Which of the following is not typically listed on the transformer nameplate?

• A. Impedance
• B. Frequency
• C. Color
• D. Primary and Secondary Voltages

Answer: (C)

Transformers carry information on the nameplate that’s needed to install and operate them safely and correctly: primary and secondary voltages show the connections you must make, impedance (often given as a percentage) helps with voltage regulation and fault current calculations, and the frequency indicates the system speed it’s designed to run at. These items are all electrical specifications used for proper sizing and integration. Color, on the other hand, is not a functional electrical parameter and isn’t part of the required electrical data on the nameplate. It may be used for identification or cosmetic purposes, but it doesn’t affect how the transformer is connected or operated. So, color is not typically listed on the transformer nameplate.