This document provides the methodology to be used by vendors and third party independent laboratories in the formation of a telecommunications energy efficiency ratio. The requirements and definitions in this document are for DC power plant Inverters that are deployed in the telecommunications industry. This supplemental standard represents one part of the larger ATIS suite of standards concerning Telecommunications Energy Efficiency (ATIS-0600015.10.2015). This supplemental standard (ATIS-0600015.10.2015) specifically addresses DC Power plant Inverters and is to be used in conjunction with ATIS-0600015.2013. Purpose This document provides a set of definitions@ requirements@ and guidelines for calculating the Telecommunications Energy Efficiency Ratio (TEER) of DC Power plant Inverter products. The test methodology employed to verify the power consumption@ used as part the TEER calculation@ is specific to power equipment and therefore differs from ATIS-0600015.2013.