I belive that Shoreline Model Raceways was the first club to use XLR connectors on all of our tracks. Pin 1 is Black, pin 2 is White and pin 3 is Red. After a major race that was held at Area 51 Raceway the visiting drivers were so impressed that they went home and added XLR connectors to their own tracks. As far as I know all of the tracks that use XLR connectors have them wired the same way.