What does SPST stand for in relation to electrical switches?

SPST stands for Single Pole Single Throw, which describes a type of electrical switch that has one input (the pole) and one output (the throw). This means that the switch can either connect or disconnect a single circuit. When the switch is in the 'on' position, it allows electrical current to flow through, completing the circuit. Conversely, when it is in the 'off' position, it breaks the circuit, stopping the flow of electricity. This type of switch is commonly used in simple applications like household lighting controls and other basic electrical devices, making it a fundamental concept in electrical circuits and HVAC control systems. Understanding SPST switches is essential for HVAC technicians, as they often deal with various switch types in their work.