I have connected a delta v serial card to an Omni 6000 flow computer. I am communicating using an Enron Modbus driver to access all of the Modbus Registers the Omni uses. In the 7000 register range I have numbers updating but they do not correspond with value in the Omni. I.E. register 7809 in omni is 500 and I receive nothing resembling this number. I have tried different data types etc, but nothing seems to work. As well in the Enron modbus driver from Mynah I was unable to use the "device data type" =1 as it gives me comm's errors. I can only use device data type = 2 which is for 3000 series registers. If anyone has used this interface please reply with some assistance.

Thanks.

 

Enron Modbus is an old variant of Modbus originally developed for Daniel flow computers in the US gas transmission market in the late 1980s. It is much more limited in scope than and is different to the OMNI Modbus implementation.

I understand that The OMNI implementation has a world-wide installed base with many energy companies worldwide in their control systems where they use Honeywell, Rockwell, Yokogawa and others. Drivers exist from Wonderware, KEP, Intellution, Honeywell, Rockwell/Prosoft so can't imagine where you are going wrong?

OMNI has Technical Bulletins dealing with Modbus on its Website, http://www.omniflow.com on this subject e.g. Honeywell etc. Site also has Manual downloads, particularly Volume 4 dealing with its Modbus Data base.

 

Just an after-thought. Look for OPC server solutions at http://www.automatedsolutions.com. This is also an excellent method to access leading hydrocarbon oil & gas custody transfer flow computers such as OMNI from controllers such as Delta V and Honeywell.

RS232/485 and Modbus/TCP over Ethernet have been proven with Automated Solutions OPC and OMNI comms.modules and Honeywell controllers.

Hope this helps.