Get Block

I have a "Data collection" PLC (CPU314) with an ethernet module (CP343-1 lean). My requirement is to read data from 3 other PLC's on the network, a) "Rotopacker PLC" (CPU315-2 DP). b) "Palletizer PLC" (CPU315-2 DP). c) "Bag applicator PLC" (CPU315-2 DP). all with ethernet modules (CP343-1 lean).

I need to read a datablock from each one. The information will be correlated into a data block within the "data collection PLC" ready for SCADA to read and generate a production report.

I am following the support example of the Get Block in which S7 communication are used, however I get an error in Netpro when i select S7 comms, if I select tcp/ip all is ok. With tcp/ip selected no connection is shown in the GET Block connections, if I select a new connection I end up with an error.

The 3 PLC's I am reading from are under warrenty from another company, so I am not allowed to modify them, but I am allowed to download to the hardware configeration (managed to get permission for this due to IP address changes).

Each remote PLC only has about 40 bytes of data in the datablocks I am interested in.
I am currently programming the "Data collection" PLC offline and away from the site.

My first question is am I using the correct block (Get Block) to begin with?
if so do I need to bother with S7 communications or just use tcp/ip.

Thanks for the reply.
So if I obtain a CP343-1EX21 module for the "Data collection" PLC I will be able to achieve my goal?

Is there any other method with the hardware I have already,

regargds Trerank