What’s An Electrical Connector? Complete Guide 2022

Electrical Connector

Connectors are components or tools used to connect or disconnect circuits electrically, among other things. There are a ton of electrical wire connectors, too many to elaborate on in a single guide, however, there are a couple of connectors that as a maker you will come across.

What’s an electrical connector? To connect electrical terminations and build an electrical circuit, electro-mechanical devices called electrical connectors are used. Typically, connector housings are made of plastic that has been molded. Typically, metal or other conductive materials are used to make terminals.

Although there are many different types of connectors, the vast majority are either one-piece types that are used alone or two-piece types that include a plug and socket. If electrical connectors interest you, continue reading.

What’s An Electrical Connector?

Any structure that permits the flow of electricity is considered to be an electrical connection. Although it isn’t explicitly stated in the definition, a connection permits the transmission of electricity with a specific intention, not just any transmission. Every electrical device has connections to other electrical devices, but the majority of them have a single overarching design. The transfer of power is made possible by the interlocking of a cable’s specialized ends with the ends of other cables that are compatible with it.

A mind-boggling variety of systems, from plugging in a toaster to powering a microchip, are included in the term “electrical connection.” Every object that uses electricity has a connection that extends from the outside. There are connections inside the device that go to various parts of the system. All the way back to the source of the electricity are a number of electrical transformers and substations outside the device. It wouldn’t be surprising if even a basic device required hundreds of electrical connections in order to function.

Features Of Electronic Connectors

Electronic connectors of some types have characteristics that make them suitable for particular applications. These are a few of the types:

  • Hermetically Sealed Connectors use highly engineered glass-to-metal sealing to create an airtight sealing. Extreme environments won’t harm them because they are resistant to air and moisture. They can withstand pressures up to a certain depth and function safely when submerged in water.
  • Water-Resistant Connectors protect electronic connections from damage caused by exposure to water. They are not made to work underwater, in contrast to hermetically sealed connectors.
  • Moisture and Oil Resistant Connectors protect the electronic connections from damage caused by exposure to moisture and oil.
  • EMI and/or RFI Filtering on connectors provides protection to electronic connectors from electromagnetic interference (EMI (electromagnetic interference) and/or RFI are two examples.
  • ESD Shielded Connectors protect the electronic connections from electrostatic discharge (ESD) damage.
Electrical Connector

Types Of Electronic Connectors

The following is not an exhaustive list of electronic connectors:

Board-to-board Connectors

The term “board-to-board connectors” refers to a collection of connectors that connect two printed circuit boards (PCBs) together without the use of a cable. These PCB-based connectors are constructed from a male and a female member using either surface mount or through-hole technology. PCBs may be connected parallelly or perpendicularly. A mezzanine connector connects the edges of single-sided or double-sided PCBs are mated by an edge connector while the PCBs are stacked.

IEC Connectors

A group of connectors known as IEC connectors adhere to IEC standards. The IEC 60320 standard defines the parts for attaching power supply cords to electrical apparatus with a 250 V voltage rating and a 16 A current rating. The current rating, temperature rating, dimensions, and a number of terminals of the various standardized IEC connector types vary.

Each IEC component is identified by the prefix “C” followed by a number. IEC connector components are sold in pairs and consist of a connector (male component) and an inlet (female component). IEC connector parts include, for instance, the C13 connector and C14 inlet, which have three conductors, a 10 A current rating, and a maximum temperature rating of 700C.

Backplane Connectors

A backplane is used as a backbone structure to connect several PCBs in which the pins of one PCB are connected to the same relative pins of another PCB. It is frequently used in computers and telecommunications equipment to enable data transfer between its parts.

Power Connectors

Power connectors are connectors that permit the flow of electrical current to power a device. Direct current (DC) or alternating current (AC) are both carried by them. The following are examples of the various types of power connectors:

Barrel Connectors

Electronic devices are connected to an external power source by barrel connectors, also referred to as coaxial power connectors. Through the barrel connector, low voltage DC is delivered to the electronic device from a wall-mounted adaptor. These connectors, which come in standard diameters and lengths, are widely used in consumer electronics.

The barrel plug is made up of insulators that divide concentric metal sleeves. Barrell jack pins are taken up by the inner sleeve. The barrel jack can be mounted on a PCB, a panel, or a cable. The plug’s inner sleeve touches the pin when the plug’s outer sleeve is pushed by a cantilevered spring that is installed inside the jack.

Box Header Connectors

The type of header used to identify board-to-board connectors. In box headers, the terminals are surrounded by their header. Meanwhile, in pin headers, the terminals are exposed.

Molex Connectors

Molex connectors were created and patented by the Molex Connector company in the late 1950s. To power computer drives and devices, these connectors are frequently used. They are made up of pins made of cylindrical spring metal that slide into sockets made of the same material. A Molex connector typically has 2-24 contacts that are arranged in single or double rows and keyed to ensure proper plugging orientation. Plastic housing holds the pins and sockets in place.

Nema Connectors

The National Electrical Manufacturers Association (NEMA) has established a standard for a group of power plugs and outlets known as NEMA connectors. In North America, NEMA standards are widely used, and some nations have adopted them.

A distinctive coding scheme identifies the features of the NEMA connectors’ parts. The locking mechanism is mentioned in the first identifier. Twist-locking NEMA components have first identifiers that begin with the letter “L,” while non-locking NEMA components have first identifiers that are blank. A second identifier is a number that comes before the hyphen and denotes the NEMA type. The number of poles (current-carrying terminals), the number of wires connected, the voltage rating, and other details are all indicated by the NEMA type. A number that follows the hyphen and represents the third identifier is the current rating in amperes. The final indicator is a letter designation, which is as follows: “Plugs are designated by the letter “P,” and outlets are designated by the letter “R.”

NEMA connectors can be twist-locking or non-locking, as was already mentioned. Non-locking NEMA connectors use straight blades in their plugs which can be easily connected or disconnected to their corresponding receptacles. Twist-locking NEMA connectors use curved blades in their plugs that can be rotated and latched into place, protecting the connector from accidental disconnection. The best connectors for commercial and industrial equipment are NEMA twist-locking connectors.

Terminal Block

When connecting or terminating two or more wires, a terminal block is a modular, insulated block. It joins a number of terminals that are set up in a long strip. A clamping system secures the terminal wires into the conductive metal strip, which is located inside a terminal block and allows electrical conduction between the joined terminals. The wire orientation options include vertical, horizontal, and 450-degree inclines. A panel or DIN rail can support mounting terminal blocks.

Uses For Electrical Connectors

Electrical connectors play a specific role in the wide variety of end products. The electrical connectors that are most frequently used are illustrated in the examples below.

  • 8P8C—These modular electrical connectors, which go by the abbreviation “eight positions/eight conductors,” have eight positions, all of which have conductors. Despite their many applications, CAT5 and Ethernet cables are where these connectors are most frequently seen. Although the socket that the connector’s end fits into is different, these connectors resemble RJ45 cables used for Landline telephones.
  • D-Subminiature—Computers that are IBM compatible and some modem ports have these electrical connectors. D-subminiature electrical connectors come in different varieties, some with solid machined contacts, crimp and PCB mounts, thermocouple contact options, and so forth, despite being used primarily for testing, computers, and telecommunications.
  • USB—This connector, which stands for Universal Serial Bus, is the industry standard for bridging devices. These electrical connectors come in various types and have various functions, despite being frequently used in the production of Mac, Apple, and PCs.
  • Power—There are several different types of this type of connector, which is also known as AC power plugs/sockets and DC connectors. These include NEMA connectors as well as industrial and multiphase power plugs and sockets. These electrical connectors’ main objective is to shield users from electric shocks in the event that they unintentionally make contact with energized conductors. Safety ground connections and power conductors are included with power connectors.
  • Radio Frequency—The radio frequency (RF) connector is yet another popular electrical connector application. These connectors must not alter the transmission line’s impedance in order to be used at radio frequencies.

Terminologies Used In Electronic Connectors

The following terms are used to describe the characteristics and requirements of electronic connectors:

Electronic Connector Gender

Electronic connectors are typically found in pairs, with a gender designation on each half. The male component is called the plug, while the female component is called the jack or socket. The terminals of the jack are housed in recessed holes (known as “socket holes”) that are connected to a wire, cable, or another device. To make a connection, the plug’s terminals must be inserted into the jack’s slots.


The majority of connectors only allow for one orientation of insertion due to the polarity of electric charges. Electronic connectors have keying, which prevents the improper orientation of the mating surfaces. A keyway protects the pins from mechanical and electrical damage caused by risky and incompatible connections. It also prevents putting the connector in the incorrect socket or at the incorrect angle. A keyway makes symmetrical connectors easier to handle.

Pin Sequence

Specific pin connections must be made in a certain order when using some electronic connectors. Before inserting another set of pins, a particular set must first be plugged in.

Mating Cycles

The number of times an electronic connector can connect and disconnect from its counterpart while still adhering to all of its specifications is referred to as a mating cycle. Every type of connector has a different limit; a USB connector can be mated thousands of times, whereas FFC and FPC connectors only have a limited number of mating cycles. The type of connector material, the type and thickness of the plating, the resistance pass/fail threshold, and the mating style are all factors that affect the mating cycle.

Locking Mechanisms

During mating, a locking mechanism secures the connector in place. It stops the connector from moving when it is jostled or bumped. Doing so, it prevents the connector from accidentally coming undone while the device is in use, which could cause damage. Electronic connectors can be locked in several different ways, such as with push-pull connectors, bayonet couplings, and fine thread screw couplings.

Number Of Contacts

When we talk about contacts, we’re talking about how many conductive materials there are that connect electrically.

Contact Pitch

Pitch, also known as contact pitch, is the center-to-center distance between two adjacent pins, which is typically expressed in millimeters. There may be a difference in the pitch between rows and columns when pins are arranged in an array. The compatibility of connectors is impacted by contact pitch.

As there are fewer terminals per connector area, the likelihood of electrical arcing is reduced. A larger pitch. When the current jumps from one pin to the next, especially if the pins are too close to one another, electrical arcing occurs.

Pin Numbering

An electrical connector’s pins are all serialized. According to a standardized sequence, a number is given to a particular pin. The pins are assigned numbers in integrated circuits counterclockwise.


The term “mount” describes the positioning or mounting of an electronic connector on an electrical device. Board mount (through-hole mount, surface mount, edge mount), panel mount, and cable mount are the different mounting styles.


How the terminals are connected is referred to as termination. The subsequent chapters will go into more detail about the termination methods.

Performance Parameters

Performance parameters describe the circumstances under which an electronic connector is intended to function securely. These specifications include the minimum and maximum operating temperatures, the current rating, the voltage rating, and the temperature rating.

Strain Relief

The term “strain relief” refers to a fitting or bushing that dissipates forces acting on an electronic connector in order to keep it mechanically stable and prevent stress and damage.


Connectors for electronic circuits are known as electronic devices. These tools are used to assemble, install, and power electrical devices.

The terminals and the housing make up the two main parts of an electronic connector.

Board-to-board, power, terminal block, USB, and audio/video connectors are among the types of electronic connectors covered in this article.

Also Read: What Is A USB 4?