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Has anybody implemented MODBUS communication between Omni Flow Computer 6000 and Honeywell TDC-3000 through SI? If yes, then please suggest how to do it.

Well we are also facing the same problem.
The main problem is regarding the starting address of numerics.
All address 40001, 20001, 80001, 001,0201,0401, give either datatype, or msg time out error.

we have checked the communication using modbus tester, on both sides i.e, from DCS and to OMNI, they are both communicating with PC having software OMNI modbus tester.

But TDC3000 and OMNI6000 are not communicating.

Plz does anyone have the answer

The Omni Flow uses the Enron Modbus protocol. In the Enron Model you have 32 bit registers rather than 16 bit registers. This means for instance if you request data from register 400001 with a regular Holding register request for one register you will get 4 bytes (2 registers) in the response rather than 2 bytes (1 register). I do not believe the TDC-3000 can do Enron Modbus requests so you will need to bridge the data from the OMNI to a standard Modbus RTU model.

You can use the Kepware Modbus Suite, Modbus RTU driver supports the Omni Flow Serial and Ethernet models. It also supports Modbus Ethernet and Serial RTU Slave protocols. This makes the server look like an RTU device to Modbus Master Device. You then use Kepware's LinkMaster to bridge the data between the OMNI ahd the RTU Slave and the TDC-3000 can read the data using normal requests.

You can Talk to Kepware Sales or Technical Support for more information. This process is quite common for our customers.

Fred Loveless
Senior Application Engineer
Kepware Technologies
http://www.kepware.com

Sir,

I would request you to go through the following technical bulletin.
http://www.omniflow.com/support/technicalbulletins/980201 .pdf

It states that OMNI has readily tested with TDC 3000, using Modicon compatible protocol, Modbus RTU. But the problem is the starting address index, which we need to state in Serial Interface Point of TDC3000.

Kindly reply.

Hi there,

I work for a company called HMS and we manufacture, among other things, gateways. We have a gateway that can be configured to poll one register and handle the 32 bit response. On one side of the gateway, it will act as a standard Modbus RTU slave device and the other side can be programmed.

For more information, go to:
http://www.anybus.com/support/support.asp?PID=317&ProductTy pe=Anybus%20Communicator

or send me an email at:
support at hms. se

/Pat