A Toggle Switch SPDT (Single Pole, Double Throw) is a type of electrical switch that has three terminals and can be used to control the flow of electrical current in a circuit. Here’s what SPDT toggle switch means and how it operates:
**1. Single Pole:** The “Single Pole” part of the name indicates that the switch has only one common connection point. In the context of a toggle switch, this means there is one terminal (pole) that is used for switching the current.
**2. Double Throw:** The “Double Throw” part of the name indicates that the switch has two possible positions for the switch lever, each corresponding to a different connection configuration. In other words, there are two possible ways the switch can be set to control the flow of electrical current.
The SPDT toggle switch typically has three terminals or connections:
**1. Common (COM):** This is the central terminal of the switch and represents the single pole. The common terminal is the point where the switch lever connects electrically to either of the two throw terminals.
**2. Throw 1 (NO – Normally Open):** One of the throw terminals is connected to the common terminal when the switch is in one position, creating an electrical connection. When the switch is flipped to the other position, the connection is broken, and no current flows between the common and throw 1 terminals.
**3. Throw 2 (NC – Normally Closed):** The other throw terminal is connected to the common terminal when the switch is in the opposite position from the one mentioned above, creating an electrical connection. When the switch is flipped to the first position, the connection is broken, and no current flows between the common and throw 2 terminals.
**Operation:** When you flip the toggle lever of an SPDT switch, you are essentially choosing between two different electrical paths. Depending on the position of the lever, the common terminal is connected to either the throw 1 or throw 2 terminal, creating one of two possible electrical connections. This makes SPDT switches versatile and suitable for applications where you need to select between two different options.
SPDT toggle switches are commonly used in a wide range of applications, including but not limited to:
– Control of lights and fans in household appliances.
– Selection between two power sources (e.g., battery or external power supply).
– Changeover between two different circuits or devices.
– Signal routing in audio equipment.
– Control of motors in machinery and robotics.
These switches provide a simple and reliable way to switch between two different electrical paths, and they are available in various sizes and designs to suit different applications.