This project replaced two antiquated medium voltage substations 4160/480V – one inside the prison and one outside the prison wall – with a redundant medium voltage loop around the exterior of the Indiana State Prison facility. In a previous project, the first of six medium voltage switches were installed on the exterior of the prison and this project completed the buildout of the medium voltage loop with an additional five switches. Each switch has two medium voltage cable paths, allowing redundancy around the facility electrical distribution system.
From each switch there were 4160/480V transformers placed in strategic positions inside and outside of the prison, along with 480V distribution panels to serve groupings of buildings. Each building has its own 480V feeder installed and fed from the distribution panelboards. The project was a challenge to keep the prison functioning 24/7 without outages, while also avoiding the existing 100-year-old underground utilities.