By Ron Marshall for the Compressed Air Challenge
An electronics component manufacturer was having trouble with their compressors. Despite having purchased a very expensive and sophisticated control system, they were experiencing problems with their automatic compressor control.
The system is designed to control the four large air compressors in their compressor room by coordinating the pressure set points. If the plant demand increased to where an additional compressor was required, then the controller would automatically start one. If the load dropped off, then the controller shut down a compressor. All of this was done while keeping the plant pressure and a nice, efficient low level.
But problems were occurring after power outages. If a power outage tripped off the compressors, the control system would try to start all the compressors in a very short period of time, tripping the main breaker to the compressor room. A main breaker trip is a major event—and the subsequent investigations would cause many hours of production outage, getting the maintenance supervisor in very hot water.
As a result, all the compressors but one spare unit were run in manual control. This control method caused the compressors to run individually with very poor efficiency and inadequate pressure control, but the maintenance supervisor was happy, the plant kept running fine, and there were no breaker trips. Things were left to run this way for many years.
An expert was called in to assess the compressed air system. In a few minutes, the control problem was discovered as an incorrect control settings, the control did not wait long enough before trying to start the next compressor. The correction was a simple click of a mouse settings change. The technician who initially set up the control system had not been properly trained, and so did not correctly commission the unit. The maintenance supervisor never questioned the settings. As a result, many thousands of dollars of power was wasted.
Learn more about compressor control in our next Compressed Air Challenge seminar in your area. Visit www.compressedairchallenge.org for more information.
Filed Under: Pneumatic Tips