Newbie in SCADA world, need some directions


Thread Starter



i'm a technician from an engineering service provider and our services includes Power System Automation.

Just a brief background, I have 9 months experience in industrial (factory) automation, in my previous company, I've already handled programming and troubleshooting machines using PLCs specially from Mitsubishi, Omron, and keyence, however I haven't got a chance to practice designing HMI panels as I left that job. I also have some sort of background in programming (ASP, JavaScript, Python).

I've been here in my current company for almost 2 years now, our main service is testing substation equipments and most of the time I'm responsible for testing the protective relays and other IEDs and that is why I became interested in SCADA. I only have one colleague who is responsible for designing and implementing our SCADA projects, and having some background in automation, I am the one he always pick to go with him. Now that he resigned and about to leave the company, he is now in the process of turning over all his responsibilities to me.

Now my current experience in SCADA:
My first project is an Annunciation and Alarm Monitoring Panel with SOE capability. We used the SEL 2240 Axion (It's a modular RTU with a bunch of I/Os) and the HMI Software that we've used is the one that is built in to the RTU. I guess it's a good introduction or start for me as doing that project is very straight forward, all I need to do is wire the I/Os, assign the tags in the RTU, import the tags in the HMI, design the HMI and done. Now because of that project, our boss thinks that I'm really capable of doing SCADA projects that's why they allowed our engineer to leave.

We have a bunch of Automation projects in line and I'm worried that with my limited knowledge and without the help of my colleague, I'll be having a hard time. Our parent company carries the SEL brand thats why most of our projects use this brand, the only third party that we are using is the Cimplicity HMI software if the customer requires a 3rd party software.

Though with using SEL, we can build a basic SCADA system with it's own protocol and built in HMI. But if I need to build a more advance system using different IEDs, protocols and/or different HMI softwares, I guess there are lots of things to learn. We have a laboratory at our office complete with an RTU, I/Os, and a bunch of protective relays and meters) and with that I can simulate a small electrical substation but I dont know where to start.

First i'm not familiar with the different types of connections that they are using and when they use it like Serial (RS-232 and 485) and ethernet connections. Most of the time I use serial connection just to access the relays for programming and testing purposes, I don't have any idea why they choose that baud rate, parity, stop bits, etc.

Next is the different protocols. They said using SEL protocol will make everything auto configure (just like the EtherCAT when using the SEL 2440). But my next project requires me to use Modbus as per customer's requirement but my colleague said they also require time stamping in their system so we need to use DNP3 but because everything is SEL, we can use it's own protocol if the customer will allow it.

Next is the OPC server. He said that if I will use Cimplicity as an HMI Software, The OPC should read the tags first from the RTU first before the HMI can read the tags from the OPC server.

Last, do I need to study certain programming language to be used in Cimplicity? On my first project, we need to do some programming for some tags (but it's just a scripting language), if it's just the same with Cimplicity, I guess I won't need to bother that much with programming.

So all in all, this are the things that I'm trying to learn:

-Type of network connections

-Different types of protocols. Im also hearing alot about IEC 61850 recently.

-OPC Servers. My colleague gave me a copy of Cimplicity v. 8.2 Trial and it comes with an OPC Server. I also read about alternatives and saw Ignition from Inductive automation, they also have what they call OPC-UA. I also saw that OPC-UA at matrikonOPC while browsing. What does OPC really do with the tags after mapping it to the RTU using those protocols?

-Programming language. He said that Cimplicity use VBA or VB6 (I forgot) and I saw that Ignition use Java. How important using programming language in designing SCADA systems?

In my free time, I'll be playing in the laboratory but for now I'll be using SEL's own protocol and HMI but I want to experiment further and learn more. Are there any important things I need to learn that I missed? Thanks for patiently reading my post...

David Hackenbracht


Where I can't answer most of your questions I might be able to provide some information about RS-232.

The baud rate is basically the speed transport of bits per second. Faster, is generally better. The hardware mostly determines this.

Baud rate, stop bits, and the like are basically what have to be agreed upon by both sides. (sending, and receiving) It's the RS-232 protocol.

The most important thing is sending and receiving be the same. Hope that helps some.