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

UM-0018-H Ultra Miniature Reed Switch

UM-0018-H Ultra Miniature Reed Switch Drawing

All dimensions in mm

UM-0018-H Cropped reed switch UM-0018-H SMD reed switch UM-0018-H Vertical Mount reed switch UM-0018-H Horizontal Mount reed switch

Click thumbnails to view actuation distances.


7.0 mm glass size Omni-polar 10W Contact rating Does not require power for operation Normally Open, Form A contact  Sputtered Ruthenium contact Inert gas filled glass capsule Four formations Tin plated leads  RoHS Compliant and Lead-free  Not Sensitive to ESD


These highly sensitive, Form A reed switches are designed for low power, high speed switching applications. The 7 mm glass version is built for lower Contact Resistance and can switch higher loads. The flattened leads are useful for orienting all reed switches in a batch, in one way, while soldering, welding etc., for maximum in-group sensitivity. This reed switch is completely Lead-free and conforms to the RoHS directive. The cropped version is suitable for smaller plastic housings and can be soldered to cables, the SMD version is suitable for reflow on PCBs, and the vertical and horizontal mount versions are suitable for mounting on through hole PCBs. Information on tolerances for these formations can be found here.


Glass Length mm 7.0
Operate Range AT 7-20
Release Range AT 3-18
Contact Rating (max) W/VA 10.0
Switching Current (max) A 0.5
Carry Current (max) A 0.5
DC Switching Voltage (max) VDC 100
AC Switching Voltage (max) VAC 70
Breakdown Voltage (min) VDC 150
Contact Resistance (max) 200
Insulation Resistance (min) Ω 109
Capacitance (min) pF 0.2


Operate Time (max) ms 0.35
Bounce Time (max) ms 0.3
Release Time (max) ms 0.1
Resonance Frequency Hz >2000
Operating Frequency Hz 500
Operating Temperature °C -40 to +120
Shock Resistance (½Sin wave for 11ms) G 30
Vibration Resistance (10-2000Hz) G 20
Test Coil Code 717 102 003

Ordering Code

UM-0018-H-(Start Operate AT)-(Finish Operate AT)-(Lead Formation code)

Formation Code C S V H
Cropped SMD Vertical Mount Horizontal Mount

Ordering Code Examples

UM-0018-H-7-12 denotes 7-12 Operate AT with unmodified leads
UM-0018-H-15-18-S denotes 15-18 Operate AT band with SMD formed leads

Handling of Reed Switches

Dropping Reed switch Reed Switches are sensitive devices that easily develop micro cracks in the glass to metal seals when subjected to external...Continue reading ->


Reed Switch cropping Reed switch leads may need to be cropped for use in custom plastic housings, after soldering with external cables. Cropping...Continue reading ->

Soldering Guide

Soldered Reed switch Manual Soldering of reed switch leads may be required when using custom plastic housing with external cables. The reed switches...Continue reading ->

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...Continue reading ->

Potting and Encapsulation

Dispensing unit When potting or encapsulating reed switch assemblies in custom housings, selection of materials are important. The specification of epoxy or...Continue reading ->

Other Special Configurations Available

Lower Static Contact Resistance
Dynamic Contact Resistance Limit
Higher Insulation Resistance
Special Release Limits
Gold plated leads


Although we can never restrict the use of a reed switch to a particular field, the following is a list of some of the applications that the UM-0018-H reed switch is known to perform well.

Reed sensors for detecting key in ignition

key ignition Automobile Key An Ignition switch on an automobile comes in two types, a manual key or a start button as...Continue reading ->

Reed switches in Lightsabers

Light Saber Light Sabers are weapons used by the Jedi and the Sith, in the fictional Star Wars Universe, set...Continue reading ->

Magnet sensors in Musical Greeting Cards

Reed switches in musical greeting card Greeting Card Even in the digital age of Smart phones, people do like to mail out or hand over greeting...Continue reading ->

Reed sensors in Radio-controlled Gliders and model Airplanes

Reed switches in model airplanes Model Airplane Radio controlled aircrafts, gliders and helicopters come in various sizes from simple ones with few controls to more...Continue reading ->

Reed sensors in Accurate level sensing of fluids

Reed switches in fluid level sensing Fuel Gauge In ships and yachts, it is not only necessary to monitor the exact volume of fuel, but also...Continue reading ->

Reed switches in Washing machine vibration detection

Reed switches in washing machine Washing Machine Reed Switches are used in the assembly and manufacture of bi-directional vibration sensors. A magnet and a very...Continue reading ->

Reed sensors in Motor direction changing in Electric Toothbrushes

Reed switches in electric toothbrush Electric Toothbrush Electric toothbrushes are designed to make the brush head and bristles move in rapid motions, either in a...Continue reading ->

Reed switches and Reed sensors in Spirometers

Spirometer Spirometer A Lung function test or Pulmonary Function test, PFT for short, is a system to evaluate the respiration system...Continue reading ->

Miniature Reed sensors in activating Dentist’s Drills

Dentist Drill Denstist's Drill A Dentist's Drill is a small hand held contraption used by dentists to drill or polish teeth. It...Continue reading ->
UM-0018-H 10W Ultra Miniature Reed Switches
7.0mm x ø1.80mm, complete data sheet and technical specifications. This Reed Switch supersedes TRA 2212 and TRA 2213 and can be considered a direct equivalent. Customers can safely use UM-0018-H in place of MITI-3V1, ORD 213, KSK-1A80, RI 70, RD-18B, HSR-023R or MKA-07101.
Brand: RRE
Manufacturer: Reed Relays and Electronics
Model: UM-0018-H
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