While wires may be crimped, they should not be heavily tinned with solder prior to installation in a screw terminal, since the soft metal will cold flow, resulting in a loose connection and possible fire hazard. [ citation needed] Screw connectors sometimes come loose if not done up tightly enough at fitting time. Verifying adequate tightening torque requires calibrated installation tools and proper training. In the UK, all screw connectors on fixed mains installations are required to be accessible for servicing, for this reason. [ citation needed] Advantages and disadvantages [ edit ] Two types of screw terminals showing a significant development in design. Basic, with the wires held between the screw heads and the terminals (left) and with the wires held, reversely, between the metal clamping plates and the rear of the terminals (right). USB connectors come in two flavors: host and peripheral. In the USB standard, there is a difference between the two, and the connectors on cables and devices reflect this. However, all USB connectors will have some things in common: a b "Essential Connector Terms and Definitions for Specifiers of Interconnect Wiring Systems" (PDF). Glenair, Inc. 2004 . Retrieved 2019-06-25.

The wire may be wrapped directly under the head of a screw, may be held by a metal plate forced against the wire by a screw, or may be held by what is, in effect, a set screw in the side of a metal tube. The wire may be directly stripped of insulation and inserted under the head of a screw or into the terminal. Otherwise, it may be either inserted first into a ferrule, which is then inserted into the terminal, or else attached to a connecting lug, which is then fixed under the screw head. pitch screw terminals, showing the insertion point of the wire to be connected, the retention screw which holds the wire in place, and the modular connectors on the sides of the individual units allowing multiple pieces to be ganged together. Anything 2.4GHz (Bluetooth, ZigBee, WiFi, and Nordic) generally use the new convention: RP-SMA male on the antennas and RP-SMA female on the modules. It is usually desirable for a connector to be easy to identify visually, rapid to assemble, inexpensive, and require only simple tooling. In some cases an equipment manufacturer might choose a connector specifically because it is not compatible with those from other sources, allowing control of what may be connected. No single connector has all the ideal properties for every application; the proliferation of types is a result of the diverse yet specific requirements of manufacturers. [7] :6 Materials [ edit ]Applications [ edit ] Two paired screw terminals, typically used for connecting ceiling-mounted light fixtures Foreman, Chris, "Sound System Design", Handbook for Sound Engineers, Third Edition, Glen M. Ballou, Ed., Elsevier Inc., 2002, pp.1171–72.

Molex connectors are designed to carry a lot of current: up to 11A per pin. For projects where a lot of power may be needed--a CNC machine, for instance, or a 3D printer- a very common method for powering the project is to use a desktop PC power supply and connecting the various system circuits through Molex connectors. Some screw terminals feature colour coded screws for ease of identification and to aid trouble shooting. Benefits of Screw Terminals a b c Worley, Jon (31 July 2018). "Circular Connector Terminology Guide". NYK Component Solutions . Retrieved 2018-10-15. a b c "Connectors: Failure Mechanisms and Anomalies" (PDF). Naval Sea Systems Command . Retrieved 1 July 2019.The above two connectors were designed to be used together, but there was a problem with this configuration and the FCC started moving towards Part 15 compliance. All this means is that all the SMA RF connectors are changing gender (center pin). Really annoying for those of us who need to mate an antenna to an RF device. The FCC gender change was instituted to prevent home users from damaging RF equipment (think home WiFi) when screwing on an antenna. If all antennas are female, there is no way to damage the center connector. Cellular and GPS (900/1700/1800MHz and 1.57542GHz respectively) generally use the old convention: SMA male for the antennas and SMA female for the modules. Polarity is the final aspect to consider; most often, the sleeve will be considered 0V and the tip will be a positive voltage relative to the sleeve. Many devices will have a small diagram indicating the polarity expected by the device; care should be taken to adhere to this, as an improper power supply may damage the device.

There are many ways of applying a connector to a cable or device. Some of these methods can be accomplished without specialized tools. Other methods, while requiring a special tool, can assemble connectors much faster and more reliably, and make repairs easier. Another familiar connector group are those used for audio-visual applications--RCA and phono. While these can't truly be considered to be of the same family, as the various USB connectors are, we'll consider both of them to be in the same vein. "Phone" Type Connectors Chassis or panel connectors permanently attached to a piece of equipment so users can connect a cable to a stationary device a b Horowitz, Paul; Hill, Winfield (1989). The Art of Electronics (2nded.). Cambridge University Press. ISBN 0-521-37095-7.Mroczkowski, Dr. Robert S. (15 October 2004). "A Perspective on Connector Reliability" (PDF). IEEE. connNtext . Retrieved 1 July 2019. Normalized failure mode distributions were originally compiled from a combination of: MIL-HDBK-978, “NASA Parts Application Handbook”, 1991; MIL-HDBK-338, “Electronic Reliability Design Handbook”, 1994; “Reliability Toolkit: Commercial Practices Edition", Reliability Analysis Center (RAC), 1998; and “Failure Mode, Effects, and Criticality Analysis (FMECA)”, RAC, 1993. Insulation displacement connectors are usually used with small conductors for signal purposes and at low voltage. Power conductors carrying more than a few amperes are more reliably terminated with other means, though "hot tap" press-on connectors find some use in automotive applications for additions to existing wiring. Thousands of configurations of connectors are manufactured for power, data, and audiovisual applications. [3] Electrical connectors can be divided into four basic categories, differentiated by their function: [4]

Mating cycles - Connectors have a finite life, and connecting and disconnecting them is what wears them out. Datasheets usually present that information in terms of mating cycles, and it varies widely from one technology to another. A USB connector may have a lifetime in the thousands or tens of thousands of cycles, while a board-to-board connector designed for use inside of consumer electronics may be limited to tens of cycles. It's important that you select a connector with a suitable life for the application. MountSometimes both ends of a cable are terminated with the same gender of connector, as in many Ethernet patch cables. In other applications the two ends are terminated differently, either with male and female of the same connector (as in an extension cord), or with incompatible connectors, which is sometimes called an adapter cable.