Red Seal Industrial Mechanic (Millwright) Practice Exam

How do you determine the correct size of a motor for an application?

1. Based on its color and design.

2. Based on load requirements, duty cycle, and application type.

3. Using a standard dimension chart.

4. By matching it with similar machines.

The correct answer is: Based on load requirements, duty cycle, and application type.

Determining the correct size of a motor for an application primarily involves understanding the specific requirements of that application, which includes assessing the load requirements, duty cycle, and the type of application. Load requirements refer to the amount of work the motor needs to perform, often indicated in terms of torque or horsepower needed to drive the equipment. The duty cycle is essential as it describes the duration and frequency of the motor's operation. For instance, a motor used in a continuous duty application would require a different rating compared to one used intermittently. Understanding these elements helps in selecting a motor that can operate efficiently and reliably without overheating or exceeding its operational limits. The type of application also plays a crucial role, as different applications such as pumps, conveyors, or fans might demand motors with varying characteristics. In contrast, choosing based on the motor's color and design does not provide any meaningful insight into its operational capabilities or suitability. Similarly, the use of a standard dimension chart may not account for the specific loading or application conditions, and merely matching a motor with similar machines does not ensure that it will perform adequately in a different operational context. Therefore, a comprehensive understanding of load requirements, duty cycle, and application type is vital in making an informed decision when selecting the