Final answer:
The standard polarity of transformers like a 14.4 kVA transformer, which are typically less than 200 kVA, is generally additive, but can vary depending on specific design, so checking the data sheet or conducting a polarity test is advised.
Step-by-step explanation:
The standard polarity of a transformer is a characteristic that defines the phase relationship between the input (primary) and output (secondary) voltages. For a transformer with a power rating of less than 200 kVA, such as a 14.4 kVA transformer, the standard polarity is typically additive for small distribution transformers. This means when the primary and secondary windings are excited by their respective voltages, if the ends of the windings marked with an 'X' for the secondary and an 'H' for the primary are both positive at the same instant, the polarities are considered to be in phase or additive. However, the polarity can be subtractive in certain designs, and one should refer to the transformer's data sheet or perform a polarity test to determine its exact polarity.