Diagnosis

Ethernet state (FieldbusState)

In many cases it is important to know whether the communication with the higher-level master is still OK. To this end, link the FieldbusState variable with your PLC program.

FieldbusState

EthernetType

Here it is possible to determine which Ethernet protocol is accessing the PLC variables, and thereby triggering the watchdog (for example, the data in the Default Config area starting from addresses %IB1000 and %QB1000).

Reading fieldbus state by ADS

In default or TwinCAT configuration the fieldbus status can be read via ADSREAD.

First word (FieldbusState)

Second word (EthernetType)

State of the K-Bus

An internal bus or Bus Terminal error is indicated in the K-Bus state. A more precise fault description can be obtained via a function block (in preparation). To this end, link the K-Bus state variable with your PLC program.

Reading K-Bus state by ADS

In the default configuration or in the TwinCAT configuration the K-bus status can be read via ADSREAD.