NEIEP Mechanics Practice Exam

Switches are generally rated by the maximum ____ when open and the maximum ____ when closed.

1. Current, Voltage

2. Voltage, Power

3. Voltage, Current

4. Power, Current

The correct answer is: Voltage, Current

Switches are rated based on their electrical capabilities to ensure safe and effective operation within a circuit. The first part of the rating, concerning the maximum voltage when the switch is open, refers to the highest voltage the switch can withstand without arcing or breaking down. A switch must be able to handle this voltage when it is in the open position, as this is the state when there is no current flow and requires maintaining insulation properties to prevent electrical failure. The second part of the rating, referring to the maximum current when the switch is closed, indicates the highest current the switch can carry without overheating or being damaged. When a switch is closed, it completes the circuit allowing current to flow, so it is crucial that the switch can handle this current safely. Understanding these ratings is essential for selecting the appropriate switches for electrical applications, as using a switch beyond its rated voltage or current can lead to failures or hazardous conditions.