Hi,

Need to setup a configuration with a S7-1200 CPU1214C and CM1241 RS422/RS485 which has to communicate (read and if possible write) with multiple Mastervolt chargers via a masterbus/modbus converter.

Has anyone experience with this? I don't know how to start and the Mastervolt documentation is very brief, and Siemens doesn't describe Modbus function code 23 which Mastervolt is using together with the Mastervolt addressing IDB/IDAL codes.

It would very helpfull if someone has an example program for this?

Your help would be much appreciated!

Thank you for your reply Kaulquappe !

Is there any way to have a workaround for that function code then?

From what I understood from FC23 is that it is performing 1write/1read operation in a single modbus transaction. I don't know if splitting those operations will work eg.: first a write operation followed by a read operation instead  (2 transactions) or only reading

And if it don't work that way, what are the options left? We are only using S7-1200 PLc's and usage of a different kind of PLC just for reading the chargers seems bit strange to me?

Is there any magic available?

Dear MarkBo,

Did you find a solution to your problem in comunicating with modbus to the mastervolt batterycharger? I just bump into the same situation.

yours,

Jan