Reed Relays and
Electronics India Limited
Manufacturer of Reed Switches, Reed Sensors and Reed-based products
Reed Relays and Electronics India Limited Incorporated in 1971
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Contact

Contact is the current-carrying parts of a reed contact that engage or disengage to close or open electrical circuits. This area is plated or sputtered with Ruthenium, Rhodium, Tungsten or other material.

Merriam-Webster Online Dictionary
contact (noun)
1.
a) union or junction of surfaces
b) the apparent touching or mutual tangency of the limbs of two celestial bodies or of the disk of one body with the shadow of another during an eclipse, transit, or occultation
c) (1) the junction of two electrical conductors through which a current passes
(2) a special part made for such a junction
2.
a) - association relationship
b) - connection communication
c) an establishing of communication with someone or an observing or receiving of a significant signal from a person or object - radar contact with Mars
3.
a person serving as a go-between, messenger, connection, or source of special information - business contacts
4.
- contact lens
contact (verb)
intransitive verb
transitive verb
to make contact
1.
to bring into contact
2.
a) to enter or be in contact with - join
b) to get in communication with - contact your local dealer
contact (adjective)
maintaining, involving, or activated or caused by contact - contact poisons contact sports contact dermatitis
Electrical_contacts (Wikipedia)
Schematic for an electromechanical relay showing a coil, four pair of normally open and one pair of normally closed contacts

An electrical contact is an electrical circuit component found in electrical switches, relays, connectors and circuit breakers. Each contact is a piece of electrically conductive material, usually metal. When a pair of contacts touch, they can pass an electrical current with a certain contact resistance, dependent on surface structure, surface chemistry and contact time; when the pair is separated by an insulating gap, then the pair does not pass a current. When the contacts touch, the switch is "closed"; when the contacts are separated, the switch is "open". The gap must be an insulating medium such as air, vacuum, oil, SF6 or other electrically insulating fluid. Contacts may be operated by humans in push-buttons and switches, by mechanical pressure in sensors or machine cams, and electromechanically in relays. The surfaces where contacts touch are usually composed of metals such as silver or gold alloys that have high electrical conductivity, wear resistance, oxidation resistance and other properties. Beyond the contact surface and immediate area, the electrical contact is usually composed of other metals for mechanical and cost reasons.

Even when contacts are separated, there may be conduction due to insulation resistance, arcing or a glow discharge.

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