Managing Multiple Compressors
Managing a compressed air system can be quite challenging, so you can imagine how it can be frustrating to control multiple compressors that are located in different rooms. If you are manually controlling your compressed air system and you set up a strategy that uses local compressor pressure settings, it is possible that you are consuming a whole lot more energy than you should. If you address this issue, you can substantially reduce your energy bill, as well as achieve a much more reliable air pressure.
How Compressors Control Pressure
Let’s focus on the control of rotary screw compressors as they are the most common kind used for industrial applications anyway.
Pressure, as you know, is a very important parameter in your compressed air system. If it does constantly meet the minimum required pressure, you can expect your machines to malfunction. It will definitely affect your production, too.
It would have been nice if you could just set your compressors at the minimum required pressure and never have to worry about it. It would then control itself, start, stop, load, and unload to make sure that it has the perfect pressure output and is at it its optimum energy consumption. However, that is all wishful thinking, and you know you’ll always worry about pressure differential.
Why Part Loading Is Very Inefficient
One incorrect strategy that you might be doing would be setting all the compressors to the same pressure setting so that they will share the load. Yes, al the compressors would keep the system pressure within the same pressure band and share the system load – at the cost of a very high energy penalty. Such a setting is only efficient at full load.
When you run a compressor at 30% load, it could consume around 60% to 80% of full load power. So if you run three compressors all at 30% load, it may consume twice what a single fully loaded compressor would consume. Imagine what it can do to your energy bill if you’re using this strategy for eight or nine compressors.
So in any system, the optimal strategy would be to maintain all compressors fully loaded, except for one. The trim compressor (the one that takes the partial load) is chosen by assessing which compressor works best with partial load.
Move the Sensing Point and the Automating Control
For you to achieve optimized control, the pressure the compressors are using should be consolidated to just one common value. The first step in accomplishing optimal control would be to make sure that the compressors in your system are somewhat seeing the same pressure. Additionally, if there are multiple compressors in different rooms, you’d want some kind of automation and sensing system that can help you control the pressure from a single pressure point in the system.
If you want to know how you can control your compressor, all you have to do is ask. C.E.D. Compressed Air Inc. can help your operators be more adept at running your facility’s compressed air system. Call us!