This standard is intended for use as a basis for determining performance, interchangeability, and safety of the equipment covered, and for assisting in the proper selection of equipment. It covers certain electrical, dimensional, and mechanical characteristics and takes into consideration certain safety features of three-phase, 60 Hz, mineral-oil-immersed, self-cooled, pad-mounted, compartmental-type distribution transformers with separable insulated high-voltage connectors. These transformers are rated at 2500 kVA and smaller, with high voltages of 34 500 Grd Y/19 920 V and below and with low voltages of 480 V and below. These transformers are used generally for step-down purposes from an underground primary cable supply. Connector and terminal arrangements for both radial-feed and loop-feed systems are included.

Withdrawn Standard. Withdrawn Date: Mar 06, 2000. No longer endorsed by the IEEE. IEEE Std C57.12.26-1992 (Revision of ANSI C57.12.26-1987) IEEE Standard for Pad-Mounted, Compartmental-Type, Self-Cooled, Three-Phase Distribution Transformers for Use With Separable Insulated High-Voltage Connectors (34 500 Grd Y/19 920 V and Below.