I'm a newbie in PLC.
Currently I have an s7-200 cpu + cp243-1 and an s7-1200 cpu connected to a factory network (ethernet). The goal is to transfer data to an Oracle database from these two cpus. My part of work is to convey data to the opc server. I'm considering 3 variants:
-Pc Access OPC (6ES7840-2CC01-0YX0). Really cheap, but I've noticed that there is "SINGLE LICENSE F.1 INSTALLATION". I wonder what it means? Does it mean that I'll be able to install it on one machine for multiple times or just one time? Also, as far as I can see on the web, there could be some issues when working with S7-1200 because it was originally designed to work with s7-200.
-Simatic Net OPC. What are the advantages of this one?
-Matrikon Siemens S7 PLC OPC Server. Seems a good one, but expensive.
I need to transfer only about 30 tags and that keeps me from spending money on Matrikon and in this case my priority is Pc access, but some say that it can be unstable sometimes. Btw I have a WinCC 6 (not flexible) installed on some computers in a factory network. As far as I know WinCC 6 includes its own opc server (not sure). So is it possible to transfer tags there? So far I've found 2 sources:
Here they say that OPC is needed to communicate with WinCC.
Here they imply that additional opc is not needed. Comes as a part of WinCC..
Honestly, I'm not experienced with WinCC, so I need your advice.
Matrikon is specialised in OPC Solutions. Their OPC servers are great and they offer a great support in OPC solutions. Matrikok also has a great free OPC simulator, viewer and paid utilities and tools.
Simatic NET OPC comes 'complimentary' with an S7 protocol license. Which is also not very cheap. This will not work with an S7-200. OPC server with Siemens is managed with PC Station Configurator. This is a program that also comes with the S7 Protocol. This Station Configurator needs to be configured with Step 7 V13 prof. in demo mode. There you configure which tags from the PLS may be read/written via OPC. This sounds cumbersome, but this way of configuring is done for everything on a PC. From a small solution like OPC to their big DCS systems.
Siemens is specialised in their PLC's and SCADA not OPC. Beyond the OPC, their support stops. While Matrikon start to support.
PC Access is for the S7-200 only. You can use it only on one pc. So no floating licens or central license server possible. Personally I would ditch the S7-200 for a new project. This range of PLCs is no longer supported and I doubt that there will be a MicroWin for Windows 8.
Note that the S7-1200 needs extra settings for OPC due direct and inderect addressing. See: http://support.automation.siemens.com/WW/view/en/39960679
WinCC is their SCADA solution and has also OPC functionality. Forget this whole option with WinCC.
I would recommend to contact Matrikon or Siemens via their support or sales. Even small customers will get an answer within a working day. Perhaps there is a tool available at Matrikon to connect Oracle directly to OPC.