Welcome back to another issue of AutomationMedia's Ramblings.

There was time when HMI or industrial software communication with controllers was complex due to variety of reasons. Every one had his own versions of drivers and different type of interfaces. Big names of automation and control industry had some sort of monopoly. Not any more now…...

Thanks to OPC Foundation and OPC Data Access Specification to move real-time data from PLCs, DCSs, and other control devices to HMIs and other display clients. Previously OPC Specification is now called the OPC Data Access Specification.


Just 4-5 years back, if you were using HMI iFix software of Intellution (now GE), and wanted to use their ABR driver to communicate with AB controller like SLC, PLC5 etc, it was MUST to use RSLinks software layer. Customer had no choice, except to pay more and buy RSLinks. It was due to Rockwell Automation. End users had no choice as they have to buy this type of interface software to maintain previous investment. Now, it is not easy for manufactures to force customers to buy additional software.
In past following was only way to go if you want to access real time data in iFix from AB controllers:
HMI iFX > Intellution’s/GE’s ABR Driver > Rockwell’s RSLinks Software> PLC/Controller.

Now it is very straight forward and no need to buy RS Links Software..
HMI iFX > GE’s Industrial Gate Server (IGS) > PLC/Controller.

As customers know that OPC standard exist in today’s world, so they show concerns if manufactures do not offer OPC connectivity. Now customer’s expectation force manufactures of automation products (PLCs, DCSs, and other control devices) to offer support for OPC drivers.

Due to current and emerging OPC specification, automation and control’s engineers life is better now, less communication problems. If noting works, this path always work….

[Software + OPC Client] <> [OPC Server + Controller/Device].



Those who will adopt OPC standards on plant floor today, tomorrow thay can add better values as they will have choice of best buy in control market, best decision option and flexibility to add products from different manufactures in control systems, if they are not happy with existing one. Access to data from existing devices will not be issue.

Until next time,


Naeem Ismat
Naeem@AutomationMedia.com
AutomationMedia.com