Custom gen-set controls and monitoring systems

Diesel Progress North American Edition, Nov, 1997 by Mark McNeely

Computerized control systems include ruggedized industrial components that are PLC- or PC-based, with local or remote monitoring, control and data logging of all system functions, be they engines, generators, pumps or other driven equipment. "All of our designs are to customer specifications, but we do integrate a certain amount of standard componentry," said John Karp, national sales manager for AEC Engineering. "The PLCs and industrial computers that we use are commercially available, however, for various shutdown and other safety features we do design and build up our own circuit boards."

A choice of digital, analog and/or fault indicator configurations are available, Karp said.

"Our remote monitoring currently consists primarily of standby gen-sets at municipal sites" he said. "Our strength in the remote monitoring area is in writing easy-to-understand software, with on-screen symbology utilizing industry standard symbols wherever possible."

Communications between the system and the remote site can include a modem via land line telephone, cellular or radio telemetry link. Data logging intervals have included less than every second, with an averaged data set saved every 1 to 30 minutes to conserve memory space. Every 1 to 30 days, the local site relays data to the central monitoring system. In the event of any function going out of original specification, the data is not compressed and is transferred immediately to the monitoring site, allowing analysis and proper corrective action to be implemented, Karp said.

Central monitoring systems, capable of monitoring over 100 remote sites, have also been developed by AEC. The sites work in conjunction with miniaturized PCs or PLCs on the systems, which are housed in shock-mounted, sealed enclosures. Local readouts and field diagnostic units are also available.

"AEC's ruggedized equipment emanates from our work with diesel-powered earth screening machinery," said Karp. "We've built thousands of controls that were designed to be bolted to the bell housings of diesel engines. And from that experience evolved our manufacturing of controls and data acquisition equipment for other industrial applications, as well as the military."

Another area where AEC has developed expertise is in assembly of marine, construction and industrial wiring harnesses. "Often, an engine fault or failure can be traced to a wiring failure, which is the result of the wire harness or insufficient vibration isolation," Karp said. "Such faults can be expensive and difficult to trace, making quality harnesses a good investment."

Components can be supplied to military specification for corrosion resistance, fire retardance and flexibility. All are provided with high-voltage jacket insulation as standard. Each harness is tested before shipment.

The company is a UL-certified manufacturer of control systems and UL-listed engine-generator control systems are available.