Approved IEEE Draft Standard for Overhead Type Distribution Transformers, 500 kVa and Smaller: High Voltage, 34 500 Volts and Below; Low Voltage, 7970/13 800Y Volts and Below (Revision of IEEE C57.12.20-1997) Superseded by C57.12.20-2005

This standard covers certain electrical, dimensional, and mechanical characteristics and safety features of single- and three-phase, 60 Hz, mineral-oil-immersed, self-cooled, overhead-type distribution transformers 500 kVA and smaller, high voltages 34 500 V and below and low voltages 7970/13 800Y V and below.