Open vs Closed Barrel Crimp Connectors: What’s the Difference?

Crimp connectors are the most common type of connectors used in electrical engineering, and they provide a secure, solder-free way to terminate wires. They come in many shapes, sizes, and materials, but the two main categories are open barrel and closed barrel (or standard barrel) crimp connectors. Both types of wire crimps offer a strong and secure electrical connection, but they have different characteristics and are often used in different scenarios.

What Are Open Barrel Crimp Connectors?

An open barrel wire crimp is usually designed with a U or V shape opening that easily wraps around the wire before being crimped. This design means that the wire isn’t fully enclosed (hence open barrel) and the connector has multiple points of contact with it, ensuring that the wire can withstand high vibrations and mechanical stress.

Key Features:

• Open crimping area (U-shaped or V-shaped) that wraps around the wire.
• Requires a crimping tool with jaws to create the connection.

Main Benefits:

• Stronger mechanical retention – The crimping mechanism offers a strong grip on the wire strands, which reduces the risk of the wire pulling out.
• Better strain relief – They prevent incidents of wires breaking, especially in areas with lots of movement.
• High vibration resistance – They are resistant to vibrations that often weaken grip in other connections.

Where They Are Used

• Automotive wiring – Commonly used in vehicles as the connections can resist vibrations.
• Aerospace and industrial electronics – These need high reliability, so open barrel connectors are preferred.
• Telecommunications and data systems – Great for creating long-lasting connections in these areas.
• HVAC and power distribution – They are used in electrical control panels as these need secure wiring.

What Are Closed Barrel Crimp (Standard Barrel) Connectors?

Closed barrel crimp terminals, or standard barrel connectors, feature a fully enclosed cylindrical barrel where the wire is inserted before being crimped. This design is great for ensuring that there’s secure and uniform compression around the wire, which makes them ideal in areas where reliability is needed.

However, it’s mostly suitable for low-vibration environments as the movements can loosen the connection over time.

Key Features:

• The barrel is fully enclosed, so it completely surrounds the wire.
• It’s compatible with standard crimping tools, making installation easier.
• Available in insulated and non-insulated versions.

Main Benefits

• Easier to use – The enclosed barrel makes it easy to insert and crimp wires.
• Minimises strand separation – Since the compression is uniform, the strands can’t break off.
• Reliable electrical conductivity – The resistance is low and the signal is strong as the connection is uniform.
• Versatile application – Works well in a variety of general-purpose wiring tasks.

Where They Are Used

• Household electrical wiring – Quite common home electrical systems, as they most just need a simple, reliable connection.
• Industrial control panels – Used in switchboards to ensure that power distribution is efficient.
• Low-vibration environments – They are great for environments with little or no vibrations.
• Power distribution systems – Often used in circuit breakers and terminal blocks.

Which One Should I Use?

Choosing between open barrel and closed barrel crimp connectors mostly depends on the specific application, your wiring needs, and the mechanical stress the connection will face.

Choose an open barrel crimp if you need:

• To create a connection that can withstand strain.
• A connection that can withstand vibrations and movements. E.g., in vehicles.
• A more specialised crimp in high-performance electrical systems.

Choose an open barrel crimp if you need:

• To create a simple and reliable connection for general wiring.
• A connector that’s easy to use, especially when you already have a standard crimping tool.
• A connection for low-vibration environments, such as in homes.

Choosing the right type will ensure you create a secure and efficient electrical connection that won’t fail over time.