Abstract: An integrated control and monitoring system for airport avionics is made single-point-of-failure impervious by continuously operating pairs of parallel-connected concentrators, Remote Master Workstations and Remote Slave Workstations, and a pair of independent LANs each connecting one of the concentrators of a pair to the Remote Workstations. Each concentrator of a concentrator pair, while in secondary status, monitors the operation of the concentrator in primary status, and whenever it observes a failure of communication will assume primary status and continue to allow ICMS to function in a normal manner. Likewise, another Remote Master Workstation automatically assumes Remote Master Workstation status if it fails to see an operational active master station on the network.

Abstract: A constant-current regulator for high-powered airport lighting loops combined a ferroresonant transformer and a digital programmable logic device to provide a versatile, software-modifiable current control for power transfer throughout a range of about 30 kW to 50 kW with uniformly good power factor and low harmonics without switching winding taps, and without requiring oil cooling.