By Eamonn Ryan derived from a SAIRAC Johannesburg Centre TechTalk on 12 February
In the February SAIRAC Johannesburg Centre TechTalk presented by Robert Fox, SAIRAC national president with over 31 years of experience, he discusses the critical differences between open-source and proprietary solutions for HVAC systems. As a senior cost and design estimator at Club Refrigeration, Fox has extensive insight into both the challenges and benefits associated with each system. This is Part 7 of a ten-part series.
Node-RED is actually pretty easy to learn, and I find it even a little easier than Python. Arthur Hidden/© RACA Journal
Q: Have you used Raspberry Pi or Arduino for power management and control?
I’m not a huge expert in Raspberry Pi, but I do know it’s a great platform for learning. For instance, you can use it with Python to control various systems. I’ve worked with it for a few projects, but I mainly focus on what I need to know for HVAC and controls. If you want to get into programming, you don’t have to go straight into buying expensive PLCs. You can start with platforms like Arduino, which is much more affordable. It’s open-source, and you can connect sensors to it and learn programming. It’s a great way to get your feet wet without spending too much.
Q: You mentioned building your own time attendance system—how was that experience?
I got frustrated with the proprietary time attendance systems that were available, so I decided to build my own. It’s been running for almost a year now, and it hasn’t had a single glitch. It’s definitely a learning experience, and I’d say the best part is when you see something work after all your effort. That’s the sense of achievement you get from programming. So, I encourage everyone to experiment and have fun with coding—it’s a great way to push your boundaries and learn new things.
Q: Any advice for people just starting with programming or looking to push their limits?
Always keep learning. Don’t get stuck in a rut, and try to learn something new regularly. For me, programming has been such a rewarding experience because it challenges you and gives you that sense of accomplishment when things work as expected. Even when I was just starting out, I’d encounter roadblocks, but I stuck with it because it’s all part of the process. If you enjoy problem-solving and building things, programming can be incredibly fulfilling. And, most importantly, don’t let anything hold you back from exploring new areas of learning. The more you push yourself, the more you’ll grow.
Q: Can you share more about Node-RED? What does it do?
Node-RED is actually pretty easy to learn, and I find it even a little easier than Python. It allows you to pull in pre-built nodes and link them together to create your projects. It’s a graphical tool, so instead of writing lines of code manually, you use these nodes to set things up. The really cool thing is that while you’re writing your code, some of these nodes also come with interfaces, so you can do both your coding and your web interface all at once. If you want to get more advanced, you can also write custom code inside function blocks, which gives you a lot of flexibility. I use Node-RED for various projects around my house, and it’s been really helpful. It’s much more affordable than PLCs, which are expensive, and you can build things more easily with a Raspberry Pi, which only costs around two to three thousand rand. It’s a great alternative for home projects or smaller-scale applications.
