Modbus and Citect

Y

Thread Starter

yan_comm

I am planning to put up a monitoring system using CitectSCADA software and the existing ION 7300 meters in our location.

I know that I can connect the meters in daisy chain using RS485. The meters are configured to communicate using MODBUS RTU protocol.

The computer to be installed with CitectSCADA is 1 km away from the meters and it can be connected to the meters using the local area network.

What are the things do I need to make this setup work?
Can I use a modbus gateway to convert MODBUS RTU to TCP?
Do I need OPC to get the data correctly?

Help please...
 
D

Darrin Hansen

From your description, it appears that our ETH-200 gateway should work for your application. One (or both) of the ETH-200�s RS485 ports could be configured to act as Modbus RTU masters, and they would then retrieve data from the meters and store it on-board. Once the data is in the ETH-200, it is then accessible via any other protocol/port. From an Ethernet perspective, you would be able to access the data via either web browser, Ethernet/IP or Modbus/TCP.

Looking at Citect�s web site, it appears that one of the drivers they make is for Modbus/TCP (they call it MODNET). If that driver does indeed allow the SCADA software to act as a Modbus/TCP master, then it can be used to retrieve the data from the ETH-200(s) via the Modbus/TCP protocol.

If interested, please refer to http://www.iccdesigns.com.

Best regards,
Darrin Hansen
ICC, Inc.
 
F

Fred Loveless

Hi,

As long as you have a Modbus Etherent capable communications package you can do this. There are several manufacturers that make Modbus Serial to Modbus Ethernet converters.

You could also use and OPC/DDE server like Kepware's KEPServerEX which supports Ethernet Encapsulation on its serial drivers. With Encapsulation a basic Ethernet Header and Footer are wrapped around the serial packet. There would be a serial to etherent converter attached to the serial device.

For more information go to http://www.kepware.com or contact Kepware Technical Support.

Fred Loveless
Support Manager
Kepware Technologies
 
The same application is carried by us using Secure Energy meter around 48 devices communication on RS485 and by using Sixnet RM-485-232-4U converter which converts to 485/232 and by connecting this with ET-GT-ST-3, which provides dual ethernet ports and communicates on MODNET u can acess data easily at OPC server.

For further deatails do contact me.

U.Ramesh,
rameshu @ masibus. com
 
You can use a sixnet mini ipm model 131 which has 485 ports and a single ethernet port and you can then use the SXDirect driver in citect to poll the data. You will have to setup the RS485 port on the mini ipm for modbus which is EASY to do...sixnet has in my opinion the easiest modbus setup of any plc on the market...

JJ
 
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