Supplying aircraft fueling systems to U.S. military bases, Bay Associates of Virginia Beach, VA, performs under an enormous amount of pressure—literally. Using GE Intelligent Platforms ’ PACSystems RX3i controllers and Series 90 PLCs and coupled with Proficy CIMPLICITY HMI/SCADA software, Bay designs unique, high-performance systems that instantaneously respond to the infinitely variable demands and pressure conditions associated with aircraft fueling.
The largest aviation fueling system supplier in the world, Bay’s Fueling Division sells valves, controls, and equipment used in storage, transfer, and dispensing of fossil fuels for military aircraft. Over the past several years, many major airports and military bases have changed their methods of fueling aircraft from tank-type vehicles loaded at storage facilities away from the apron or ramp, to automated or “hydrant” fueling systems, eliminating the need for vehicular storage and transport to the aircraft.
Hydrant fueling systems typically feature a minimum of two tanks, one dedicated to receiving fuel and the other dedicated to dispensing fuel. Both tanks incorporate pump houses with two to 10 identical fueling pumps handling individual capacities from 600 to 1,200 gallons per minute. Corresponding capacity filter separators, control valves, and instrumentation for starting and stopping the pumps are incorporated as determined by flow rate demands. Bay uses contactors and electrical components from GE Industrial and GE flow meters from GE Sensing for these highly important tasks.
“Each PLC is programmed to react to pressure conditions within a loop system by communicating to the lead pump,” said Robert Boseman, president of Bay Associates. “When the pressure drops, the PLC brings on the lead pump to adjust the pressure according to demand.” The PLC follows a sequence to bring on additional pumps. If the system is issuing 600 gallons of fuel and only getting 50 gallons on return, additional pumps come online to satisfy the demand, or go offline in the case of over supply.
Depending on I/O specifications, a GE Intelligent Platforms PACSystems RX3i controllers, Series 90-30 or Series 90-70 PLC hardwired to field devices, I/O modules, and, for “hot standby” applications, a Genius bus, provides communication from the I/O racks to the CPU. Every system incorporates a redundancy system for downtime production. Bay’s latest hydrant control systems uses the PACSystems RX3i to monitor and control 500 I/O points -- 90% digital I/O and 10% analog I/O.
Proficy CIMPLICITY software is used for information exchange through a desktop computer interface to run diagnostics or check field devices like pressure and flow transmitters, showing historical and trend information. With this information operators can understand how the system is running and can run diagnostics, recreate fault conditions, and keep the system running more efficiently.