VMR South Extension 1

Valley Metro Rail South Central Light Rail Extension

Phoenix, AZ

Phoenix, AZ



The Valley Metro Rail South Central Light Rail Extension will connect with the current light rail system in downtown Phoenix and operate south to Baseline Road. The project includes a hub in downtown Phoenix, 5.5 miles of at-grade trackway, nine at-grade stations, traction power substations, signal buildings and upgrades to existing system elements to accommodate the extension. The extension will result in a reduction of traffic congestion and air pollution throughout the valley. Additionally, it will provide a link to Arizona State University, downtown Phoenix and Phoenix Sky Harbor International Airport. This new line’s daily ridership count is estimated at 6,690 people and it will serve 128,000 employees in the region. The South Central Light’s construction will take place in early 2020, and the new line will begin service in 2023.

Triunity performed the 480/208V and 240/120V electrical power and lighting designs for (5) Traction Power Substations and (3) Signal Buildings.  The facilities included battery back-up systems operating at 12V and 125 VDC and a transfer switch with receptacle for connecting a mobile diesel generator in the event of an extended utility outage.  Redundant air conditioners were installed to improve reliability.  Interior and exterior pathway lighting levels were modeled using AGI32 software.  Automatic lighting controls incorporated photocells with manual override. New electrical services were coordinated with the power utilities and a preliminary short circuit study was developed to guide the selection of distribution equipment.