Industrial OPC is a vital, yet relatively small component in a SCADA system. This is because OPC is typically responsible for the software communication aspect between a piece of industrial software, and a monitoring or control device (sensors, PLCs..etc). It may not be as complex as analysis algorithms embedded in data historians , or as fancy as visuals reflected on HMI screens. However, Inspite of this, industrial OPC can never be ignored. OPC is the equivalent of those resilient nails that make a fancy piece of furniture come together.
Today, I found myself wanting to talk about a SCADA related topic a little bit. What is SCADA you say? Well, you can either check this article, or just read on. SCADA is a world that I live in, where software meets temperature sensors and pressure gauges. SCADA is the software layer that sits between a human being and a bunch of devices that control and monitor operations in a factory, oil pipelines in the desert , or power generation substations… you get the idea!! Process historians are not considered SCADA systems by themselves, however they are vital companions in almost all SCADA related project. You can put both Process historians and SCADA systems under the umbrella of industrial software.
This article serves as a practical guide into how to build a Modbus driver. I use the Go (Golang) programming language because I like it . However, the principles outlined should apply to any stack.
I happen to be a software engineer who works in SCADA. What does that mean? it means that a lot of my days involve making various pieces of complex software work in harmony with industrial devices like one big happy family. In order to make software talk to industrial devices, we use protocols that both the devices and the software can understand. Some protocols are fairly complex and some are fairly easy, some are frustrating and some are fun. Amongst them Modbus is the most popular.
This article serves to provide a decent overview of the industrial software industry. This industry is the gate to the intelligent solutions that drive the success of industrial operations in factories, plants, pipelines, electrical grids, and similar facilities. Let’s start the journey by covering SCADA which is the main component of any industrial software.
What is scada?
A SCADA (Supervisory Control And Data Acquisition) system simply refers to the layers of software and infrastructure that sit between a digital screen, and any control or measuring device. SCADA is used to issue control commands to remote devices like valves or pumps, read values from those devices, and analyze device data when needed. SCADA systems can be small in order to manage field devices that are in close proximity inside a single facility , or expand to handle devices that are spread across vast geographical areas (like sensors on oil pipes). SCADA exists almost everywhere in this day and age.