Step-Down Transmission Substation : These substations are located at switching points in an electrical grid. They connect different parts of a grid and are a source for subtransmission lines
US Department of Labor, Electric Power eTool: Glossary of Terms, Occupational Safety & Health Administration OSHA, Washington, D.C., USA 2010. https://www.osha.gov/SLTC/etools/electric_power/gl ossary.html, (OSHA/ Electr Pwr - Amer) {618}