Common use of MAJOR COMPONENTS Clause in Contracts

MAJOR COMPONENTS. The SS-RTSP project employed the TSP system developed by ▇▇▇▇▇▇. It has three major subsystem components, including an in-vehicle subsystem, road-side subsystem, and center subsystem. Figure 3-1 illustrates the subsystems in the field. When an equipped transit vehicle approaches a TSP-enabled intersection, the in-vehicle device communicates with the road-site antenna. A reader sends the transit vehicle’s electronic identification and trip information to the traffic signal controller for the transit vehicle’s eligibility evaluation. If the transit vehicle is qualified to receive TSP and no other TSP has been issued in the current signal control cycle, a TSP treatment may be provided to reduce delay of the transit vehicle (McCain Traffic Supply 2004). The field equipment is connected with the center subsystem and can be remotely monitored, debugged, and updated. A transponder installed on the front end of the transit vehicle provides the coach number, route number, trip number, and transit system operator identification (such as Community Transit or Metro). The road-side subsystem includes radio frequency (RF) antennas mounted upstream of the traffic signals on mast arms, power sources for reader units, and the Transit Priority Request Generator (TPRG). A TPRG contains a microprocessor and a communication device connected with the traffic signal controller via 24 VDC logic inputs.