Choosing Wire Connector Types
All types of wire connectors are designed to make connections between electrical wires and prevent the wires from contacting anything that could create a short. Wire connectors are necessary for making any wiring connections, including installation of electrical receptacles, light switches, ceiling fans and light fixtures.
Wire connectors have minimum and maximum wire gauges or diameters they can handle and a maximum number of wires they can accept. For example, a wire connector might have a minimum capacity of two 14-gauge wires, indicated as “2 #14 AWG,” and a maximum capacity of four 12-gauge wires, indicated as “4 #12 AWG.”
Other specifications might include:
- Maximum voltage, amperage and temperature capacities
- Water resistance
- Suitability for indoor or outdoor use
- Suitability for direct burial without an electrical box
You also need to know the type of wire you’re working with. Standard wire connectors are for use with copper wire only. Don’t use them with aluminum wire. Aluminum wire requires a connector designed for the material.
Connecting aluminum wires or connecting aluminum wires to copper wires creates a safety hazard unless you use a type of wire connector specifically for use with aluminum wires.
Caution When Working With Wire Connectors
Use this information on types of wire connectors only as a general guide. Connector types and uses might vary by manufacturer or local code.
- Some installations require a licensed professional electrician.
- Follow electrical codes for your area, including requirements for permits and inspections.
- Follow the manufacturer’s installation instructions, gauge, voltage and amperage limits, enclosure requirements, etc.
- The power to a circuit or device must be off before work begins.
- A non-contact voltage tester can verify the power is off.
- Contact a licensed electrician if you have any doubts about the connections or your home wiring doesn’t appear compatible with the planned changes.
- Most connections need to be enclosed in an electrical box.
The # symbol indicates the American Wire Gauge (AWG) measurement. Lower AWG numbers indicate a wire with a larger diameter. See our guide to wire gauge sizes.
Twist-On Wire Connectors
Most electrical wire connectors for residential use are variations of the twist-on connector. The standard twist-on wire connector is a cap with ridges on the barrel and a wire spring on the inside.
- Standard twist-on connectors are the most economical.
- Ridges create grip to twist the connector onto a set of wires.
- As the connector twists, the spring grips and holds the wires.
- Most models work with solid and stranded wire.
- Twist-on connectors are typically reusable if not damaged.
- Common uses include installing receptacles, switches, lights, ceiling fans and other hard-wired devices.
Wing Wire Connectors
Wing wire connectors function like twist-on connectors but have tabs on the barrel to make installation and removal easier.
- This type of wire connector can be a quick option that’s more comfortable to use than standard twist connectors.
- The tabs allow better tightening.
- They typically work with solid and stranded wire.
- Undamaged wing wire connectors are typically reusable.
- These connectors work for installations such as wiring receptacles, light switches, and light fixtures.
Underground and Waterproof Wire Connectors
Underground and waterproof wire connectors are specialized types of twist-on wire connectors. Many models are designed for underground use and use in wet conditions but check the specifications for your connectors.
- Silicone sealant in the connector and flanges around the opening protect wiring from corrosion, dust and moisture.
- Some underground connectors are suitable for direct burial — direct contact with the soil.
- Underground and waterproof connectors typically work with solid and stranded wire.
- This type of wire connector isn’t reusable.
- Residential uses include installation of exterior outlets, light fixtures and sound systems.
- Underground wire connectors are suitable for below-ground wiring in applications such as landscape lighting.
Some direct-bury connectors have a two-part design, with a twist-on wire connector that fits inside a sealant-filled protective tube. The exterior tube and sealant protect the connection.
Push-In Wire Connectors
Inserting wires into push-in wire connectors creates quick and easy connections.
- A clear housing shows if wires are fully inserted and some connectors have a port to test the connection.
- A free port on a connector allows the installer to add to the connection without redoing it.
- Push-in connectors are best for solid wire, but work with some stranded wire.
- Some models of push-in connectors used for solid wire are reusable on solid wire with the same gauge or larger.
- Push-in connectors aren’t reusable if they’ve held stranded wire; strands can lodge in the device and prevent a good connection.
- Push-in connectors typically work for many of the same applications as twist-on connectors.
Aluminum/Copper Wire Connectors
While most wire connectors are suitable only for copper wire, Al/Cu wire connectors (aluminum/copper wire connectors) can make connections with aluminum and copper wire.
- Some Al/Cu connectors can connect aluminum to aluminum, copper to aluminum and copper to copper.
- This type of wire connector has ports that keep the wires separated and contains a sealant to reduce oxidation of the wires.
- Connections require a torque screwdriver to secure the wires by tightening set screws to a specific tightness or torque.
- Al/Cu connectors aren’t reusable.
You can also find specialized, single-use twist connectors designed to connect aluminum to copper wiring. However, these hand-tightened connectors can be difficult to tighten to the correct torque.
Electrical work prior to the 1980s might include aluminum wires. Aluminum wire often has a dull gray color and should have “aluminum” or the letters “AL” printed on the wire jacket.
Wire Connector Types: Key Points
Wire connectors allow secure connections between electrical wires, with different types of wire connectors fitting different uses. Here are the main points to remember:
- All electrical work must comply with electrical codes and might require a licensed pro, permits and inspections.
- Wire connectors are suitable for maximum and minimum wire gauges and different numbers of wires.
- Wire connectors have specific voltage, amperage and temperature ratings.
- Most wire connectors are for use with copper wires.
- Twist-on wire connectors are common for indoor use and include ridged connectors and winged connectors with flanges for easy use.
- Underground and waterproof wire connectors are for specific outdoor applications.
- Push-in wire connectors are some of the easiest to use.
- Al/Cu wire connectors are required when working with aluminum wires.
- Always defer to the connector manufacturer’s specifications and instructions.
Shop Lowes.com to find wire connectors for any type of electrical connection, as well as the tools and materials necessary for the work. Or visit your local Lowe’s and talk to a Lowe’s Red Vest associate. They can help you find the right wire connector types for different jobs as well as tools and supplies to do the work right.
FAQ on Types of Wire Connectors
Use the answers to some common questions to better understand wire connector types and applications.
How Do I Know Which Wire Connector to Use?
Different types of twist-on connectors are common for interior household applications like installing light fixtures. Outdoor wiring requires outdoor-rated connectors and might require underground or waterproof connectors. Connecting aluminum wires requires a special wire connector designed for the material. Always defer to local codes and manufacturer’s instructions when choosing a wire connector for a specific use.
Can Wire Connectors Be Used With All Wire Types?
No, typical wire connectors are only suitable for joining copper wires. Connecting aluminum wires or connecting aluminum wires to copper wires each requires a connector specifically designed for the application.
How Do I Remove Wires From Push-In Connectors?
Hold a wire in one hand and the connector in the other. Hold the connector in place while you pull and twist the wire. It should separate from the connector. Repeat for each wire you need to remove.
What Do Different Wire Connector Colors Mean?
The color of a connector might indicate the wire gauge the connector can handle, depending on the number of wires. For example, red twist-on connectors often handle large-gauge wires while blue connectors are often for smaller gauges. However, color varies by manufacturer. Never assume the type or size of wiring based on the connector color. Verify the specifications of your connectors.