Railline, several Modbus addresses for the same variable? PMA Railline interface manual

-         PMA Railline interface manual:

-         Variables can be accessed in several ways over the different interfaces.        

-         These interface descriptions list a selection of possible data of 1 device.

-         According to the hard- and software options there are different variables available.

-         Additionally, the data bases they are made of contain “all possible” data of at least the controller family, e.g. Rail line.

-         The single device does not need them all. This explains the gaps in the Modbus addresses.          

-         You can access variables by their direct Modbus address e.g. via Modbus RTU.          

-         Some data are copied to a special area to have them more compact:

-         Signals needed by BlueControl are automatically copied to an area called “Visual”.

-         This is what customers asked for to see in BlueControl’s Online mode, or what you can save as a BlueControl trend.

-         This data has been made available for customers.          

-         And a customer can create his own list of data:

-         Add variables of a RL module into bus cache via “bus data read” and “… write”, e.g for the KS45 in Rail line.

-         Then the bus coupler collects and updates the data from all the modules in the RL system in the background.

-         If a message asks a value, the bus coupler can answer from his cache.

-         After creating this list while commissioning, this communication is just what you need, quick and compact.

-         Another advantage: You can ask several values from the cache in 1 message.                    

-         Therefore there are different Modbus addresses for the same variable.          

-         Of course, under certain conditions some variables look the same, as long as the conditions match:

-         Like SP(intern) and SP(eff.ective) show the same value, if the setpoint is switched to SP, not to SP2,

-         no ramp working, no profile running etc.