Section 2: Traffic Signal Controllers for Railroad Interconnected Intersections
TxDOT traffic signals may operate on traffic signal controllers from various manufacturers in the TxDOT Districts and there will be manufacturer-specific variances in the controller configuration and programming. However, all TxDOT controllers shall meet NEMA TS2 standards. Traffic signal controllers interconnected to grade crossings for the purpose of railroad preemption shall have a minimum of six preemptors available for railroad preemption. The contractor or traffic signal technician shall assign preemptors based on the railroad circuit configuration.
ATC Controllers
Traffic signal controllers that conform to the NEMA ATC specification provide robust logic processing features and the ability to map controller inputs that can be assigned in the logic processor. These features are required when considering the use of a passive-style railroad interface as defined in Chapter 5, Section 3.