PC57.12.38 - Standard for Pad-Mounted-Type, Self-Cooled, Single-Phase Distribution Transformers 250 kVA and Smaller: High Voltage, 34 500 GrdY/19 920 V and Below; Low Voltage, 480/240 V and Below

Project Details

This standard covers certain electrical, dimensional, and mechanical characteristics and safety requirements of single-phase, 60-Hz, liquid-filled, self-cooled, pad-mounted, compartmental-type distribution transformers. These transformers are rated 250 kVA and smaller with high voltages of 34 500 GrdY/19 920 V and below for operation between one phase and grounded neutral and low voltage of 480/240 V and below. 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 all electrical and mechanical requirements of accessory devices that may be supplied with the transformer.

Standards Committee	PE/TR - Transformers
PAR Approval	2017-09-28
PARs	Approved PAR

Additional Resources Details

Historical Base Standard

C57.12.38-2014

Working Group Details

Working Group	Dist-WGC57.12.38 - Distribution - Pad-Mount 1 Self Cool <=250kVA Working Group
Standards Committee	PE/TR - Transformers
Society	IEEE Power and Energy Society
IEEE Program Manager	Malia Zaman
Existing Standards	Inactive-Withdrawn IEEE/ANSI C57.12.25-1990 - American National Standard for Transformers--Pad-Mounted, Compartmental-Type, Self-Cooled, Single-Phase Distribution Transformers with Separable Insulated High-Voltage Connectors: High Voltage (34 500 GrdY/19 920 Volts and Below) and Low-Voltage (240/120 Volts; 167 kVA and Smaller) This standard covers certain electrical, dimensional, and mechanical characteristics, and takes into consideration certain safety features of single-phase, 60-Hz, mineral-oil-immersed, self-cooled, pad-mounted, compartmental-type distribution transformers with separable insulated high-voltage connectors. These transformers are rated 167 kVA and smaller, with high voltages of 34500 GrdY/19 920 volts and below for operation between one phase and grounded neutral, and low voltages of 240/120 volts. These transformers are generally used for step-down purposes from an underground primary cable supply.
	Superseded IEEE C57.12.25 - Standard for Pad-Mounted, Compartmental-Type, Self-Cooled, Single-Phase Distribution Transformers with Separable Insulated High-Voltage Connectors; High Voltage, 34500 GrdY/19920 Volts and Below, Low Voltage, 240/120 Volts; 167 kVA and Smaller - Requirements This product standard covers certain electrical, dimensional, and mechanical characteristics and safety features of single phase, 60 Hz mineral oil filled, self-cooled, pad-mounted, compartmental type distribution transformer with separable insulated high-voltage connectors. Transformers are rated 167 kVA and smaller with high voltage of 34500 GrdY/19 920 Volts and below for operation between one phase and grounded neutral and low voltages of 240/120V.
	Superseded IEEE C57.12.38-2009 - IEEE Standard for Pad-Mounted-Type, Self-Cooled, Single-Phase Distribution Transformers; High Voltage, 34 500 GrdY/19 920 V and Below, Low Voltage, 240/120 V; 167 kVA and Smaller 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.
	Active IEEE C57.12.38-2014 - IEEE Standard for Pad-Mounted-Type, Self-Cooled, Single-Phase Distribution Transformers 250 kVA and Smaller: High Voltage, 34 500 GrdY/19 920 V and Below; Low Voltage, 480/240 V and Below 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.
	Active IEEE C57.12.38-2014/Cor 1-2016 - IEEE Standard for Pad-Mounted-Type, Self-Cooled, Single-Phase Distribution Transformers 250 kVA and Smaller: High Voltage, 34 500 GrdY/19 920 V and Below; Low Voltage, 480/240 V and Below - Corrigendum 1: Figure 1A 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.