Reed Switch Specifications | Reed Switch Manufacturers

This page covers Reed Switch basics with technical specifications of Reed Switch. It mentions Reed Switch manufacturers or vendors. Reed switch specifications include pull-in, drop out, maximum switching voltage, maximum switching current, maximum switching power etc.

What is Reed switch:
• It is magnetically activated mechanical switch.
• It consists of two metallic contacts enclosed in a small enclosure usually glass capsule.
• The contacts are magnetic and move in response to a magnetic field. Permanent magnet is needed to activate the switch.
• There are two types of reed switches viz. SPST and SPDT. Most common one is SPST which is either normally open or normally closed type.

Reed Switch construction and symbol

The figure-1 depicts reed switch construction and its symbol. Reed switches are available in following modes.
-Normally open
-Normally closed
-Bistable

Reed Switch specifications

Following reed switch specifications are considered during reed switch selection.

Pull-in: The minimum magnetic field strength required to activate the switch, often measured in ampere-turns. In other words, it is the magnetic field strength at which the reed switch is activated.

Drop-Out: The maximum magnetic field strength which allows the contacts of the switch to relax. In other words, it is the magnetic field strength at which the reed switch is de-activated. It is also measured in ampere turns. Pull-in will be higher in value than drop-out.

Maximum switching Voltage: It is the maximum voltage at which contacts can be switched. It is a reference voltage to determine contact switching performance.

Maximum Switching Current: It is the maximum current at which contacts can be switched. It is a reference voltage to determine contact switching performance.

Maximum Carry Current: It is the maximum current which can flow continuously over the closed contact.

Maximum switching Power: A reed switch can be used with alternating current. Hence its switching capability may be expressed in watts or VA.

Reed Switch Manufacturers

Following table lists popular Reed switch manufacturers or vendors.

Reed switch Manufacturers Description
HSI Sensing, 3100 NORGE ROAD, CHICKASHA, OK 73018 , USA The company manufactures reed switches for various applications across different industries. They offer reed switch of different types viz. form A (SPST, normally open), form B (SPST, normally close) and form C (SPDT, single pole double throw, break before make).
Littelfuse Inc. Chicago, IL, 60631 USA The company offers wide range of magnetically operated reed switches. They are available in bare glass and overmolded packages with variety of specifications (mechanical, electrical, magnetic).
Reed Relays and Electronics India Limited, Anekal-Gumlapuram Road, Thally 635118, India The company manufactures reed switches for various applications with round glass tubes and wire to achieve maximum seal strength.
Standex Electronics, Inc. The company offers magnetic reed switches designed to address various specific applications. It includes high frequency reed switch, high voltage reed switch, high power reed switch, SMD reed switch and so on.
STG Germany The company offers reed switches with glass tube having 7 to 50 mm length. The switches are available for switching capacities up to 120 W/VA, switching voltages from 0 to 10KV AC/DC and switching currents from 0 to 3 A AC/DC.
Comus International, NJ, USA Reed switches of different types are manufactured by Comus International.


Reed Switch Related Links

Reed Switch advantages and disadvantages
How Reed Switch works
Transformer basics and types
Relay
Reed Switch basics
SCR or thyristor


Useful product vendors or manufacturers

RF and Wireless tutorials