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What Are The Types Of Wire Harness Connectors And Terminals

by | May 26, 2023

Wire harness connectors and terminals are crucial components that enable the connection and termination of wires in a wire harness. Violin Technologies, a renowned leader in India’s best wire harness manufacturers, specializes in producing high-quality wire harnesses for industries like automotive, aerospace, and electronics. With expertise in design, manufacturing, and logistics, they seamlessly integrate these components to deliver exceptional customer outcomes.

Wire Harness Connectors And Terminals

Wiring harness connectors and terminals are crucial in joining the ends of wires or cable assembly within a harness. They facilitate secure and reliable connections between wire assemblies and electrical components like switches, sensors, connectors, or electrical circuit boards. These connectors come in various sizes, the wire-to-wire and the board-to-wire configuration, to cater to different applications, environmental conditions, and connection requirements.

Wire harness manufacturers prioritize thorough testing of the final product during the manufacturing process to ensure compliance with safety standards, assess functionality, and guarantee overall quality.

Conversely, wire harness terminals are specific components within a humble wire harness connector that interface with the wire ends. They are designed to hold the wire and establish electrical conductivity securely. Terminals can be metal pins, blades, sockets, or lugs integrated into the connector body. The weather-resistant connectors and termination methods determine the appropriate connection type, like crimp barrels, insulation displacement slots, solder cups, or screw terminals.

Wire harnesses provide protection against extreme temperatures, dirt, contaminants, dust, constant vibration, and moisture. They are classified as male and female, with plugs typically serving as male connectors and jacks as female wire harness connectors.

Backshells are commonly used with circular connectors in industrial and high-reliability applications to protect from environmental factors, mechanical stress, and electromagnetic interference. Military and aerospace backshells adhere to regulations like SAE AS85049 in the USA.

Types Of Wire Harness Terminals

1. Crimp Terminals: Crimp terminals are the most widely used single or multiple wire harness terminals. They consist of a metal barrel or sleeve that is crimped onto the stripped end of a wire. Crimp terminals come in various designs, such as butt connectors, ring terminals, spade terminals, hook terminals, bullet terminals, and pin terminals. They provide a secure mechanical and electrical system by compressing the metal barrel around the wire, ensuring good conductivity and preventing wire pullout.

2. Insulated terminals: Insulated terminals have plastic or rubber insulation covering the metal barrel or sleeve. The insulation provides electrical insulation and protection against moisture, dust, and vibration. Insulated terminals are commonly used in automotive and industrial applications where environmental factors are a concern.

3. Heat-shrink terminals: Heat-shrink terminals are similar to crimp terminals but feature a heat-shrinkable insulation sleeve. When heated, the insulation sleeve shrinks and conforms tightly around the wire and terminal, providing excellent insulation and protection. Heat-shrink terminals are often used in applications requiring a waterproof or sealed connection.

4. Solder terminals:  Solder terminals have a metal barrel or lug soldered to the wire. The solder forms a strong and permanent connection, ensuring electrical conductivity and mechanical strength. Solder terminals are commonly used in applications where a high level of reliability is required.

5. IDC (Insulation Displacement Connector) butt terminals: IDC butt terminals allow for quick and easy connection of wires without stripping or crimping. They feature sharp metal contacts or blades that penetrate the insulation of the wire when pressed, making a connection with the conductor inside. IDC terminals are commonly used in modern technology like telecommunications, data communications, and computer applications.

6. Screw terminals: Screw terminals have a metal terminal block with a screw that clamps down on the wire, creating a secure connection. Screw terminals are often used in applications that require frequent connection and disconnection, as they offer easy and reliable wire termination.

7. Push-on terminals:  Push-on wire harness terminals, also known as quick-disconnect terminals, feature female connectors with tabs or blades that provide a secure connection when pushed onto a corresponding male terminal. They are widely used in automotive and appliance applications.

It’s important to select the appropriate types of wire harness fork terminals based on factors such as wire gauge, current carrying capacity, environmental conditions, and the specific connection requirements of the application. Proper installation techniques, including crimping or soldering, should be followed to ensure reliable and durable connections within the wire harness.

Types of wire harness connectors

Types Of Wire Harness Connectors

1. Blade connectors

The blade connector is one of the most common wire harness connector pins. This connector features flat metal blades or tabs that insert into a corresponding female connector, establishing an electrical connection. Blade connectors are widely used in automotive applications due to their simplicity and ease of installation. They can handle high currents and are available in different sizes to accommodate various wire gauges.

2. Pin connectors

Pin connectors consist of a cylindrical metal pin that fits into a corresponding socket or female connector. These connectors are prevalent in computer and electromechanical devices due to their compact size and reliable connection. A connector pin offers better vibration resistance than blade connectors, making them suitable for mobile and high-shock environments. They are available in various configurations, such as single-pin, multi-pin, and dual inline pin connectors (DIP).

3. Circular connectors

Circular connectors feature a round housing and are widely used in aerospace, military, and industrial equipment industries. They provide multiple pins or sockets arranged in a circular pattern within the housing. Circular connectors are known for their robustness, resistance to environmental factors such as moisture, dust, and vibrations, and high reliability.

They often use threaded coupling mechanisms or bayonet-style locks to secure the connection. These electrical connectors can handle high currents and accommodate various wire sizes.

4. Rectangular connectors

As the name suggests, rectangular wire harness connectors and terminals have rectangular housing and are widely used in industrial and commercial applications. They are versatile and suitable for applications that require multiple wire connections. Board-to-board connectors feature multiple pins or sockets arranged in rows or grids within the housing. They are known for their high contact density, allowing numerous connections within a compact space.

These wire connectors can handle moderate to high currents and are available in various sizes, pin counts, and configurations. Rectangular harness connectors often use locking mechanisms like latches or screws to ensure a secure connection. They are commonly employed in automation, control systems, transmit signals, and electronic signal contacts.

5. Terminal blocks

Terminal blocks are modular connector pins that allow multiple wires to be connected or terminated. They contain an insulating body with metal terminals or screws that secure the wires. Terminal blocks simplify wiring by providing a convenient way to connect and disconnect wires without soldering.

They are commonly used in industrial and electrical distribution applications, where numerous connections must be made. They provide a reliable and secure connection, and their insulation properties ensure electrical safety.


Violin Technologies, a top contract manufacturer, supplies custom wire harness connectors and terminals. Our skilled wiring cable engineers utilize carefully select connectors based on connection types, insulation needs, and power contacts, electronic signal contacts. Connect with us, and we will provide you with our latest products in wire harness connectors and terminals to suit your requirements.

Rasmita Patro | author

Rasmita Patro

About the Author

Meet Rasmita Patro, a content writer, a former teacher, and a former HR with a passion for storytelling, creating compelling content that engages and informs readers. She has a Master’s in Economics and an MBA degree in Human Resources. Her expertise spans a variety of industries, including finance, healthcare, technology, and others. She has a particular inclination toward crafting blog posts, articles, and social media content that resonates with the target audience. She loves reading different genres of books, love to experiment with cooking, and listening to soothing music.