What is a timer switch?

A timer switch is designed to control the operation of lights or appliances based on pre-set times. This functionality allows users to program the switch to turn devices on or off automatically, which can enhance energy efficiency and provide convenience. For instance, you could set outdoor lights to turn on at sunset and off at sunrise, or program a fan to run for a specific period of time each evening.

The other options do not accurately represent a timer switch. For example, while a device that measures electrical consumption would certainly be beneficial for monitoring energy usage, it does not perform the function of turning devices on or off based on a timer. Similarly, a type of switch intended solely for heavy-duty appliances does not encompass the broad versatility of timer switches, which can be used for various household devices. Lastly, a switch that operates only through remote control describes a different functionality that does not inherently include the timer function, which is about pre-set scheduling rather than remote operation.