(from top) Single-pole reed switch, four-pole reed switch and single-pole reed relay. Scale in centimeters.
A reed relay[i] is a type of relay that uses an electromagnet to control one or more reed switches. The contacts are of magnetic material and the electromagnet acts directly on them without requiring an armature to move them. Sealed in a long, narrow glass tube, the contacts are protected from corrosion. The glass envelope may contain multiple reed switches or multiple reed switches can be inserted into a single bobbin and actuate simultaneously. Reed switches have been manufactured since the 1930s.
Compared with armature-based relays, reed relays can switch much faster, as the moving parts are small and lightweight, although switch bounce is still present.[1] Also, they require less operating power and have lower contact capacitance. Their current handling capacity is limited but, with appropriate contact materials, they are suitable for "dry" switching applications. They are mechanically simple, making for reliability and long life.
Cite error: There are <ref group=lower-roman> tags or {{efn-lr}} templates on this page, but the references will not show without a {{reflist|group=lower-roman}} template or {{notelist-lr}} template (see the help page).
^Cite error: The named reference Hewes_2013 was invoked but never defined (see the help page).
A reedrelay is a type of relay that uses an electromagnet to control one or more reed switches. The contacts are of magnetic material and the electromagnet...
at Bell Telephone Laboratories in 1936 by Walter B. Ellwood into the reedrelay. In its simplest and most common form, it consists of a pair of ferromagnetic...
alternatives, they are now comparatively uncommon. A mercury-wetted reedrelay is a form of reedrelay that employs a mercury switch, in which the contacts are wetted...
decoding Reedrelay, one or more reed switches controlled by an electromagnet Reed switch, an electrical switch operated by an applied magnetic field Reed valve...
example, a reedrelay matrix switch is normally switched with all contacts dry. After the contacts are all connected, a wire spring relay is energized...
relay is used instead. This combines the speed of a low-mass relay, together with the fast wetting of mercury contacts. A relay, usually a reedrelay...
core, making them magnetically latching relays, similar to the ferreed and remreed types of reedrelay. Reedrelays are smaller and cheaper, thus better...
switching systems in the 1960s were not entirely digital in nature, but used reedrelay-operated metallic paths or crossbar switches operated by stored program...
force due to rate of rotation Relay or contactor – Electro-mechanically operated switch (see also solid state relay above) Reed switch – Magnetically activated...
reduced to reset the relay. A variant application of the attraction principle is the plunger-type or solenoid operator. A reedrelay is another example...
style Rotary switch, 1P4T, make-before-break, shorting style Reed switch, normally open Relays symbols are a combination of an inductor symbol and switch...
example, diodes are used in (stepper motor and H-bridge) motor controller and relay circuits to de-energize coils rapidly without the damaging voltage spikes...
rate-of-climb instrument, the electronic variometer, or serve as a timer for a relay as was formerly done in telephone exchanges. The electrical power input...
controlled reedrelays, and this looked promising. One of Ericsson's marketing points for crossbar was that it used precious-metal contacts, but reedrelays would...
applications could include those involving computer control of motors or relays, where the current is amplified from a safe low level of the computer output...
computers such as EDVAC tended to average eight hours between failures, whereas relay computers—such as the slower but earlier Harvard Mark I—failed very rarely...
container as the switching element. A mercury-wetted relay is a form of relay, usually a reedrelay, in which the contacts are wetted with mercury. These...
using technology such as crossbar or reedrelay, the register was often a system of analog electronics or even relay logic. The term "flash" or "hook flash"...
Global Information