Connectors plastics used

Optical connectors ate used to terminate and interconnect fiber optic cables (see Fiber OPTICS). Transmission of information by light through optical fibers made of glass or plastic is less expensive in many cases than transmission of electric signals through wire. An advantage of fiber optic technology is that it is... 

Once the elaboration of the sensor is performed, the wires are brazed on a plastic connector often used in electronics (see Figure 9.11). 

The Swiss company, WW Fischer, offers PTFE (Teflon PTFE or Hostaflon), PBT (Celanex, Crastin, Ultradur or Valox) or PEEK (Victrex) insulator material options in its 405 series of cylindrical connectors according to the requirements of working temperature and other criteria. PEEK is an expensive polymer which tends to be employed when other materials fail to meet the specification requirements of the application. Other Fischer connector types use polyamide-imide (Torlon) or POM (Celcon, Delrin or Hostaform). Elastomeric seals used by Fischer in conjunction with their connectors are made from acrylonitrile-butadiene rubber (NBR N BUNA) or to MIL-P-25732, fluoroelastomer (FPM VITON), polychloroprene elastomer (CR Neoprene), ethylene-propylene diene elastomer (EPDM) and styrene-ethylene-butadiene-styrene thermoplastic elastomer (TPE-S or TPE-O) where each compound is followed by its trade name. Fischer s Swiss competitor, Lemo, manufactures a similar range of connectors including the Redel types which have a plastic body. 

Insulators. Molded plastics serve as insulators for multicontact connectors and glass is used in hermetic connectors intended for bulkhead... 

Silver is often preferred as an undercoat for rhodium by reason of its high electrical conductivity. A further advantage of silver in the case of the thicker rhodium deposits (0-0025 mm) applied to electrical contacts for wear resistance is that the use of a relatively soft undercoat permits some stress relief of the rhodium deposit by plastic deformation of the under-layer, and hence reduces the tendency to cracking , with a corresponding improvement in protective value. Nickel, on the other hand, may be employed to provide a measure of mechanical support, and hence enhanced wear resistance, for a thin rhodium deposit. A nickel undercoating is so used on copper printed connectors, where the thickness of rhodium that may be applied from conventional electrolytes is limited by the tendency of the plating solution to attack the copper/laminate adhesive, and by the lifting effect of internal stress in the rhodium deposit. 

The second major area for the use of plastics in electrical applications is at the terminations of the conductors. The connectors that are used to tie the wires into the equipment using the power, or used to connect the wires to the power source, are rigid members with spaced contacts. These are designed to connect with a mating unit and to the extension wires. The other type of wire termination is terminal boards where there are means to secure the ends of the wire leading to the equipment and the internal wiring in the equipment. These termination units require ... 

If the connectors are to be used in high frequency applications, they must be made of plastics with low dielectric loss to avoid either damage to the part or signal loss in the circuit. 

When using molded plastics parts such as the connectors and the circuit supports, it is important to make sure that the moldings, in addition to being made to close tolerances, be made under molding conditions that make for stable products. Electrical products are subjected to strong electrical fields in addition to the usual environmental abuse. Distortion of the product can lead to serious electrical malfunction by changing spacings that will alter electrical characteristics and if... 

Molecular modeling helps students understand physical and chemical properties by providing a way to visualize the three-dimensional arrangement of atoms. This model set uses polyhedra to represent atoms, and plastic connectors to represent bonds (scaled to correct bond length). Plastic plates representing orbital lobes are included for indicating lone pairs of electrons, radicals, and multiple bonds—a feature unique to this set. 

Flame-retarded grades are widely used for various computer connectors and circuit board components. Representative applications are edge card connectors, grid arrays and memory modules. Non-flame-retarded grades find use in automotive under-the-hood applications, typically connectors and related parts. As higher temperature soldering techniques become more common in the automotive industry, the use of high-temperature plastics such as PCT is expected to increase. It is also possible to formulate unreinforced PCT with crystallization aids and... 

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