cip connections

[agarb]

I am looking at a potential application for some RMC75 controllers. I am using an Allen-Bradley 1769-L32E PLC and communicating via ethernet i/p. My PLC can accomodate a max of 32 cip connections, so I am trying to add up the maximum potential cip connections for my entire system to make sure I am under the limit.

How many cip connections would it take for my L32E to interface with qty. 2 RMC75?

[agarb]

Info from a private email that Bruce Coons the regional Delta sales manager sent me:

The RMC doesn’t really require any CIP connections. Yet, the RMC75E and RMC150E support the following number of CIP connections:

· 32 CIP connections (using MSG blocks results in this type of connection)
· 4 CIP I/O connections , of which only one can be a controlling connection. The rest of the I/O connections must be “listen only”, but these are rarely used.

So, an RMC requires none, but will use one per RMC for control connection to your PLC. Thus maybe the answer, whether you have a one or two axis RMC75 or a 2, 4, 6, or 8 axis RMC150, you will use just one control connection per RMC. I’m thinking the other case which does not apply to an RMC, may be that each axis requires one CIP connection.

On one four axis machine, with two RMC75 two axis controllers, you would use two CIP connections per machine. With all four axis in one RMC150, then just one CIP connection. The double two axis RMC75 solution will provide you the benefits of running less wires as you note. Either scenario will leave you with multiple unused CIP PLC connections.

That is the info I was looking for.

[Peter_Nachtwey]

More info can be found in the on-line help.
Go to the index and search for Ethernet/IP. At the bottom of the page there is a section on the number of connections available
There is more if you search for multiple connections. It is possible to have a couple of HMIs consuming data too.
If I read the request your are concerned that each axis requires a connection but the PLC only needs one per RMC. One customer had one Control Logix controlling 30 RMC75Es ( 60 axes ) no problem.
machinedesign.com/article/earthq … onics-0217

[agarb]

@Peter Nachtwey

More info can be found in the on-line help.
Go to the index and search for Ethernet/IP. At the bottom of the page there is a section on the number of connections available
There is more if you search for multiple connections. It is possible to have a couple of HMIs consuming data too.
If I read the request your are concerned that each axis requires a connection but the PLC only needs one per RMC. One customer had one Control Logix controlling 30 RMC75Es ( 60 axes ) no problem.
machinedesign.com/article/earthq … onics-0217

My concern was that each RMC may require more than one connection. For instance, a remote rack of A/B point I/O requires 1 cip connection for all the digital I/O modules combined plus 1 connection for each analog or speciality module. I have 3 racks in my system that each use between 4 and 6 connections. Likewise, a PanelView+ takes 5 cip connections to communicate with my PLC. If each RMC took 5 connections like my PanelView+, I’d exceed my PLC’s connection limit and have major issues!

The project you referenced where one cutomer had a single ControlLogix controlling 30 RMC75s sounds pretty neat! However, it is different because you can add multiple ethernet modules to the ControlLogix rack. Each module will accomodate either 64 or 128 connections depending on the exact part number of the module. In my case, I am using the low-end CompactLogix L32E which only has a single built-in ethernet port that has a max of 32 cip connections. I can not add additonal ethernet modules to the L32E.

Hope this makes sense.