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

R2B, Normally Closed, SMD Reed Sensor

  • R2B-S NC Reed Sensor Drawing
  • Drawing of R2-S Reed Sensor Pad Layout
  • R2B-F NC Reed Sensor Drawing
  • Drawing of R2-F Reed Sensor Pad Layout
  • R2B NC Reed Sensor Carrier Tape Drawing


10W Contact Rating. Normally Closed contact. Polarity Sensitive. Two sensitivity bands. Two Lead formations.



Does not require power for operation. Sputtered Ruthenium Contact. Not ESD Sensitive. Packed in Tapes for automatic assembly.


These Normally Closed SMD reed sensors are built with an inbuilt biasing magnet. As they are molded with pre-flattened leads, no shock is transferred into the device when SMD formation takes place. Various activating distances are available depending on the magnet and the AT band used. The sensors are tested 100% for release and operate AT, Static Contact Resistance and Variable Contact Resistance before packing. Opposing poles of magnet and sensor cause this normally closed sensor contact to release. Like poles do not cause a release. Choosing the right AT band, magnet strength, and operating axis, will restrict the number of operates and releases to one. All dimensions are in mm.

Cylindrical and Rectangular Magnets

Standard magnets-RRE Drawing of Cylindrical MagnetsDrawing of Rectangular Bar Magnets starFeaturesNdFeB High Energy. Nickel coated. Energized Continue reading ->

Nov 18, 2020

Actuation Distances for R2B NC Reed Sensors

Standard Size Biased Reed Sensor Operate and release distances for the R2B Normally closed reed sensor in the two standard AT bands when actuated with NdFeB standard Continue reading ->

Oct 30, 2020


Contact FormB
Contact Rating (max)W/VA10.0
Switching Current (max)A0.5
Carry Current (max)A1.50
DC Switching Voltage (max)VDC180
Breakdown Voltage (min)VDC200
Contact Resistance (max)150
Insulation Resistance (min)Ω109
Capacitance (typ)pF0.2


Operate Time (max)ms0.35
Bounce Time (max)ms0.15
Release Time (max)ms0.15
Resonance Frequency (typ)Hz>2000
Operating Frequency (max)Hz500
Operating Temperature Range°C-40 to +140
Shock Resistance (½Sin wave for 11ms)G30
Vibration Resistance (10-2000 Hz)G20

Ordering Code

R2B-(Formation Code)-(Release Band Code)

Formation CodeLead Type
SGull-wing SMD
FLow Profile SMD
Release Band Code

Examples: R2B-S-2 denotes R2B Reed Sensor with Gull-wing SMD formed leads, in 15-20 Release Band (AT). R2B-F-1 denotes R2B Reed Sensor with Low profile SMD formed leads, in 10-15 Release Band (AT).

Other Special Configurations: Lower Static Contact Resistance, Dynamic Contact Resistance Limit, Higher Insulation Resistance, Special Release Limits, Gold plated leads.

Usage Notes

Here are some of the recommended usage notes to ensure maximum durability of this product. The complete usage notes are available here.

Ampere Turn Selection

Reed Sensor Manufacturer Cross Reference For any application, it is important to select the correct Ampere Turn (AT) or magnetic sensitivity of a Reed Switch, Reed Sensor or Continue reading ->

Aug 27, 2020

Product Handling

Dropping Reed switch Reed Switch Handling Reed Switches, Reed Sensor and Magnet Sensors are sensitive devices that easily develop micro cracks in the glass Continue reading ->

Aug 31, 2020

Reflow Soldering

Drawing of SMD reflow soldering curve Reflow Soldering is a process of automatically soldering multiple devices on a PCB. This is usually done after components are Continue reading ->

Aug 28, 2020

Manual Soldering

Soldered Reed switch Soldering of Reed Switches and Reed Sensors requires some care to ensure that these delicate devices are not inadvertently damaged. Damage Continue reading ->

Nov 10, 2020

Ferro-magnetic parts

Ferromagnetic parts Reed Switches use an alloy of Nickel and Iron with a few other elements that make the alloy Ferro-magnetic and having a low Remanence. Continue reading ->

Sep 4, 2019

Reed Contact Protection Circuits

Inductive Load Protection Circuit It is assumed that the ideal reed switch load is a Resistive Load, but it is almost impossible to reduce any load to purely resistive. Continue reading ->

Aug 31, 2020


Although we can never restrict the use of a reed sensor to a particular field, the following is a list of some of the applications that the R2B Normally Closed Reed Sensor is known to perform well.

Reed Sensors in In-road Warning Lights

In-road Warning Lights In-road warning lights Road traffic control devices or In-road Warning Lights, are markers, signs and signal devices used to inform, Continue reading ->

Dec 1, 2020

Reed switches in Safety Vane applications

conveyor belt Conveyor Vane The automation industry depends on feeding systems which feed parts of different shapes into the assembly machine. The Continue reading ->

Nov 7, 2020

Reed sensors in Emergency lamp holders

Reed switches in emergency lamp Emergency Lamps Emergency lamps are rechargeable battery powered lamp that automatically turn on when there is a mains power outage. Continue reading ->

Nov 7, 2020

Reed sensors in Survival rafts and ELTs

Reed switches in survival rafts Emergency Raft Survival rafts contain water sensors which trigger the compressed air cylinder to inflate the raft when dropped into the Continue reading ->

Nov 7, 2020

Reed sensors used in Fuel cap position sensing

Automobile Fuel cap Automobile fuel cap open A dashboard or an instrument panel located in front of the automobile driver and displays instrumentation and Continue reading ->

Nov 7, 2020

Reed sensors in Telephone Handsets

Reed switches in telephone hook switches Telephone Handset Even though the telephone was ubiquitous in the 80s and 90s even every home or office, it has been replaced with Continue reading ->

Nov 20, 2020

R2B, Normally Closed, SMD Reed Sensor
R2B Normally Closed (NC) SMT Reed Sensors: 19.5 mm pitch gull wing, polarity sensitive, complete data sheet and technical specifications.
Brand: RRE
Manufacturer: Reed Relays and Electronics
Model: R2B
4.1 based on 4 reviews