RTU211 Modbus Interface
Good Day,
Does anybody has experience in Modbus Interface between AC410 (Master) with CI534V02 and RTU 211 (Slaver)?
We
Thanks for your help and sharing.
Thanks,
WenBin
This message was imported from another forum and originally authored by WenBin Xu/OU=SGIND/O=ABB
Does anybody has experience in Modbus Interface between AC410 (Master) with CI534V02 and RTU 211 (Slaver)?
We
Thanks for your help and sharing.
Thanks,
WenBin
This message was imported from another forum and originally authored by WenBin Xu/OU=SGIND/O=ABB
Asked 18 years ago
Answers
0
Wen Bin,
Modbus Addresses all start with 1,2,3 or 4. In reality, this number really only describes what type of data is held in the word ( boolean or integer ) and most PLC's won't care about the first digit. Hence 1001, 2001, 3001 and 4001 are all the same memory location in the PLC.
Don't get confused by the word "offset". If you want to read RTU address 40096, then thats the address you put in the Read command. The only exception to this is if you are reading/writing more than one memory location at the same time. In that case, put the start location and the number of words to read/write. Every memory location in this range must exist in the PLC or you will get an "illegal address" error.
Hope this helps a little.
Regards
Rob L.
This message was imported from another forum and originally authored by Robert Lyon/OU=NZABB/O=ABB
Modbus Addresses all start with 1,2,3 or 4. In reality, this number really only describes what type of data is held in the word ( boolean or integer ) and most PLC's won't care about the first digit. Hence 1001, 2001, 3001 and 4001 are all the same memory location in the PLC.
Don't get confused by the word "offset". If you want to read RTU address 40096, then thats the address you put in the Read command. The only exception to this is if you are reading/writing more than one memory location at the same time. In that case, put the start location and the number of words to read/write. Every memory location in this range must exist in the PLC or you will get an "illegal address" error.
Hope this helps a little.
Regards
Rob L.
This message was imported from another forum and originally authored by Robert Lyon/OU=NZABB/O=ABB
Answered 18 years ago
0
Hi,
If you follow the RTU User Manual, Part 4 page31. You should set all the address offsets
to 0.
Regards,
Linh
This message was imported from another forum and originally authored by DoTuan Linh/OU=SGIND/O=ABB
If you follow the RTU User Manual, Part 4 page31. You should set all the address offsets
to 0.
Regards,
Linh
This message was imported from another forum and originally authored by DoTuan Linh/OU=SGIND/O=ABB
Answered 18 years ago
Add new comment