Toggle Switch SPDT - ON-OFF-ON

The Toggle Switch SPDT - ON-OFF-ON provides three-position control for marine electrical circuits that need to select between two outputs or operating functions. Its single-pole, double-throw configuration is commonly used for combining navigation lights or an anchor light with independent bulbs.

With maintained ON positions on both sides of a center OFF position, this switch gives you positive control over two separate circuit paths. The three-terminal design and quick-connect tabs make it suitable for compatible marine wiring applications.

Maintained vs. Momentary Switches

• Maintained: Stays in the selected "On" or "Off" position until you flip it back.
• Momentary (indicated by parentheses like (On)): Returns to its default position via a spring as soon as you let go; used for temporary actions like horns or starter buttons.

Common Configurations

• SPST (Single Pole, Single Throw): A simple two-terminal switch used to control one circuit.
• SPDT (Single Pole, Double Throw): A three-terminal switch that can alternate power between two different circuits or accessories.
• On/Off/On: A three-position switch that can select between two circuit paths with an OFF position in the center.

Three-Position Circuit Control

The ON-OFF-ON action provides two maintained ON positions separated by a center OFF position. This configuration allows one switch to select between two circuit paths and is commonly used in marine navigation-light applications with independent bulbs. Blue Sea Systems lists SPDT ON-OFF-ON switching for navigation lights using independent bulbs. :contentReference[oaicite:0]{index=0}

Quick-Connect Terminals

Three 0.25-inch (6.35 mm) quick-connect tab terminals provide the connections required by the SPDT configuration. The switch should be wired using appropriately sized fuses and wire for the specific electrical load.

Specifications

Marine Navigation-Light Applications

The ON-OFF-ON SPDT configuration is particularly useful for selecting between navigation-light and anchor-light circuits when the lights use independent bulbs. Blue Sea Systems identifies this switching arrangement as a common navigation-light application. 

Electrical Ratings

The switch is rated for up to 15A at 12V DC and 125V AC, and up to 10A at 250V AC. Maximum amperage ratings depend on using appropriately sized fuses and wire for the specific application.