I have a customer that wants us to use a S7-400 PLC. I don't get into Siemens too often (unless I have to). This machine doesn't do much and needs minimum I/O (turning on/off a motor, passing 1-2 analog signals)
The only S7-400 PLC with profibus is $15k! The lowest level module is only about $2k, but has DP/MPI.
From what I can tell, MPI is a subset of profibus that is more limited, but the connector is identical. Can the lower-level MPI/DP connect to a Profibus network without issues or will I need the (much) more expensive CPU?
Thanks in advance!
EDIT: After some more research, I think my confusion lies in the fact that the Siemens part number listed MPI/DP, but DP is just short-hand for Profibus-DP. For some reason in the TIA selection tool, it only says "Profibus" for the 416 CPU and DP for the other modules which made me think it was a separate network protocol. When I look at the datasheets for the 416 and 412, both mention MPI / Profibus-DP. If I am wrong, please correct me!
The only S7-400 PLC with profibus is $15k! The lowest level module is only about $2k, but has DP/MPI.
From what I can tell, MPI is a subset of profibus that is more limited, but the connector is identical. Can the lower-level MPI/DP connect to a Profibus network without issues or will I need the (much) more expensive CPU?
Thanks in advance!
EDIT: After some more research, I think my confusion lies in the fact that the Siemens part number listed MPI/DP, but DP is just short-hand for Profibus-DP. For some reason in the TIA selection tool, it only says "Profibus" for the 416 CPU and DP for the other modules which made me think it was a separate network protocol. When I look at the datasheets for the 416 and 412, both mention MPI / Profibus-DP. If I am wrong, please correct me!
Last edited: