C57.12.23-1992 - IEEE Standard for Transformers--Underground-Type, Self-Cooled, Single-Phase Distribution Transformers with Separable, Insulated, High-Voltage Connectors; High Voltage (24 940 GrdY/14 400 V and Below) and Low-Voltage (240/120 V, 167 kVA and Smaller) | IEEE Standard | IEEE Xplore