Under section 404.14(A), what is the maximum load an alternating-current general-use snap switch supplying a one-horsepower motor is permitted to control?

The maximum load an alternating-current general-use snap switch is permitted to control, as outlined in section 404.14(A), is indeed 80% of the ampere rating. This standard is significant for ensuring the safety and longevity of electrical devices. By allowing only 80% of the ampere rating for the control of motors, it provides a safety margin that accounts for overload conditions or potential increases in current that can occur during motor startup or under certain operational conditions. This prevents overheating of the switch and reduces the risk of electrical fires or equipment damage.

It's essential to recognize that the other percentage options do not consider this safety factor. For example, controlling the maximum load at 100% of the ampere rating could lead to insufficient capacity to handle peak currents during the operation of the motor, thereby compromising safety. Therefore, adhering to the 80% standard is a best practice in electrical code and contributes to safe and reliable motor operation.