UPS application: Aviation manufacturer cuts downtime, uses industrial uninterruptible power supply
An unexpected power problem at an aircraft manufacturer scrapped thousands of dollars in parts. A CNC engineer explains how a UPS (see photo) can influence manufacturing quality. (Also see tips for UPS selection, below.) A micro-controller had been plugged into....
The Wright brothers, recognized with building and controlling the world’s first successful human flight, sparked generations of engineering innovation in general aviation. Before attaining success, experimentation and trial and error were required, as the two studied the workings of bicycles and printing machinery to learn how to propel their ambitions. Trial and error with reliability and quality in today’s manufacturing processes won’t fly; reliable power quality is necessary to assure soaring operational results.
An airline manufacturer switched to a Falcon Electric online SSG Industrial-Grade UPS and improved manufacturing quality.
In the civilian aircraft industry, only a few manufacturers supply the market, primarily due to the high-level of technology and stringent manufacturing and safety standards demanded by the U.S. Federal Aviation Administration (FAA), Department of Transportation (DOT), and other governmental agencies. Today’s sophisticated manufacturing systems of lightweight composite materials combine technology, chemistry, cutting-edge equipment, and quality assurance.
The manufacturing floor includes networked computers, PLCs, robots, and other power sensitive microprocessor-based electronics that must operate reliably from utility power. The same power supplies motors, heavy machinery or welding processes that generate high levels of local power pollution. Uninterruptible power supplies (UPS) helped ensure reliable process control and safeguard day-to-day operations.
Major scrap: micro-controller loses quality data
At one major manufacturer, an unexpected power problem resulted in the scrapping of thousands of dollars worth of parts. The micro-controller responsible for monitoring a key stage in the parts manufacturing process had been plugged into an ineffective low-cost, line-interactive type UPS that “provided basic battery backup and minimal power conditioning. It was designed to protect computers in a home or office from power outages,” according to Rob Ayala, a CNC engineer at the plant.
“The line-interactive UPS would let transients and dirty utility power directly through to the micro-controller. This would frequently result in the loss of critical data communications, requiring the process to be shut down prior to completion,” Ayala says.
UPS topologies: online versus line-interactive
Ayala, with more than 20 years in the aerospace industry, Ayala began in a technical support role at another aviation company where he became familiar with UPS topologies.
“After we had solved the process power problem by deploying on-line UPSes at that particular cell,” Ayala explains, “we moved the line-interactive UPSes to backup non-critical computers. As time passed, we noticed that the batteries inside the on-line UPSes would last for several years, typically two to three times longer than the one to two year life we would get from the line-interactive systems. In my support role, I would frequently receive calls about malfunctioning line-interactive UPSes, and it was almost always the result of weak or dead batteries that had failed prematurely. In some of these cases we discovered the batteries had swelled up inside the UPS, making them impossible to replace. We then had to scrap the entire unit. Even though the on-line UPS cost us more, the overall cost of ownership was less.”
Online UPS topology attributes
To avoid more revenue drain from costly scrap, Ayala reconsidered UPS designs. “A true on-line topology UPS regenerates new, continuous, clean ac power. This process eliminates a much wider spectrum of power quality problems, maintaining the optimum power levels demanded by the equipment.” Ayala used the Falcon Electric SSG Industrial-Grade On-line UPS , several SSG 1.5 kVA units. The line, introduced in 2007, is rated to withstand environments with temperatures up to 55 °C.
“We have been using the SSG units for protecting our critical manufacturing processes for over six months without any problems,” Ayala says, and “We haven’t lost a single production run.”
Recommendations for UPS selection
Ayala offers the following UPS suggestions.
-Look at the company website for product selection;
-Check for industrial-grade ratings and designs;
-Call to gauge the knowledge and helpfulness of sales and technical staff; and
-Select an on-line UPS to ensure reliable operations for automated manufacturing or any industrial setting using microprocessor-based equipment for on the production floor.
Control Engineering provides
– Edited by Mark T. Hoske , editor in chief
Control Engineering System Integration eNewsletter
Register here and scroll down to select your choice of eNewsletters free .
Annual Salary Survey
After almost a decade of uncertainty, the confidence of plant floor managers is soaring. Even with a number of challenges and while implementing new technologies, there is a renewed sense of optimism among plant managers about their business and their future.
The respondents to the 2014 Plant Engineering Salary Survey come from throughout the U.S. and serve a variety of industries, but they are uniform in their optimism about manufacturing. This year’s survey found 79% consider manufacturing a secure career. That’s up from 75% in 2013 and significantly higher than the 63% figure when Plant Engineering first started asking that question a decade ago.