Ethernet cable for K-Bus extension!

LED Power Vk of the affected Coupler Terminal is not on

Supply voltage of a coupler terminal has failed

Check the supply voltages of the bus terminal block after the n-th Bus Terminal

LED ERR of the Coupler Terminals KL9050 are on

LED I/O ERR of the higher-level Fieldbus Coupler flashes rapidly

Ethernet cable too long

The length of the Ethernet cable between two terminal blocks must not exceed 5 m.

The overall length of the K-bus extension must not exceed 155 m (31 x 5 m).

Ethernet cable defective

Check the Ethernet cable.

 

Wrong End Terminal installed: The End Terminal with RJ45 socket (KL9020) is only used at the bus terminal block with the Fieldbus Coupler.

All extension terminal blocks must be terminated with the standard end terminal (KL9010)! See Notes on the topology of the K-bus extension.

Please see the documentation of your Fieldbus Coupler for further error codes (m¹4) and the associated error arguments.