This standard describes the installation and maintenance procedures for single- and three-phase general purpose dry-type distribution and power transformers and associated accessories rated 600 Volts AC or less, and 0.25 kVA or more. This publication applies to indoor and outdoor, ventilated and non-ventilated, two-winding transformers used for supplying power, heating, and lighting loads for commercial, institutional, and industrial use in nonhazardous locations