How To Wire a Toggle Switch?
This is a quick and easy guide on how to wire your toggle switch.
What is a toggle switch?
A toggle switch is a type of electrical switch that has a leveler/ handler that is "toggled" back and forth to open or close an electrical circuit. This is a very simple switch that works in many applications, from household lights to headlights in a car. The primary function of a toggle switch involves flipping the lever in one direction to turn on the device and moving it in the opposite direction to turn it off.
Toggle switches are commonly used as light switches in homes and buildings. In vehicles and boats, toggle switches are used on dashboards and control panels to operate lights (headlights, interior lights, fog lights), windshield wipers, and other electrical accessories. Some smaller vehicles may use a toggle switch as part of the ignition system to activate the ignition circuit or as a kill switch to shut off the engine for safety immediately. Toggle switches are also common as an on/off control for industrial machinery and equipment. They can also be used in aircraft control systems.
Types of toggle switches
- Single-Pole Single-Throw (SPST): The simplest type, which connects or disconnects one circuit.
- Single-Pole Double-Throw (SPDT): Can connect one input circuit to one of two output circuits. This subtype of a toggle switch typically has three wires.
- Double-Pole Single-Throw (DPST): Controls two circuits with a single action but doesn't allow switching between circuits.
- Double-Pole Double-Throw (DPDT): Can control two circuits and switch between two output options. This type also commonly has three wires.
Steps to Wire a Toggle Switch
Tools and Materials
- Toggle switch
- Wire strippers
- Screwdriver
- Electrical tape
- Wires
- Wire connectors (if necessary)
-
Identify the Toggle Switch Pins
A basic toggle switch has two or three terminals. The two-terminal switch is a simple on-off switch, while the three-terminal one usually includes an on-off-on configuration.
2. Prepare the Wires
Strip about 1/2 inch of insulation from the ends of the wires connected to the switch. If you're replacing an old switch, remove it by disconnecting the wires.
3. Connect the Wires to the Switch
- For a two-terminal switch, attach one wire to each terminal. It doesn't typically matter which wire goes to which terminal in a simple on-off toggle switch.
- For a three-terminal switch, the center terminal is usually the common terminal that gets connected to your power source. One of the outer terminals is connected to the load (the device you want to control). The other outer terminal can be used if you're wiring the switch for an on-off-on configuration.
4. Secure the Connections
Make sure the wires are firmly attached to the switch terminals. You can use a screwdriver for screw terminals or properly crimp any spade connectors.
5. Insulate the Connections
If there's any exposed metal from the connections, wrap them with electrical tape to prevent short circuits.
6. Mount the Switch
Secure the toggle switch in its desired location. This could be on a panel, in a box, or any other suitable place.
7. Test the Switch
After ensuring all your connections are secure and insulated, turn the power back on to test the switch. The device or light you control should turn on and off as you toggle the switch.
Does a toggle switch need to be grounded?
Toggle switch needs to be grounded when:
- It is mounted on a metal enclosure
- In electrical systems where the grounding of circuits is required
- In wet and damp locations
- In circuits involving sensitive electronic components, such as industrial control systems or aerospace equipment
The toggle switch does not need to be grounded:
- If the switch is mounted to plastic or a non-conductive enclosure
- In simple low-voltage DC applications
Cables For Toggle Switches
Cables for toggle switches depend on particular applications where the switch is used. NM-B is the most common cable used with toggle switches in residential applications. The size in which it is being used is 14 AWG for 15-amp circuits and 12 AWG for 20-amp circuits. Other cables that can be used with toggle switches in residential wiring are MC metal-clad cables when the cable needs mechanical protection, THWN, and UF-B for outdoor light switches.
In other conditions, toggle switches can be used in combination with automotive primary wire, marine grade wire, aerospace cables, and others.
