Dist-WGC57.12.38 - Distribution - Pad-Mount 1 Self Cool <=250kVA Working Group

This standard covers certain electrical, dimensional, mechanical characteristics and safety requirements of single-phase, 60 Hz, liquid-filled, self-cooled, padmounted, compartmental-type distribution transformers. These transformers are rated 167 kVA and smaller, with the high voltages of 34 500 GrdY/19 920 V and below for operation between one phase and grounded neutral, and low voltage of 240/120 V. These transformers are generally used for step-down purposes from an underground primary cable supply. This standard covers the connector, bushing, and terminal arrangements for radial or loop feed systems. This standard does not cover the electrical and mechanical requirements of any accessory devices that may be supplied with the transformer.

Certain electrical, dimensional, and mechanical characteristics are covered in this standard, and certain safety features of single-phase, 60-Hz, mineral-oil-immersed, self-cooled, pad-mounted, compartmental-type distribution transformers are taken into consideration. These transformers are rated 250 kVA and smaller with high voltages of 34 500 GrdY/19 920 V and below and with low voltages of 480/240 V and below. These transformers are generally used for step-down purposes from an underground primary cable supply. The connector, bushing, and terminal arrangements for radial or loop feed systems are covered in this standard. The electrical and mechanical requirements of any accessory devices that may be supplied with the transformer are not covered in this standard.

Identified in the 2014 published version of IEEE Std C57.12.38 is an error. Tw0 dimensions were provided for the high-voltage bushing height above the base of the transformer. The lower dimension (597+114/-13) should have been designated as being for units 167 kVA and 250 kVA only. The error is corrected in this corrigendum.