ABBAC 800M PROFIBUS DP Configuration

Line Redundancy

The CI854/CI854A supports line redundancy for PROFIBUS DP. Therefore the two 

interfaces "PROFIBUS A" and "PROFIBUS B" are available on the baseplates 

TP854 of the modules. There is a Redundancy Link Module functionality 

implemented on the CI854/CI854A that handles the sending and receiving of data 

on the PROFIBUS. Independent of any configuration the RLM sends data on both 

lines and receives data only via one line. Regarding the receiving of data the RLM 

checks if the slave sent data on both lines and if the data is valid. The first received 

valid data on line A or B will be picked up and operated. It is possible that the slave 

sends data on both lines in parallel or only on one line. 

The monitoring of the line redundancy can be enabled or disabled. The default is 

disabled. The enabling is done via the parameter "Line redundancy" in the settings 

If the non-redundant slave gets disturbed the CI854/CI854A waits for watchdog 

time before connection down will be indicated for the slave

for CI854/CI854A. If the line redundancy is enabled the warning "No activity on 

PROFIBUS" will be indicated for the specific line in the case of a failure, for 

example if there is a fault on the PROFIBUS cable. 

Please enable the monitoring of line redundancy, if

– redundant slaves according to the PNO redundancy specification are used 

and/or 

– non-redundant slaves provide a line redundant interface and/or 

– non-redundant slaves with only one PROFIBUS interface are connected to 

the CI854/CI854A with a RLM01.

Status Handling

Status Handling for DP-V1 Master Unit

Every status information for CI854/CI854A in terms of hardware and software 

errors is indicated via the unit status. The unit status is used to present the status of 

the HW unit in Control Builder M while CBM is in online mode. In addition 

alarms/events are generated based on the unit status (please refer also to Alarms and 

Events on page 36). For special reasons also the access to the unit status via the 

controller application is supported.