Electrical Connectors Series: An Overview of Common Connector Types
When it comes to cable assemblies, deciding what type of electrical connector to install is the first decision you need to make. The type of connector used ultimately depends on the type of connection needed. Electrical connectors join two electrical circuit paths together. They either connect electronic equipment to one another or they power sources. Depending on the circumstances the connection can be either permanent, semi-permanent, or temporary.
A connector consists of a plug (male connectors) or jacks (female connectors). Adapters are available to connect two different types of connectors together. If you’ve traveled out of the country before you’ve probably had to purchase a power adapter which lets you plug in multiple types of power connectors to a wall socket.
Other important characteristics:
- Pinout
- Physical construction
- Size
- Contact resistance
- Insulation between pins
- Ruggedness
- Vibration resistance
- Water resistance
- Pressure resistance
- Reliability
- Lifetime
- User friendliness
Many kinds of connectors exist with multiple variations. Each has its varying characteristics and specific purpose. In this general overview we’ll cover the most common types which include: D subminiature, USB, RF, and power connectors. In later installments, we’ll take a much more detailed view at a couple of the most popular electrical connectors in the industry.
D-Sub Electrical Connectors
Purpose
The invention of D-Subs allowed for a means of connecting early computer models to monitors, printers, and floppy disc drives. At one point, D-Subs ranked among the smallest connectors used in computer systems. Nowadays, they’re large, cumbersome, and almost obsolete. While they’re no longer prevalent in consumer electronics, they’re still widely used in commercial equipment.
Characteristics
Their D-shaped metal shield provides mechanical support, ensures correct orientation and can possibly screen against electromagnetic interference. Low density d-subs have two rows of pins or sockets while high density d-subs have three. The installation screws make for a semi-permanent, but reliable connection.
Common Applications
You’ll find D-Subs used in RS-232 serial communications, network ports, computer video output, and game controller ports. In addition, they’re widely used in aircraft electrical systems.
Variations
DB9, DB25, DB15, DB37, HD15
USB Electrical Connectors
Purpose
USB connectors came about in the 1990s with the rise of computers and peripheral devices to make connecting these devices easier. It aided in standardizing these connections and eliminated the need for separate power chargers for every individual portable device.
Characteristics
A USB connector is intended as a temporary connection and therefore has flat, durable contacts that can withstand repeated attachment and detachment. Compatible with multiple platforms and operating systems these connectors are an ideal choice for most consumer electronics. Plus, they’re low cost and easy to use.
Common Applications
Most computers and laptops come equipped with several USB ports. Peripheral devices such as smartphones, tablets, printers, keyboards, etc., are connected to computers and power sources via USB ports.
Variations
USB A-type, USB B-type, USB C-type, Micro-USB A, Micro-USB B, Micro-USB AB, USB Mini-b, USB 3.0
Power Electrical Connectors
Purpose
A power connector connects electronic devices or industrial equipment to a power source. They carry either alternating current or direct current. Power connectors make it possible to safely connect and disconnect energized circuits due to their multiple safety features.
Characteristics
Power connectors include a safety ground connection and power conductors. These type of connectors usually have keyed plugs and jacks to prevent users from inserting them into electrical sockets in the wrong orientation. Their construction also contains any arc produced when the energized circuit is disconnected.
Common Applications
Depending on the voltage and environmental protection you’ll find these connectors used in both consumer electronics as well as commercial and industrial equipment.
Variations
NEMA 1, NEMA 5 (typical household outlet), NEMA 14 (used with electric ovens), NEMA L6 (used with welders).
RF/Coax Electrical Connectors
Purpose
Radio frequency connectors, also referred to as coax connectors, work at radio frequencies in the multi-megahertz range. A well designed RF connector blocks external signals from the circuit and prevents any loss of energy. It should also not change the impedance of the transmission line of which it is a part of, otherwise it can result in signal reflection.
Characteristics
These connectors come with a built-in fastening mechanism such as thread, bayonet, braces, or blind mate. This mechanism coupled with springs provides a low ohmic electric contact which results in high mating cycles and reduced insertion force.
Common Applications
You’ll find RF connectors typically used with coaxial cables and in TV receivers, two-way radio, Wi-Fi devices with antennas, and industrial and scientific measuring instruments.
Connectors don’t simply attach two wires together, rather they create a seamless circuit with multiple components. They make it possible to send electrical signals from your keyboard to your computer to your monitor within a fraction of a second. But maybe you don’t want to commit to one circuit just yet. No problem! Connectors also disconnect! You could potentially reroute the electrical circuit as many times as you’d like.
With an endless variety of electrical connectors in the market there’s bound to be one that suits your project needs. If a standard product doesn’t meet your specifications, there are many companies capable of designing and creating custom connectors.
Trimantec’s Electromechanical Group
At Trimantec, we specialize in industrial wire harnesses and connectorized multi-conductor cables. So, whether you need to connect two components or several, our experienced technicians can handle all your cable and harness needs. Send us an RFQ or any questions you may have. We'd love to hear from you!