Connectors solve the problem with the output, extension and branching of the cable route, providing stable and reliable connection between different cables, devices or components. Cable connectors or jacks combine different types of cables and devices and can be differentiated according to their purpose and the type of current that flows through the connected cables. That’s why there is one kind of connectors for DC and another for AC. Connectors also differ according to whether they are designed for connecting power cables or signal cables. Connectors also include luster and neutral terminals as well as PCB terminals. For convenience we can divide connectors into the following types:
- antenna connectors, RF connectors and splitters,
- audio and video connectors,
- auto-connectors and jacks,
- cable terminals, lugs,
- signal connectors (telephone plugs, sockets, connectors for LAN cable, USB connectors),
- industrial and military connectors,
- terminal blocks for electrical boards,
- luster terminals and neutral terminals,
- PCB terminals,
- DC connectors,
- AC connectors.
Antenna connectors and splitters
They are a very common type of connectors, which everyone has at home. They connect the antenna coaxial cable to the TV or branch out the signal through the so called splitter, which is a type of coupler for coaxial cables.
These connectors can be designed for surround or panel mounting. This category includes connectors where there is a twin-lead antenna cable at the input and a female coaxial cable connector at the output (F-035 to RF M connector),
BNC connectors, BNC to SMA, RCA F to BNC M, SMA/m to SMA/f, etc. Connectors are gold plated in order to achieve better signal transmission and to lower the resistance of the transition.
This category includes connectors for speakers,
professional audio connectors XLR Canon,
used for balanced audio connection, mono and stereo connectors JACK 2.5mm,
6 = 3mm for PCB, panel and surround mounting,
which are also called chinch- connectors
C3 connectors – three, four, dice connectors, socket type or with pins for panel and surround mounting, etc.
Cars, of course, have many connectors in their electrical system. Here we will discuss only the jacks which are used to connect audio systems with the electric circuit in the car.
The inconvenience here arises from the fact that each car brand has its own configuration of automotive connectors, therefore car jacks are sold according to the model of the car or the model of its audio system. Other auto-jacks which are used are those connecting the speakers in the audio systems in the cars.
A kind of connector or a jack is also the plug that is inserted into the cigarette lighter socket of the car and the other end serves as a coupler of this socket, or there are jacks for powering mobile phones, laptops, lamps, etc.
Cable terminals and snap-on connectors
Snap-on connectors can have different shape: ear, pin,
torque connector, etc. Furthermore, they have different size and color of the insulation, when insulated. These connectors, also called quick links, are a type of plugs, i.e. when joining the two parts of the connector, normally a special pawl is pressed. After the connection, the pawl is released from the pressure and due to some type of spring or elastic plate there is strong and secure connection between current-carrying parts.
A variation of this type of connectors are those designed for solar panels. They differ from conventional ones by their level of protection which is much higher, due to the extreme conditions in which they have to operate. Cable connectors for solar panels
are waterproof, dustproof, resistant to high temperature and UV resistant. They are also designed to operate from -40 to + 90 ° C because they are installed on the roofs of buildings where the operating conditions are really severe.
They are designed for connecting signal wires and cables for data transmission. This category includes phone sockets and jacks, connectors connecting the phone receiver to the cable, USB connectors, D-sub connectors with a different number of pins, RJ45F
and RG9 connectors, VGA connectors, connectors for ribbon cables, LAN sockets and LAN connectors for building computer networks and many others.
Industrial and military connectors
These are connectors with higher requirements for water protection and mechanical strength. The casing of industrial and military connectors is made of reinforced plastics or metal (usually aluminum) to achieve high durability in adverse and aggressive environments.
This type of connectors meets the IEC-1 standard and provides a secure and reliable connection.
Often military connectors are secured by a screw or a bayonet socket. They resist high nominal and peak currents and have IP44 level of protection and higher.
Terminal blocks for electrical switchboards
These terminals are standardized for DIN rail mounting. They meet the requirements of standard IEC947-7-1. They can be single- and multi-line, colored in gray or light beige when intended for phase conductors or yellow-green when used for neutral earthing.
In this case they are call grounding terminals. They are selected according to the cross section of the cable that will be joined through them and may be from 2 to 10mm2. They usually have various accessories such as terminal caps, indicator marker plates, caps that cover them after connecting, etc.
Luster and neutral terminals
Luster terminals are classic screw terminals for electrical installations. They can be plastic or porcelain. They are produced as line terminals connected in a common unit and are separated by a screwdriver or a knife. They can be designed for DIN rail. Screwless terminal blocks are more and more used lately. There the cable is simply inserted into the terminal which presses it.
Porcelain terminals are used in heating devices, where the temperature would quickly damage the plastic luster terminal. Neutral terminals are bridged because the neutral wire has to be connected to them and there should be no potential difference between the separate neutral wires.
Terminals for PCB
This category includes various terminals for PCB mounting,
connectors for surround and printed assembly,
terminals with compression springs,
wings and couplings. There is an extreme variety of models, technologies, colors and sizes of terminals for PCB mounting and everyone can decide which type of connector he/she prefers.
These connectors are designed to work with DC. This includes all sorts of jacks for adapters and for laptop chargers
as well as power sockets of the types DC-017, DC-036, power supply connectors with screw terminals used to connect a LED tape to a standard power supply without using a solderer, etc. There are also D-sub connectors with different number of pins, etc.
These connectors are designed to operate with mains voltage 220VAC / 50Hz. AC connectors include power connectors for computers and monitors – Standard IEC 60320, male and female, power connectors AC-006A, etc. The proposed classification may appear incomplete as far as there are innumerable types and models of connectors but many of the existing connectors can be assigned to one of the above-mentioned categories. Of course, we need to make it clear that this applies to connectors in the field of electronics and electrical engineering. We are not talking about mechanical or electromagnetic couplings, which have a separate classification and theory.