Rating 
Thanks 0
| 3/3/2008 2:08 PM | |
|
Posts: 15 Rating:
|
hi there! i got 6 slave stations, communicating with one master through radio modem, and the master must be enabled for data transmission to both a local network and a remote PC for control and monitoring. local network is profibus, and the remote one will be a leased line (2 MB/s). i want to know : 1- is it possible to use pcanywhere and connect the local server and remote station? 2- is it possible to connect the master PLC via a modem to the leased line and then to the remote pc? noting that the remote pc is using Wincc, i want to know if there is any devices, adapters, programs or licenses needed or not thank you |
| 3/3/2008 6:01 PM | |
|
Posts: 5822 Rating:
|
Hello, I would like to know what you want to use to communicate over the Lease line. If it is TCP/IP I think it should not be a big problem because the Protocol is not really time sensitive. That way you can collect some data too... but using PC Anywhere is really resource consuming, so it will take as much as it can on your leased line... This is not really easy. Will all stations that need to communicate to the WinCC Station be connected to the leased line via TCP/IP? If you want to use PROFIBUS I see the Problem that you will have a hard time to interconnect over PROFIBUS between the two PCs. You will have to do some tests to get to know if this runs... you will have a special configuration. Best regards J_Bell |
| 3/4/2008 5:27 AM | |
|
Posts: 15 Rating:
|
Hello J-Bell The first communication designed between 6 slaves and the master, was radio modem using RS232 port connected to RS232c module with Modbus dongle, and after realizing that we are not able to use Modbus on RS232c module for multipoint connection, we switched to RS485 module, so we got both possibilities for RS485 and RS232 because we have not purchased the radio modem yet, and also we have RS232 modules which are not changed with RS485 modules yet. So let's say in brief, we got modbus protocole, which is still being struggled!!! |
| 3/4/2008 9:41 AM | |
|
Posts: 5822 Rating:
|
Dear gama, I am sorry, but I fear that you will not be able to access the CPU via a Modbus Network, the CP used here, a CP 341 or 441-2, is not able to handle such functions at all. Best regards J_Bell |
| 3/4/2008 11:11 AM | |
|
Posts: 15 Rating:
|
Dear J_Bell I'm a little bit confused with your answer, you mean there is no chance to send data to the remote station or to communicate between the PLCs? complete situation: 6 PLCs with CP341 RS232 or RS485 using ModBus protocole, 1 master with the same CP-341 and protocole, with an ethernet card, communicating with all slaves via radio modem, and a network including server,engineering and client stations. 1- you mean no chance to use the mentioned configuration or to send data to remote station? 2- what should be done if the current modbus system not works? 3- what should be done to send data to remote station? please advice since this is a very important case as i am in trouble with programming for a design done by another person! |
| 3/4/2008 11:49 AM | |
|
Posts: 5822 Rating:
|
Dear gama, well... as the information I receive from you continuously changes I draw a scheme what I think you have till now. If you have changes please change it the way you have it. So, referring your questions I can tell you that depending how the configuration looks like, if the ?? is Ethernet and the local PC (Server??) is also connected to this Ethernet both PCs can access the Master PLC via Ethernet. Win CC can read and write values in the Master PLC... but this is the End. The PCs are not able to access the other Slave PLCs, because the Modbus interface does not allow this. The Slave PLCs can communicate with the Master and the Master may provide this Information to the PCs, but a direct communication between the PCs and the Slaves will not be possible. Even Communication between the Slaves will only work over theprogram on the Master... so think about it. As an alternative I would choose IWLAN, there you can access the complete Network and each node is able to communicate with another. Best regards J_Bell AttachmentConfiguration.zip (217 Downloads) |
| 3/5/2008 9:05 AM | |
|
Posts: 15 Rating:
|
Dear J_Bell Sorry for the mess up. I have changed the configuration according to the plan. I hop the modbu part works, though i am not quite sure. First Q : Does the network work with RS232 Modbus or must be changed to RS485 modbus modules? Second Q : I think there are two ways to communicate with a remote station, shown with 1 and 2 in red color, so the red dotted lines are the 2nd question, which one is practical and is there any other ways? What devices (HW or SW) are needed? I thank you so so much to keep in touch AttachmentMy Configuration.zip (189 Downloads) |
| 3/5/2008 11:39 AM | |
|
Posts: 5822 Rating:
|
Dear gama, let me try to answer your last question first. J_Bell |
| 3/5/2008 2:04 PM | |
|
Posts: 15 Rating:
|
Dear J_Bell I strongly appreciate your attention, and thanks for your valuable help. I decided to change from RS232 to RS485 because of the data in CA01 catalogue under CP341, which has mentioned "no data line for modbus protocole" , and many others mentioning that its not suitable for multipoint, and we recognized the network az multipoint. Yes! the master PLC is responsible for all data communication between PCs and PLCs. Can you please tell me where to look for a 'how-to' to communicate with TCP/IP? I want to know how can I represent the remote station to the system as a client. |
| 3/5/2008 2:14 PM | |
|
Posts: 5822 Rating:
|
Hello, WinCC and WinCC flexible contain drivers to use S7 Communication over TCP/IP, so if you refer to your S7-Channel or you use the Connection configuration and you direct the CPU as your endpoint it should work anyway. Best regards J_Bell |
Technical Forum - SiePortal Community
We are working on a new user interface with better overview and more relevance.
Follow us on