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Glossary

Definitions for jargon, scientific terms and phrases used at Harwin and across the connector and electronics industries.

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M20

A 2.54mm pitch (0.1") PCB connector system from Harwin based on simple pin header and socket styles. Part numbers all start with M20. The connectors are available in Board-to-Board or Cable-To-Board styles, and are generally suited for static equipment and consumer electronics.

M22

A 2.00mm pitch (0.079") PCB connector system from Harwin based on simple pin header and socket styles. Part numbers all start with M22. The connectors are available in Board-to-Board or Cable-To-Board styles, and are generally suited for static equipment and consumer electronics.

M300

A 3.00mm pitch high-reliability connector range designed and manufactured by Harwin. This selection of power connectors will handle up to 10A per contact, and is available in 3-contact (single row), 6 or 10-contact (double row). Jackscrews are located at either end of the connector housings. Available in Board-to-Board, Cable-to-Board and Cable-to-Cable configurations.

Make-Before-Break

On an electrical switch or relay, on mating the new connection is engaged before the previous connection is broken, so the center contact is momentarily connected to both contacts. This can also be referred to as "First-To-Make" or "First Mate Last Break (FMLB)".

Mate-Before-Lock

A style of Jackscrew or Screw-Lok that enables the connectors to be mated before the screws need to be engaged. Easier to use that jackscrews that "jack" together connectors, as you can fully screw down one side before starting on the other side. See the Mate-Before-Lock blog article for more information.

Mating

The act of plugging together two connectors so that current can flow across the connection. Sometimes called coupling. The reverse action of separation can be called unmating, de-mating, uncoupling or other variants of these. See also Mating Cycles.

Mating Cycles

The minimum number of times that a connector pair can be mated and unmated, and that their electrical and mechanical performance will still be maintained. Mating cycles will be defined for connectors, because continued mating and unmating will have various physical effects that will eventually affect performance. These include wear on the mating surface and permanent set on the spring contacts.

Mating Height

Used specifically for Board-to-Board connectors that connect in a parallel or mezzanine configuration (the two boards are parallel to each other, one above the other). Both connectors are vertical connectors (the mating face is vertically above the tails/leads). The mating height is the distance between the two PCBs, specifically between the two surfaces of the PCBs that face each other.

Mechanical Fixing

A separate part of a connector that does not carry current, but is purely to give a robust connection to either the PCB or the mating connector (or both). These fixings will give additional strength in addition to solder joints or the holding force of the mated connectors, which is important or even crucial in a connection subject to mechanical stress.

Mechanical Stress

Any action that causes physical wear or strain on a device or connection. This can include mating actions, vibration and shock, friction against other system elements, or induced stresses as an item warms or cools.

Metal Backshells

A type of backshell that is manufactured from metal in order to also give shielding to the connector. Depending on the design, the cable exit may also be designed to accept an external metal braid being connected, by means of a tie-band or similar. This would then give a completely shielded cable assembly when fully assembled.

Minimum Line Value

The minimum sales value of a specific product that a manufacturer will accept on one order. Also referred to by the acronym MLV. This is to ensure that manufacturers are keeping to sound economic rules and not spending more on shipping than on the potential profit of an order.

Minimum Order Quantity

The minimum amount of a specific product that a manufacturer will accept on one order. Also referred to by the acronym MOQ. A company will set an MOQ on non-stocked items to ensure that any order placed for these items makes economic sense to manufacture.

Mis-mating

The failed attempt at mating two connector halves. In the best case, it means the user must simply try again. However, depending on the connector design, it may also be possible to temporarily or permanently damage the connector - which in the worst case would mean the two halves can no longer be engaged together.

Misalignment

A particular form of mis-mating, where the connectors are mostly lined up, but a bit out in one direction. Certain connectors will have systems that accommodate a certain amount of misalignment, such as large chamfers on the mating faces, alignment posts, or spring loaded contacts that mate with a flat surface.

Mixed Technology

Any single circuit item that incorporates more than one function or connection technology. In connectors, can either refer to a mixture of Throughboard and SMT tails/legs/leads, or a mixture of contact types (such as signal and power contacts) in one connector.

Modular

A type of design of equipment or device that allows for easy replacement of certain parts of the device by making the whole piece of equipment from smaller sub-units. For the equipment to be truly modular, it should be a simple operation to replace any sub-unit within the equipment.