How Connectors Are Classified and Used in Physics
A Connector is an electro-mechanical device whose job is to connect or disconnect a circuit path. Connectors are made of different materials based on their functions. They come in different shapes, sizes, qualities, and complexities. All the physical attributes of different Connector types are mostly based on their functions. Due to which not all Connectors are the same in terms of mating type, durability, ease of connection, etc. Since most of the Connectors have to work in harsh conditions, their design should incorporate conditions such as high temperature, water, dirt, vibrations, etc.
(Image will be uploaded soon)
The image shows different types of Connectors used to connect electrical circuits.
In today's world, there are a lot of different Connector types that we can use in a lot of various applications. Some Connectors are made for single use whereas some are made for permanent connections. Therefore, there are different types of Connectors available in today's markets, and you need to understand them and use them in your day-to-day life.
Connectors Assembly
Manufactured Connectors have two main parts, which are called housing and terminals. The terminals are the pins that protrude out and are used to transfer electric signals between two components. It is always made up of a material that can conduct electricity. The housing is the outside shell or coating over the terminal pins. Its main job is to hold the terminal pins in place, and also protect it from short-circuiting and from external conditions. It is made up of a material that does not conduct electricity, for example, moulded plastic. It can also be made from insulating materials such as ceramics. We will now look at different types of Connectors.
Types of Connectors and Applications
Every Connector has a male-end called plugs, and a female-end called jacks. There is a vast amount of individual electrical Connector types that can be differentiated in several ways, and now we will see the classification of Connectors based on its applications.
Keyed Connectors: These Connectors can be joined together when they are adequately aligned together. This property helps avoid accidental damage to the terminal pins of the Connectors.
ESD Shielded Connectors: The ESD Connectors have protection from electrostatic discharge, which can damage the circuit of its components.
Locked Connectors: These Connectors have an inbuilt locking mechanism which helps to keep the connection in place.
EMI Filtering: These Connectors have an additional feature that is mounted on the housing. This feature helps the Connector to shield itself from electromagnetic interference.
Water-Resistant Connectors: water can damage Connectors very easily. Hence these Connectors are made water-resistant.
Hermetically Sealed Connectors: These Connectors can be used underwater. It will not get damaged by the water pressure.
Moisture/Oil Resistant Connectors: These Connectors are specifically made to protect them from oil and moisture.
Classification of Connectors Based on Connector Level
Box to Box or Input/Output Connectors: The input/output (I/O) Connectors are for attaching external devices, such as printers, keyboards, and displays, to the server.
Wire to Board Connectors: These types of Connectors are used to connect wires to a printed circuit board to enable connectivity between circuits.
Chip to Package Connectors: A chip to package Connector comprises a conductive member electrically coupled to the contacts and the remote device; wherein the contacts are arranged to be electrically and mechanically coupled to a circuit board.
Board to Board Connectors: This type of device is engineered to provide signal connections between two printed circuit boards (PCBs).
Classification of Connectors Based on Connector Function
Terminal Block: These Connectors terminate a single wire and connect it to a circuit. We use terminal block Connectors to connect wires from the same circuit without cutting the wires. Terminal block connection is further categorized as-
Barrier Strips- These are the interConnectors that contain metal strips, and screws or Connectors for easy connection and termination of wires.
Printed Circuit Board Terminal Blocks (PCB)- They are directly embedded into the circuit board and are commonly used for power, data, and signal connections across industries.
Multiple Terminal Connectors (MTC)- These blocks are used to connect multiple wires to a single terminal block, thereby reducing the reliability issues faced when multiple wires are connected in a single clamp.
Pluggable Terminal Blocks- They have a cable opening to allow the connection of cables along with a plug output that allows easy connection to a socket. They are useful in hot swapping situations.
Binding Post: The binding post Connectors are widely used in test fixtures for wire termination. You can find them in loudspeakers and audio amplifiers.
Blade: This Connector uses conductive blades that are flat and connect single wires to the blade receptacles. These are attached to the connecting wires and are generally used in speakers and thermostats.
Ring and Spade: In this, the connection is embedded between a threaded post and a screw. It allows making easy connections that can be removed effortlessly as the lock is partially closed.
Plug and Socket: They are suitable for use in control circuits. They provide connections between control circuitry and components. Plug and Socket Connectors are used in appliances to handle video and audio such as USB, network computing, HDMI, etc.
Rack and Panel: These Connectors are specially designed to connect any device to an equipment rack. They are designed for military and commercial performance and are manufactured to the highest quality and durability standards. This connects electronic pieces that can be removed with stationary or immovable parts of equipment. It is further classified into three- rack and panel, cable to cable, and cable to panel. They are used home theatre systems, printers, modems, etc.
Classification of Connectors based on Connector Level Termination
Insulation Displacement Connectors (IDC)- These Connectors attach insulated wires and do not use any pre-stripping of insulation. A group of blades cut the insulation when electric insulators are inserted. This helps to decrease the current handling potential.
Crimping- These make a connection between the wires and the Connectors which can be separated easily after use. These are easy to use, safe, and cost-effective Connectors.
Terminologies Related To Connectors
Some terms are used to describe the Connectors. These terminologies are mentioned below:
Gender- The gender of the Connector is male or female. It means whether the Connector will plug in or is plugged into. Sometimes the conductivity determines the gender of the Connector.
Polarity- The property of a Connector that allows it to be connected in one orientation is known as polarity. The materials which prevent Connectors from being connected wrong are said to be keyed or polarised.
Contact- The business portion of the Connector is known as the contact. These are generally the metal parts that form an electrical connection. This is the place where the problem occurs. They can become oxidized and soiled and may fade with time.
Pitch- The contacts in a Connector are arranged in repeated patterns. Pitch is defined as the distance from the center of one contact to the center of the next.
Mating Cycles- The information about the finite life of the Connectors is expressed using the term mating cycle. The finite life can be worn out if the Connectors are connected and disconnected continuously. For example, the lifetime of a USB is thousands or ten thousand cycles.
Mount- The term mount can be described as how the Connector is mounted when in use, the angle of the Connector related to its attachment or how the Connector is mechanically attached.
Strain Relief- The electrical connections are somewhat weak when the Connectors are mounted on a cable or board. Strain relief is provided to transfer forces acting on the Connector to an object which has more mechanically sound than weak electrical connections.
Application of Connectors
As we have seen, there are a lot of Connector types. Because there are so many different types of Connectors, they tend to have unique roles. We will now see some unique applications of Connectors.
You can find Connectors on every computer and laptop.
We are all aware of the Universal Serial Bus, also known as USB, which is also a standard Connector.
Connectors are also used as radio frequency Connectors. These Connectors help prevent the change of the transmission line’s impedance.
The Connectors named eight positions/ eight conductors (8P8C) are used in ethernet cables and CAT5. They look like RJ45 cables but the socket of 8P8C is different from RJ45.
D-Subminiature is the Connectors used in modem ports and IBM-compatible computers. There are different types of D-subminiature Connectors. These are thermocouple contact options, PCB and crimp mounts, solid machined contacts, etc.
The DC Connectors and AC power sockets/ plugs are installed to prevent people from getting shocked when they come in contact with energized conductors.
FAQs on Types of Connectors in Physics: A Complete Guide
1. What are the fundamental components of an electrical connector?
Every electrical connector is fundamentally composed of two main parts: the housing and the terminals. The terminals are the conductive metal pins or contacts that establish the electrical connection for signals and power to flow. The housing is the protective, non-conductive shell, often made of moulded plastic or ceramic, which holds the terminals securely, guides their alignment, and insulates them to prevent short circuits.
2. How are electrical connectors broadly classified based on their application?
Electrical connectors can be classified in several ways, but a common method is by their application and the components they connect. The main categories include:
- Wire-to-Board Connectors: These link wires to a printed circuit board (PCB).
- Board-to-Board Connectors: These are designed to connect two separate PCBs together.
- Wire-to-Wire Connectors: These join two individual wires or two cable assemblies.
- Box-to-Box (I/O) Connectors: Used for external connections, such as connecting a printer or keyboard to a computer.
3. What are the most important specifications to consider when selecting a connector for a project?
When choosing a connector, several key specifications are crucial for ensuring safety and functionality:
- Voltage Rating: The maximum voltage the connector can handle before its insulation fails.
- Current Rating: The maximum electrical current that can safely pass through the terminals without overheating.
- Number of Pins: The required number of individual circuits the connector must support.
- Mating Cycles: The number of times the connector can be connected and disconnected before it wears out.
- Physical Size and Mount Type: Ensuring the connector physically fits the design and can be mounted correctly (e.g., on a panel or PCB).
4. What materials are typically used to manufacture electrical connectors and why?
Connectors use a combination of conductive and insulating materials. The terminals are usually made from copper alloys due to their excellent conductivity and malleability. These are often plated with inert metals like gold, tin, or nickel to resist oxidation and ensure a reliable connection. The housing and other insulating parts are typically made from durable plastics or ceramics, chosen for their high electrical resistance and mechanical strength.
5. What are some common examples of connectors found in computers and home electronics?
You can find many types of connectors in everyday electronic devices. Common examples include:
- USB (Universal Serial Bus): Used for data transfer and power for peripherals like keyboards, mice, and external drives.
- HDMI (High-Definition Multimedia Interface): Transmits high-quality audio and video signals, commonly found on TVs and monitors.
- 8P8C (often called RJ45): Used for ethernet network cables to connect devices to a network.
- DC Power Connectors: Barrel-shaped connectors used to supply DC power to laptops and other small devices.
- Audio Jacks (3.5mm): Used for headphones, microphones, and speakers.
6. What is the functional difference between a connector's 'gender' and its 'polarity'?
While both relate to how connectors mate, gender and polarity serve different purposes. Gender refers to the physical form: the 'male' part (plug) has pins that protrude, while the 'female' part (jack or socket) has receptacles to accept those pins. Polarity is an alignment feature, often a specific shape or key, that ensures the connector can only be inserted in one correct orientation. This prevents accidental reversal of power or data signals, which could damage the device.
7. Why is strain relief considered a critical feature for cable connectors?
Strain relief is a feature that protects the weak electrical connections where wires are soldered or crimped to the connector's terminals. When a cable is pulled or bent, the force is transferred to the strain relief component—a more mechanically robust part of the connector's housing—instead of directly onto the fragile electrical joints. This significantly improves the durability and lifespan of the cable and prevents connection failures.
8. How do 'keyed' connectors prevent incorrect connections?
A keyed connector is designed with an asymmetrical shape, such as a notch, a D-shape, or an off-centre pin, that physically prevents it from being plugged in incorrectly. It acts as a mechanical guide, ensuring that the plug and socket can only align and mate in the single, correct orientation. This is a simple but highly effective way to protect circuits from damage caused by mismatched pin connections.
9. How do water-resistant connectors differ from hermetically sealed ones in terms of protection?
The level of protection differs significantly. A water-resistant connector is designed to protect against splashes, rain, or moisture and often uses gaskets or seals to prevent water ingress under normal atmospheric pressure. A hermetically sealed connector provides a much higher level of protection; it is completely airtight and can be fully submerged in water, resisting pressure at certain depths without leaking. This makes them suitable for underwater or extreme environmental applications.
