Low voltage dry-type distribution transformer means a distribution transformer that has an input voltage of 600 V or less, is air-cooled, and not used oil as a coolant. The Square D Energy Efficient transformer offering includes all of the popular options including low temperature rise, 115 °C and 80 °C, and aluminum or copper windings. These transformers are part of a complete line of Lean Power products from Schneider Electric. Available with aluminum or copper windings and 150°C or 115°C Rise with 220C insulation system. This Energy Efficient Transformer is a 1 phase, 75kVA, that has a primary Voltage of 240 x 480V and a secondary voltage of 120/240V. The Enclosure has a NEMA 2 rating and has a box number of 21D with a insulation temperature of 220 °C. The unit is made of aluminium with a 150 °C temperature rise. Units are specifically designed to function with other Square D equipment; inrush is coordinated to meet identified breaker trip curves, and IZ levels allow for let through current to match AIR levels of panelboards.