Voltage supplied to a motor may vary from the rated voltage by what percentage?

The correct answer identifies that the voltage supplied to a motor may vary by plus or minus 10% from the rated voltage. This allowance is important in the context of electrical systems, where components, particularly motors, need a certain level of voltage to operate efficiently and reliably.

Many motors are designed to tolerate variations in supply voltage to a degree, recognizing that fluctuations can occur due to various factors like load changes or line losses. Operating within a +/- 10% range helps ensure that the motor can perform its intended functions without overheating or failing due to insufficient voltage.

Higher tolerances, such as +/- 15% or more, can lead to operational inefficiencies, increased wear, and potential damage to the motor in the long run. Understanding this limit is vital for technicians when evaluating the performance and health of HVAC systems, especially those reliant on electric motors, such as compressors in heat pumps. Ensuring voltage remains within this specified range is key to maintaining system longevity and effectiveness.