What is the proper connection type to install a transformer rated at 12470GrdY/7200-120/240 to a system voltage of 12470 volts?

The correct connection type for a transformer rated at 12470GrdY/7200-120/240 when connecting it to a system voltage of 12470 volts is a wye connection.

A wye configuration is ideal in this scenario because it allows for the connection of the high voltage side of the transformer directly to the 12470-volt system. In a wye connection, one end of each coil is connected to a common neutral point, which is often grounded. This configuration permits the system to handle line-to-neutral and line-to-line voltages adequately and provides a stable ground reference for the transformer system.

Moreover, wye configurations are advantageous for balanced loads and help in reducing voltage imbalances across the phases. When working with a system that operates at higher voltages, as in this case, the wye connection permits easy access to dual voltage taps (in this case, 120/240 volts on the low side), making it versatile for various load requirements.

Other connection types may not provide the same level of compatibility. Delta connections don't offer the same grounding and neutral availability, which can lead to complications in a grounded system. Open delta configurations are typically used for reducing costs when three transformers are not available, but in this