Sensors Catalog, Design Guide Datasheet by Littelfuse Inc.

View All Related Products | Download PDF Datasheet
% Littelfuse"
PRODUCT
CATALOG &
DESIGN GUIDE
Proximity | Level | Speed | Flow
© 2017 Littelfuse, Inc. • Specifications are subject to change without noticeLittelfuse.com 1
About This Guide
This guide provides an introduction to magnetic sensing and options for value-added
custom design packages. It also offers practical suggestions for selecting reed switches,
reed sensors and Hall effect sensors for a variety of applications.
Topic Page
Introduction to Magnetic Sensing 2–3
Value-Added Customization 4
Reed Switches 5-6
Hall Effect Sensors 8
Reed Sensors 9-10
Reed Relays 11
Magnetic Actuators 12
Applications 1316
% Littelfuse’ Wampum \ Answusmllumd V \ I mow Lmzliuu. Inc «mm-um... :uhlzctm cmngzwm‘nmnnhc:
© 2017 Littelfuse, Inc. • Specifications are subject to change without noticeLittelfuse.com 2
59010
(Ultra-Mini Firecracker)
MDCG-4
(Reed Switch)
59050
(Overmolded Reed Switch)
55140
(Flange Mount
Hall Effect
Sensor)
59135
(High-Temperature
Flange Mount
Reed Sensor)
WHY CHOOSE LITTELFUSE
Founded in 1927, Littelfuse has become the world’s most respected circuit protection
brand with well-established and growing platforms in power control and sensing
technologies. Today, we are a global company, offering the industry’s most diverse
and extensive product portfolio—fuses, semiconductors, polymers, ceramics, relays,
sensors and more—serving the electronics, automotive and industrial markets. Each
is manufactured to exacting quality standards and backed by an unwavering
commitment to technical support and customer service.
Our history of innovation, combined with our customer-first culture, drives us to
collaborate with you to develop safer, more reliable products that are energy efficient
and compliant with global regulations. We will partner with you to solve complex
problems wherever electrical energy is used, bringing design, engineering and
technical expertise to deliver business results.
WHY CHOOSE LITTELFUSE SENSORS?
Our product designs are manufactured to our high standards and backed by experts
committed to delivering the best solutions for your specific needs. Our global
organization provides:
n Custom sensor designs per customer specifications
n Vertically integrated manufacturing
n In-house magnetic simulation support
n Quick turnaround for custom sensor prototypes
Your Single Source
Littelfuse offers a diverse magnetic sensor line. If we do not have a standard sensor that
meets your needs, we will work with you to develop a forward-thinking solution that
does. Our goal is to offer you a comprehensive range of options so you’ll never have to
make compromises in your designs.
Testing Support
Through our network of Global Labs in China, Germany, Italy, Japan, Lithuania, Mexico,
the Philippines and the United States, we design innovative solutions and provide
customer applications support and testing. Our unique capabilities include performance
testing, material analysis and regulatory compliance testing. The dedication of our Global
Labs ensures the outstanding performance, safety and reliability of our products and
support services for our worldwide customer base.
Application Knowledge
At Littelfuse, our expertise involves applying reliable and efficient product solutions,
innovative technologies and global resources to address technical challenges in a variety
of applications. A worldwide network of research teams focuses on product development
and support, design-in programs and application testing in our Global Labs.
Global Support
With more than 10,000 employees in over 40 locations throughout the Americas, Europe
and Asia, Littelfuse products, applications knowledge and technical support are available
around the globe. Our network of regional customer support offices and hundreds of
authorized distributors works to help you solve problems quickly.
For more information, please visit: www.littelfuse.com/contactus.
Quality Assurance
Our global manufacturing facilities abide by strict
quality assurance requirements and hold the following
quality management system registrations:
: fig: {a
© 2017 Littelfuse, Inc. • Specifications are subject to change without noticeLittelfuse.com 3
REED SWITCHES
A reed switch has two ferromagnetic blades (reeds) contained within a tubular glass envelope that
is hermetically sealed at each end. The contacts on each reed blade have a thin layer of precious metal
material deposited on them. There is usually nitrogen gas on the inside of the glass envelope to eliminate
the presence of oxygen and ensure that the contacts will not oxidize. Reed switches are activated
by a permanent magnet or an electromagnet. The reed switch and magnetic field combination
is commonly known as the “magnetic circuit.
The relative stiffness of the reed
blades along with the small gap
and overlap between the two
contacts controls the sensitivity
of the reed switch. The sensitivity
of the switch is the amount of
magnetic field that is required to
actuate the contact into an open
or closed mode. It is measured in
units of ampere-turns (AT). Most
reed switches have a sensitivity
range of 10–30 AT, where 10 AT
is more sensitive than 30 AT.
REED SENSORS
Reed sensors are reed switches that are packaged within an external housing for simplified mounting/
connecting and additional protection against environmental influences. These sensors are typically
mounted in mechanical systems. A bare reed switch can easily be mounted on circuit boards. However,
for an application such as a door security sensor, the reed switch needs a protective shell/housing
for handling and mounting. These packages offer resistance to mechanical stress by protecting
the bare glass of the reed switch.
REED RELAYS
A reed relay is made by combining a reed switch with a copper coil. Like other relays, this provides
galvanic isolation between the coil input and the controlled contact(s). However, because of the small size
and magnetic efficiency of the reed switch, the power required to drive the coil is lower than most other
types of relays. Other advantages include high insulation resistance, low contact resistance and long
contact life. Reed relays are used in many applications, including automotive, test equipment, security,
medical and process control equipment.
HALL EFFECT SENSORS
A Hall effect device is a semiconductor-based integrated circuit with Hall plates that respond to
magnetic fields. Additional circuitry is added for power supply and signal conditioning, temperature
compensation and EMC/ESD protection. Hall effect devices provide digital or analog output signals
that are used for proximity and continuous rotary or linear positioning. Unlike a reed switch, a Hall
effect device contains active circuitry, so it draws a small amount of current at all times. Hall effect
devices come in two- or three-wire versions. Some devices are programmable.
MAGNETIC ACTUATORS
Littelfuse offers a wide range of magnetic actuators that are packaged in shapes similar to the relative
mating sensors. We also offer a limited family of bare magnets with various grades of materials,
including ferrite (ceramic), AlNiCo and neodymium iron boron (NdFeB) materials.
Comparing Reed vs. Hall Effect
Although there are differences between reed switch
and Hall effect technologies, both platforms offer
practical advantages for various applications. Here
is a comparison of the benefits of each technology.
Figure 1-Magnetic field lines
must be aligned parallel to a
reed switch’s contacts in order
to open/close the contacts
SN
S
NS
N
SN
S
N
S
N
SNS
N
S
N
OPEN
Hold
Close
MAGNET
-X
mm X
mm
X
-X
O
Y
mm
SN
Y
Figure 2-Two-pole linear activation,
parallel orientation
OPEN
Hold
Close
MAGNET
-X
mm X
mm
X
-X
O
Y
mm
S
N
Y
Close
OPEN
Hold
Figure 3-Single-pole linear activation,
perpendicular orientation
INTRODUCTION TO MAGNETIC SENSING
Reed Switch Hall Effect Sensor
Noncontact sensing element
Zero power consumption
High-Frequency operation
Digital switching
Linear sensing
Integrated circuitry
Ultra-small package size
Electrical load capability
EMC/ESD immunity
© 2017 Littelfuse, Inc. • Specifications are subject to change without noticeLittelfuse.com 4
Plastic Assembly
Injection Molding
Ultrasonic Welding
Heat Staking
Assembly Methods
Automated
Cellular
Manual
100% End of Line Testing
Hermetic Seal Test
Magnetic Actuation
Contact Resistance
Circuit Board Assembly
Vision Systems
In- Circuit-Test
Pick and Place
Reflow soldering
Wave soldering
Robotic soldering
Encapsulation
Transfer Over-Mold
Low-Pressure Over-mold
Epoxy/Urethane Potting
Meter/Mix Dispensing
Custom Magnet Solutions
Magnetic simulation and modeling for
customer specific designs
Integral magnets within the sensor
Magnetic circuits with tight tolerances available
Magnetic actuation mapping
Reed Switch and Hall Effect
Automatic Switch Assembly Machines
Custom reed switch forming equipment
Automated Testing
Automatic Cut and Form
Tape + Reel packaging for SMD and other
custom design requirements.
Wire Harness and Termination
Equipment
Automatic Cut, Strip, and Crimp
Apply customer-specified
wire/cable and connectors
Over-molding of connector to
wire/cable sealing options available
TYPES OF CUSTOMIZATION
Modifications are available to existing standard product packages, such as adding connectors or changing
wire size or length, as well as offering special reed switch sensitivities, custom lead forming and bending
or modifications to bare reed switches.
Fully new custom sensor package designs and/or circuitry
Magnetic circuit (actuator magnet and sensor) design for a variety of applications
See our full range of sensor manufacturing process capabilities
ENGINEERING SERVICES OFFERED:
˚3D CAD mechanical design services
˚Electronic circuitry design
˚Magnetic simulation support analyzing feasibility of the design options
˚3D mapping of magnetic actuation of the sensor
˚Rapid prototyping and quick-turn concept parts including 3D printed parts
˚Prototype units using prototype tooling
˚Reliability/Validation testing options
˚Fully designed production capable sensor and tooling
DESIGNING YOUR CUSTOM SENSOR
Littelfuse specializes in custom design packages that meet our customer needs
for both Reed and Hall Effect Sensor designs.
Our manufacturing processes are vertically integrated.
Littelfuses dedicated application engineers are available to assist you in every step
of the custom product development process. Contact our sensor application experts
today at http://www.littelfuse.com/sensorscontact.
SENSOR MANUFACTURING PROCESS CAPABILITIES
CUSTOMIZABLE OPTIONS
% Litteltuse” um \ AnxwuxDelweved Exnevhxe Ann
© 2017 Littelfuse, Inc. • Specifications are subject to change without noticeLittelfuse.com 5
Power Size Terminals Switch Type Package Product Series
Body Length
(mm)/[Inch]
Lead-Lead Length
(mm)/[Inch]
Low Power
Small
Leads
A: SPST-NO Glass MITI-3V1 7.0 0 [. 276] 4 6 .0 0 [1.811]
A: SPST-NO Glass MDSR-10 10.16 [. 40 0] 40.38 [1.590]
A: SPST-NO Glass MDSR-7 12.70 [.500] 40.38 [1.590]
SMD
A: SPST-NO Glass MISM-3V1 7.0 0 [.276] 13.72 [.540]
A: SPST-NO Glass MDSM-10 10.16 [.40 0] 15.62 [.615]
Medium
Leads
A: SPST-NO Glass FLEX-14 14.0 0 [.551] 44.30 [1.744]
A: SPST-NO Glass MDCG-4 15.24 [.600] 40.38 [1.590]
A: SPST-NO Glass MACD-14 14.0 0 [.551] 44.30 [1.744]
C: SPDT-CO Glass MDRR-DT 14.73 [.580] 51.66 [2.034]
SMD
A: SPST-NO Glass MDSM-4 15.24 [.600] 19.30 [.760]
A: SPST-NO Glass MASM-14 14.00 [.551] 44.30 [1.744]
C: SPDT-CO Glass MDSM-DT 14.73 [.580] 25.40 [1.00]
Both Leads
and SMD
A: SPST-NO Overmolded 59165 16.00 [.630] 20.20 [.795]
A: SPST-NO Overmolded 59166 16.00 [.630] 19.51 [.768]
A: SPST-NO Overmolded 59170 11.43 [.450] 16.25 [.640]
Leads
A: SPST-NO Overmolded 59045-1 17.78 [.700] 15.24 [.600]
A: SPST-NO Overmolded 59050-1 22.86 [.900] 20.32 [.800]
High Power
Medium
Leads
A: SPST-NO Glass H A15 -2 15.24 [.600] 40.38 [1.590]
A: SPST-NO Glass MLRR-4 15.24 [.600] 40.38 [1.590]
A: SPST-NO Glass MLRR-3 15.24 [.600] 56.64 [2.230]
A: SPST-NO Glass MVSR-20 19.69 [0.775] 56.77 [2.235]
SMD
A: SPST-NO Glass MLSM-4 15.24 [.600] 19.56 [.770]
A: SPST-NO Glass MLSM-3 15.24 [.600] 19.56 [.770]
Leads
A: SPST-NO Overmolded 59050-2 22.86 [.900] 20.32 [.800]
A: SPST-NO Glass MRPR-20 20.32 [.800] 56.64 [2.230]
Large
A: SPST-NO Glass DRS-50 50.80 [2.000] 82.55 [3.250]
C: SPDT-CO Glass DRS-DTH 39.67 [1.562] 85.73 [3.375]
MACD-14
MITI-3V1
MDSM-10
DRS-DTH
Notes:
For details on electrical specifications, visit littelfuse.com
A:SPST-NO - Single Pole Single Throw - Normally Open
C:SPDT-CO - Single Pole Double Throw - Change Over
All reed switches are RoHS compliant
*Certification: Contact Littelfuse for certified ratings
**Breakdown Voltage – per MIL-STD-202, Method 301
20 W for 100-265 VAC loads, 10 W for all other loads
REED SWITCHES
he "gm /, awn: / I / Dull! y// 3 in"! 9“": cflu; flu: emu: cflu; null: null: emu: cflu; nun: awn: smut cflu; cw“ awn: own: MM: EN": awn: cw": MM: cum
© 2017 Littelfuse, Inc. • Specifications are subject to change without noticeLittelfuse.com 6
Switching
Power (W)
Switching
Voltage (V)
Breakdown
Voltage**
(Vdc - min.)
Switching
Current (A)
Contact
Resistance (Ω)
Operating
Temperature (°C)
Magnetic
Sensitivity (AT) Certification*
10 170 Vdc, 120 Vac 175 0.25 Adc, 0.18 Aac 0.15 -40 to +125 6-10
10 200 Vdc, 140 Vac 250 0.5 Adc, 0.35 Aac 0.12 -40 to +125 10-25
10 200 Vdc, 140 Vac 250 0.5 Adc, 0.35 Aac 0.1 -40 to +125 10-25
10 170 Vdc, 120 Vac 175 0.25 Adc, 0.18 Aac 0.15 -40 to +125 6-10
10 200 Vdc, 140 Vac 250 0.5 Adc, 0.35 Aac 0.12 -40 to +125 10-25
10 200 Vdc, 140 Vac 250 0.5 Adc, 0.35 Aac 0.1 -40 to +125 10-30
10 200 Vdc, 140 Vac 250 0.5 Adc, 0.35 Aac 0.1 -40 to +125 12- 38
10 200 Vdc, 140 Vac 200 0.5 Adc, 0.35 Aac 0.1 -40 to +125 10-30
5175 Vdc, 120 Vac 200 0.25 Adc, 0.18 Aac 0.1 -40 to +125 15-30
10 200 Vdc, 140 Vac 250 0.5 Adc, 0.35 Aac 0.1 -40 to +125 12- 38
10 200 Vdc, 140 Vac 200 0.5 Adc, 0.35 Aac 0.1 -40 to +125 10-30
5175 Vdc, 120 Vac 200 0.25 Adc, 0.18 Aac 0.1 -40 to +125 15-30
10 200 Vdc, 140 Vac 250 0.5 Adc, 0.35 Aac 0.1 -40 to +125 10-25
10 200 Vdc, 140 Vac 250 0.5 Adc, 0.35 Aac 0.1 -40 to +125 10-26
10 200 Vdc, 140 Vac 250 0.5 Adc, 0.35 Aac 0.15 -40 to +125 10-25
10 200 Vdc, 140 Vac 250 0.5 Adc, 0.35 Aac 0.2 -40 to +105 15-30
10 200 Vdc, 140 Vac 250 0.5 Adc, 0.35 Aac 0.2 -40 to +105 12-33
20200 Vdc, 265 Vac
400 0.4 Adc, 0.3 Aac
0.1 -20 to +125
17-23
450 0.5 Adc, 0.35 Aac 22-33
20 200 Vdc, 140 Vac 250 1.0 Adc, 0.7 Aac 0.1 -40 to +125 17-38
20 200 Vdc, 140 Vac 250 1.0 Adc, 0.7 Aac 0.1 -40 to +125 17-38
10 1000 Vdc 2000 0.5Adc,0.35 Aac 0.1 -75 to +125 17-38
20 200 Vdc, 140 Vac 250 1.0 Adc, 0.7 Aac 0.1 -40 to +125 17-38
20 200 Vdc, 140 Vac 250 1.0 Adc, 0.7 Aac 0.1 -40 to +125 17-38
20 200 Vdc, 265 Vac 400 0.5 Adc, 0.35 Aac 0.2 -20 to +105 17-33
50 250 Vdc, 265 Vac 750 1.5 Adc, 1.1 Aac 0.1 -20 to +125 17- 4 3
100 280 Vac, 400 Vdc 600 3.0 Adc, 2.1 Aac 0.1 -40 to +125 42-83
30 350 Vac, 500 Vdc 1200 0.50 Adc, 0.35 Aac 0.125 -20 to +125 50-80
59165
59045
MRPR-20
Applications Assistance and Custom Switch Modification
Littelfuse offers complete application engineering assistance in selecting the correct
switch, sensitivity, and configuration. Switch life is affected by electrical load and other
operating conditions. Littelfuse offers load/life information per customer request.
Lead Modifications
Littelfuse can cut and/or form the reed switch leads to meet
your dimensional requirements. Most lead modifications can
be done by Littelfuse without any additional tooling costs.
REED SWITCHES
% Litleltuse“ ExpemxaADnllzd \ Anxwux Damn
© 2017 Littelfuse, Inc. • Specifications are subject to change without noticeLittelfuse.com 7
Our sensor technologies are ideally suited for various sensing
applications, including proximity, level, speed and flow, as shown
in the table. Customizations, including various connectors and wire
lengths, are available for all our standard products.
For more detailed product specifications and all available options,
refer to the individual product datasheets.
Sensor Type Application
Proximity Level Speed Flow
Reed Switches
Hall Effect Sensors
Flat Pack
Round Flange Mount
Flat Flange Mount
Threaded Barrel
Rotary/Angular •
Reed Sensors
Firecracker • • •
Threaded Barrel
Flange/Flat Pack
Float •
Vane •
Lever Arm
Seat Occupancy
Sensors,
Reed Relays
and Magnetic
Actuators
% Littelfuse" [mm mm \ AnswL-v: mums r flange Muum Han Anz‘ug 553nm Hz! Pack Rmary HaH 553m Ha! Peak mgnal H3“ H0 H5 Th 551m ‘ LED Flange Muum HaH ‘ M Q
© 2017 Littelfuse, Inc. • Specifications are subject to change without noticeLittelfuse.com 8
FLAT PACK
This sensors rectangular package is ideally suited for mounting on a flat surface.
It is designed for use in a wide range of environments.
Product
Series Description
Overall Dimensions Operating
Supply
Voltage
Operating
Supply
Current Output
Type
Output
High
Output
Low
Temperature Rating
mm (inch) mA ˚C
L x W x H Vdc Max. Max. Operating Storage
55140
Flange Mount Hall, 2-Wire 23.00 (0.906) x 14.00 (0.551) x 6.00 (0.236) 3.75 to 24 N/A Current N/A 2.2 - 5.6 mA -40 to +100 -65 to +105
Flange Mount Hall, 3-Wire 23.00 (0.906) x 14.00 (0.551) x 6.00 (0.236) 3.8 to 24 N/A Voltage Sinking/Open
Collector 0.4 V @ 20 mA -40 to +100 -65 to +105
Flange Mount Hall, Analog 23.00 (0.906) x 14.00 (0.551) x 6.00 (0.236) 4.5 to 5.5 N/A Analog Voltage 4.65 V 0.35 V -40 to +100 -65 to +105
55300 Flat Pack Rotary Hall 28.50 (1.122) x 20.40 (0.803) x 6.35 (0.250) 4.5 to 5.5 16 Analog Voltage
or PWM 4.5 V 0.5 V -40 to +105 -65 to +105
55310 Flat Pack Digital Hall 28.50 (1.122) x 20.40 (0.803) x 6.35 (0.250) 4.75 to 24 6 Current N/A 20 mA -40 to +105 -65 to +105
ROUND FLANGE MOUNT
Its cylindrical package has a flat flange to accommodate mounting on a flat surface.
This sensor is ideally suited for sensing a rotating ferrous metal target.
Product
Series Description
Overall Dimensions Operating
Supply
Voltage
Operating
Supply
Current Output
Type
Output
High
Output
Low
Temperature Rating
mm (inch) ˚C
L x W x H Vdc mA Max. Operating Storage
55505 Flange Mount Geartooth Hall 17.86 (0.703) x 36.75 (1.447) x 41.40
(0.551) 4.75 to 24 N/A Digital Vdd-2 0.6 V @ 20
mA -40 to +125 -65 to +125
FLAT FLANGE MOUNT
The low-profile, rectangular package is designed for installation in small-gap spaces.
Product
Series Description
Overall Dimensions Operating
Supply
Voltage
Operating
Supply
Current Output
Type
Output
High
Output
Low
Temperature Rating
mm (inch) ˚C
L x W x H Vdc mA Max. Operating Storage
55100
Miniature Flange Mount Hall, 2-Wire 25.50 (1.004) x 11.00 (0.433) x 3.00 (0.118) 3.75 to 24 N/A Current N/A N/A -40 to +100 -65 to +105
Miniature Flange Mount Hall, 3-Wire 25.50 (1.004) x 11.00 (0.433) x 3.00 (0.118) 3.8 to 24 N/A Voltage Sinking/Open
Collector 0.4 V @ 10 mA -40 to +100 -65 to +105
Miniature Flange Mount Hall, Analog 25.50 (1.004) x 11.00 (0.433) x 3.00 (0.118) 4.5 to 5.5 N/A Analog Voltage 4.65 V 0.35 V -40 to +100 -65 to +105
55110 LED Flange Mount Hall 34.00 (1.399) x 14.00 (0.551) x 10.00 (0.394) 3.8 to 24 N/A Voltage Vdd-2 @ 0.1 mA 0.4 V @ 20 mA -40 to +85 -65 to +85
Product
Series Description
Overall Dimensions Operating
Supply
Voltage
Operating
Supply
Current Output
Type
Output
High
Output
Low
Temperature Rating
mm (inch) ˚C
Thread Pitch x L Vdc mA Max. Operating Storage
55075 Stainless Steel M12 Geartooth Hall M12 x 1 Pitch x 46.00 (1.811) 4.75 to 25.2 N/A Digital Vdd - 2 0.6 V @ 20 mA -40 to +85 -65 to +85
THREADED BARREL
Designed for harsh environments, this sensor may easily be mounted and adjusted
using the supplied retaining nuts. Its cylindrical package is available with metric threads.
Product
Series Description
Overall Dimensions Operating
Supply
Voltage
Operating
Supply
Current Output
Type
Output
High
Output
Low
Temperature Rating
mm (inch) ˚C
L x W x H Vdc mA Max. Operating Storage
55250 Rotary Hall 50.00 (1.968) x 37.30 (1.469) x 28.25 (1.112) 4.5 to 5.5 16 Analog Voltage
or PWM 4.5 V 0.5 V -40 to +125 -65 to +125
ROTARY/ANGULAR
This sensor is packaged with a magnet and a Hall effect sensing element.
It provides instantaneous angular position measurement.
HALL EFFECT SENSORS
% lltleltuse" ExnevhxeADnlled \ AnswevxDelweved mm: Sui- 55mm uszMm‘ Fwetvzzkev Press“ mekev, Nuvma Pressfllfwamzkev Chan mm Fwetvzzkev Norma ‘ V’- D m n
© 2017 Littelfuse, Inc. • Specifications are subject to change without noticeLittelfuse.com 9
Product
Series Description
Overall Dimensions Contact
Rating
Switching
Voltage
Breakdown
Voltage
Switching
Current
Contact
Resistance, Initial Mating
Actuator
mm (inch) W Vdc Vdc A Ohms
Ø x L Max. Max. Min. Max. Max.
59010 Ultra-Mini Firecracker 3.13 (0.123) x 9.00 (0.354) 10 170 175 0.25 0.25 57020
59020 Mini Firecracker 5.10 (0.201) x 15.24 (0.600) 10 170 175 0.25 0.25 57020
59021 Aluminum Mini Firecracker 5.10 (0.201) x 15.24 (0.600) 10 170 175 0.25 0.25 57020
59022
Firecracker, Normally Open 5.80 (.228) x 25.4 (1.000) 10 200 250 0.5 0.2
57022Firecracker, Changeover 5.80 (.228) x 25.4 (1.000) 5 175 200 0.25 0.2
Firecracker, Normally Closed 5.80 (.228) x 25.4 (1.000) 5 175 200 0.25 0.2
59025
Firecracker, Normally Open 6.22 (0.245) x 25.40 (1.000) 10 200 250 0.5 0.2
57025
Firecracker, Normally Open High Voltage 6.22 (0.245) x 25.40 (1.000) 10 300 450 0.5 0.2
Firecracker, Changeover 6.22 (0.245) x 25.40 (1.000) 5 175 200 0.25 0.2
Firecracker, Normally Closed 6.22 (0.245) x 25.40 (1.000) 5 175 200 0.25 0.2
59030
Firecracker, Normally Open 6.22 (0.245) x 38.10 (1.500) 10 200 250 0.5 0.2
57030
Firecracker, Normally Open High Voltage 6.22 (0.245) x 38.10 (1.500) 10 300 450 0.5 0.2
Firecracker, Changeover 6.22 (0.245) x 38.10 (1.500) 5 175 200 0.25 0.2
Firecracker, Normally Closed 6.22 (0.245) x 38.10 (1.500) 5 175 200 0.25 0.2
59040
Press-Fit Firecracker, Normally Open 9.5 (0.375) Hole Ø x 31.00 (1.220) 10 200 250 0.5 0.2
57040Press-Fit Firecracker, Changeover 9.5 (0.375) Hole Ø x 31.00 (1.220) 5 175 200 0.25 0.2
Press-Fit Firecracker, Normally Closed 9.5 (0.375) Hole Ø x 31.00 (1.220) 5 175 200 0.25 0.2
FIRECRACKER
This sensor offers a slim, cylindrical package that is suitable for mounting on a frame.
Product
Series Description
Overall Dimensions Contact
Rating
Switching
Voltage
Breakdown
Voltage
Switching
Current
Contact
Resistance, Initial
mm (inch) W Vdc Vdc A Ohms
Ø x L Max. Max. Min. Max. Max.
59630
Float Sensor, Normally Open 23.70 (0.930) x 43.70 (1.720) 10 200 250 0.5 0.2
Float Sensor, Normally Open High Voltage 23.70 (0.930) x 43.70 (1.720) 10 300 450 0.5 0.2
Float Sensor, Changeover 23.70 (0.930) x 43.70 (1.720) 5 175 200 0.25 0.2
Float Sensor, Normally Closed 23.70 (0.930) x 43.70 (1.720) 10 200 250 0.5 0.2
59300 Level Sensor, Normally Open (Float Not Included) 19.90 (0.783) x 67.55 (2.660) 10 200 250 0.5 0.2
FLOAT
Designed for liquid-level sensing applications, this sensor has an integral float
magnet and a reed switch.
Product
Series Description
Overall Dimensions Contact
Rating
Switching
Voltage
Breakdown
Voltage
Switching
Current
Contact
Resistance, Initial
mm (inch) W Vdc Vdc A Ohms
L x W x H Max. Max. Min. Max. Max.
59085
Vane Sensor, Normally Open 25.40 (1.000) x 19.05 (0.750) x 6.35 (0.250) 5 175 200 0.25 0.2
Vane Sensor, Changeover 25.40 (1.000) x 19.05 (0.750) x 6.35 (0.250) 5 175 200 0.25 0.2
Vane Sensor, Normally Closed 25.40 (1.000) x 19.05 (0.750) x 6.35 (0.250) 10 200 250 0.5 0.2
Vane Sensor, Normally Closed High Voltage 25.40 (1.000) x 19.05 (0.750) x 6.35 (0.250) 10 300 450 0.5 0.2
59086
Vane Sensor, Normally Open 25.40 (1.000) x 19.05 (0.750) x 6.35 (0.250) 5 175 200 0.25 0.2
Vane Sensor, Changeover 25.40 (1.000) x 19.05 (0.750) x 6.35 (0.250) 5 175 200 0.25 0.2
Vane Sensor, Normally Closed 25.40 (1.000) x 19.05 (0.750) x 6.35 (0.250) 10 200 250 0.5 0.2
Vane Sensor, Normally Closed High Voltage 25.40 (1.000) x 19.05 (0.750) x 6.35 (0.250) 10 300 450 0.5 0.2
59090
Heavy Duty Vane Sensor, Normally Closed 32.50 (1.280) x 32.25 (1.271) x 23.25 (0.915) 10 200 250 0.5 0.2
Heavy Duty Vane Sensor, Normally Closed High Voltage 32.50 (1.280) x 32.25 (1.271) x 23.25 (0.915) 10 300 450 0.5 0.2
Heavy Duty Vane Sensor, Changeover 32.50 (1.280) x 32.25 (1.271) x 23.25 (0.915) 5 175 200 0.25 0.2
VANE
Packaged with a magnet and a reed switch, this sensor is typically used in applications
with a moving ferrous metal part.
Product
Series Description
Overall Dimensions Contact
Rating
Switching
Voltage
Breakdown
Voltage
Switching
Current
Contact
Resistance, Initial
mm (inch) W Vdc Vdc A Ohms
L x W x H Max. Max. Min. Max. Max.
59250 Push-button Seat Sensor (Reed) 32.51 (1.280) x 26.67 (1.050) x 37.34 (1.470) 10 200 250 0.5 0.2
59251 Seat Sensor with Dome (Reed) 108.20 (4.260) x 69.85 (2.750) x 39.88 (1.570) 10 200 250 0.5 0.2
SEAT OCCUPANCY
Packaged with an integral magnet and a reed switch, this sensor is available in
a push-button configuration or a dome configuration for weight/load distribution.
REED SENSORS
TH um % Littelfuse" [mm mm \ AnswL-v: mums "31?: mum... SIaWeSS SIEE‘ "weaned Banz‘ 327150! 55“ Heavy Duly “waded Bane‘ Nmmam Heaw Duly theaflad BaneL c Heavy Duly “waded am Nu F T H mm: Sui- D-ulipfinll
© 2017 Littelfuse, Inc. • Specifications are subject to change without noticeLittelfuse.com 10
Product
Series Description
Overall Dimensions Contact
Rating
Switching
Voltage
Breakdown
Voltage
Switching
Current
Contact
Resistance, Initial Mating
Actuator
mm (inch) W Vdc Vdc A Ohms
Thread Pitch x L Max. Max. Min. Max. Max.
59060
Stainless Steel Threaded Barrel Sensor, Normally Open M8 x 1.25 Pitch x 36.00 (1.420) 10 200 250 0.5 0.2
57060
Stainless Steel Threaded Barrel Sensor, Normally Open High Voltage M8 x 1.25 Pitch x 36.00 (1.420) 10 300 450 0.5 0.2
Stainless Steel Threaded Barrel Sensor, Changeover M8 x 1.25 Pitch x 36.00 (1.420) 5 175 200 0.25 0.2
Stainless Steel Threaded Barrel Sensor, Normally Closed M8 x 1.25 Pitch x 36.00 (1.420) 5 175 200 0.25 0.2
59065
Threaded Barrel Sensor (Standard), Normally Open (5/16 x 24) Pitch x 38.10 (1.500) 10 200 250 0.5 0.2
57065
Threaded Barrel Sensor (Standard), Normally Open High Voltage (5/16 x 24) Pitch x 38.10 (1.500) 10 300 450 0.5 0.2
Threaded Barrel Sensor (Standard), Changeover (5/16 x 24) Pitch x 38.10 (1.500) 5 175 200 0.25 0.2
Threaded Barrel Sensor (Standard), Normally Closed (5/16 x 24) Pitch x 38.10 (1.500) 5 175 200 0.25 0.2
59070
Threaded Barrel Sensor (Metric), Normally Open M8 x 1.25mm Pitch x 38.10 (1.500) 10 200 250 0.5 0.2
57070
Threaded Barrel Sensor (Metric), Normally Open High Voltage M8 x 1.25mm Pitch x 38.10 (1.500) 10 300 450 0.5 0.2
Threaded Barrel Sensor (Metric), Changeover M8 x 1.25mm Pitch x 38.10 (1.500) 5 175 200 0.25 0.2
Threaded Barrel Sensor (Metric), Normally Closed M8 x 1.25mm Pitch x 38.10 (1.500) 5 175 200 0.25 0.2
59075
Heavy Duty Threaded Barrel, Normally Open M12 x 1mm Pitch x 46.00 (1.810) 10 200 250 0.5 0.2
57075
Heavy Duty Threaded Barrel, Normally Open High Voltage M12 x 1mm Pitch x 46.00 (1.810) 10 300 450 0.5 0.2
Heavy Duty Threaded Barrel, Changeover M12 x 1mm Pitch x 46.00 (1.810) 5 175 200 0.25 0.2
Heavy Duty Threaded Barrel, Normally Closed M12 x 1mm Pitch x 46.00 (1.810) 5 175 200 0.25 0.2
Product
Series Description
Overall Dimensions Contact
Rating
Switching
Voltage
Breakdown
Voltage
Switching
Current
Contact
Resistance, Initial Mating
Actuator
mm (inch) W Vdc Vdc A Ohms
L X W X H Max. Max. Min. Max. Max.
59105
Terminal Flange Mount Sensor, Normally Open 40.17 (1.582) x 19.05 (0.750) x 6.60 (0.260) 10 200 250 0.5 0.2
57105Terminal Flange Mount Sensor, Normally Open High Voltage 40.17 (1.582) x 19.05 (0.750) x 6.60 (0.260) 10 300 450 0.5 0.2
Terminal Flange Mount Sensor, Normally Closed 40.17 (1.582) x 19.05 (0.750) x 6.60 (0.260) 5 175 200 0.25 0.2
59125
Pinned Flange Mount Sensor, Normally Open 28.57 (1.125) x 19.05 (0.750) x 6.35 (0.250) 10 200 250 0.5 0.2
57125Pinned Flange Mount Sensor, Normally Open High Voltage 28.57 (1.125) x 19.05 (0.750) x 6.35 (0.250) 10 300 450 0.5 0.2
Pinned Flange Mount Sensor, Normally Closed 28.57 (1.125) x 19.05 (0.750) x 6.35 (0.250) 5 175 200 0.25 0.2
59135
High-Temp Flange Mount Sensor, Normally Open 28.57 (1.125) x 19.05 (0.750) x 6.35 (0.250) 10 200 250 0.5 0.2
57135
High-Temp Flange Mount Sensor, Normally Open High Voltage 28.57 (1.125) x 19.05 (0.750) x 6.35 (0.250) 10 300 450 0.5 0.2
High-Temp Flange Mount Sensor, Changeover 28.57 (1.125) x 19.05 (0.750) x 6.35 (0.250) 5 175 200 0.25 0.2
High-Temp Flange Mount Sensor, Normally Closed 28.57 (1.125) x 19.05 (0.750) x 6.35 (0.250) 5 175 200 0.25 0.2
59140
Mini Flange Mount Sensor, Normally Open 23.0 (0.906) x 14.00 (0.551) x 6.00 (0.236) 10 200 250 0.5 0.2
57140
Mini Flange Mount Sensor, Normally Open High Voltage 23.0 (0.906) x 14.00 (0.551) x 6.00 (0.236) 10 300 450 0.5 0.2
Mini Flange Mount Sensor, Changeover 23.0 (0.906) x 14.00 (0.551) x 6.00 (0.236) 5 175 200 0.25 0.2
Mini Flange Mount Sensor, Normally Closed 23.0 (0.906) x 14.00 (0.551) x 6.00 (0.236) 5 175 200 0.25 0.2
59141
Mini Flange Mount Sensor, Normally Open 23.0 (0.906) x 14.00 (0.551) x 6.00 (0.236) 10 200 250 0.5 0.2
57140
Mini Flange Mount Sensor, Normally Open High Voltage 23.0 (0.906) x 14.00 (0.551) x 6.00 (0.236) 10 300 450 0.5 0.2
Mini Flange Mount Sensor, Changeover 23.0 (0.906) x 14.00 (0.551) x 6.00 (0.236) 5 175 200 0.25 0.2
Mini Flange Mount Sensor, Normally Closed 23.0 (0.906) x 14.00 (0.551) x 6.00 (0.236) 5 175 200 0.25 0.2
59145
Flange Mount Sensor, Normally Open 28.57 (1.125) x 19.05 (0.750) x 6.35 (0.250) 10 200 250 0.5 0.2
57145
Flange Mount Sensor, Normally Open High Voltage 28.57 (1.125) x 19.05 (0.750) x 6.35 (0.250) 10 300 450 0.5 0.2
Flange Mount Sensor, Changeover 28.57 (1.125) x 19.05 (0.750) x 6.35 (0.250) 5 175 200 0.25 0.2
Flange Mount Sensor, Normally Closed 28.57 (1.125) x 19.05 (0.750) x 6.35 (0.250) 5 175 200 0.25 0.2
59150
Flange Mount Sensor, Normally Open 28.57 (1.125) x 19.05 (0.750) x 6.35 (0.250) 10 200 250 0.5 0.2
57150
Flange Mount Sensor, Normally Open High Voltage 28.57 (1.125) x 19.05 (0.750) x 6.35 (0.250) 10 300 450 0.5 0.2
Flange Mount Sensor, Changeover 28.57 (1.125) x 19.05 (0.750) x 6.35 (0.250) 5 175 200 0.25 0.2
Flange Mount Sensor, Normally Closed 28.57 (1.125) x 19.05 (0.750) x 6.35 (0.250) 5 175 200 0.25 0.2
THREADED BARREL
Designed with a cylindrical package, this sensor is available with English and metric threads.
It may easily be mounted and adjusted using the supplied retaining nuts.
FLANGE/FLAT PACK
This sensor offers a rectangular package that is designed for mounting on a flat surface.
It is suitable for use in a wide range of environments, including high-temperature applications.
Product
Series Description
Overall Dimensions Contact
Rating
Switching
Voltage
Breakdown
Voltage
Switching
Current
Contact
Resistance, Initial
mm (inch) W Vdc Vdc A Ohms
L x W x H Max. Max. Min. Max. Max.
59210 Lever Arm Sensor 24 (0.945) x 23 (0.906) x 10 (0.394) 10 200 250 0.5 0.2
LEVER ARM
This clip frame sensor with a lever arm is ideally suited for paper-path sensing
and security system applications.
REED SENSORS
% Litteltuse” ExnevhxeADnlled \ AnswevxDelweved rum s-riu ”Emma" a aw mstsmn as say , Hum/Mm H-aWuh-age HEISIAZann rum . . “in mum-n Reed Rem S‘L spsmu HEzasmzm H‘ammge uszasmam ' \ Imd_m s-m
© 2017 Littelfuse, Inc. • Specifications are subject to change without noticeLittelfuse.com 11
Product
Series Description
Overall Dimensions Coil Voltage Coil
Resistance Contact Ratings, Switching Contact
Form
Transfer Molded Body External Shield Body
mm (inch) mm (inch) Vdc Vdc Ohms Vdc A W
L x W x H L x W x H Nominal Max. Nominal Max. Max. Max.
HE721A0500
Reed Relay, DIL, SPST-NO 19.05 (.750) x 7.22 (0.284) x 5.50 (0.217) 20.14 (0.793) x 7.62 (0.300) x 5.82 (0.229)
5 12 500
200 0.5 10 Form AHE721A1200 12 31 1000
HE721A2400 24 46 2150
HE721B0500
Reed Relay, DIL, SPST-NC 19.05 (.750) x 7.22 (0.284) x 5.50 (0.217) 20.14 (0.793) x 7.62 (0.300) x 5.82 (0.229)
5 6.5 500
200 0.5 10 Form BHE721B1200 12 14 500
HE721B2400 24 28 2150
HE721C0500
Reed Relay, DIL, SPDT-CO 19.05 (.750) x 7.22 (0.284) x 5.50 (0.217) 20.14 (0.793) x 7.62 (0.300) x 5.82 (0.229)
5 14 200
175 0.25 5 Form CHE721C1200 12 22 500
HE721C2400 24 44 2000
HE721E0500
Reed Relay, DIL, SPDT-CO 19.05 (.750) x 7.22 (0.284) x 5.50 (0.217) 20.14 (0.793) x 7.62 (0.300) x 5.82 (0.229)
5 14 200
175 0.25 5 Form CHE721E1200 12 22 500
HE721E2400 24 44 2000
HE721R0500
Reed Relay, DIL, SPDT-CO 19.05 (.750) x 7.22 (0.284) x 5.50 (0.217) 20.14 (0.793) x 7.62 (0.300) x 5.82 (0.229)
5 14 200
175 0.25 5 Form CHE721R1200 12 22 500
HE721R2400 24 44 2000
HE722A0500
Reed Relay, DIL, DPST-NO 19.05 (.750) x 7.22 (0.284) x 5.50 (0.217) 20.14 (0.793) x 7.62 (0.300) x 5.82 (0.229)
5 12 200
200 0.5 10 Form AHE722A1200 12 22 500
HE722A2400 24 46 2150
HE751A0500
Reed Relay, DIL, SPST-NO,
High Voltage 19.05 (.750) x 7.22 (0.284) x 5.50 (0.217) 20.14 (0.793) x 7.62 (0.300) x 5.82 (0.229)
5 12 500
300 0.5 10 Form AHE751A1200 12 31 1000
HE751A2400 24 46 2150
Product
Series Description
Overall Dimensions Coil Voltage Coil
Resistance Contact Ratings, Switching Contact
Form
Transfer Molded Body External Shield Body
mm (inch) mm (inch) Vdc Vdc Ohms Vdc A W
L x W x H L x W x H Nominal Max. Nominal Max. Max. Max.
HE3321A0400
Reed Relay, SIL, SPST-NO 24.13 (0.950) x 7.00 (0.276) x 7.40 (0.291) 24.90 (0.980) x 7.60 (0.299) x 7.80 (0.307)
5 22 500
200 0.5 10 Form AHE3321A1200 12 22 500
HE3321A2400 24 44 2000
HE3321C0500
Reed Relay, SIL, SPDT-CO 24.13 (0.950) x 7.00 (0.276) x 7.40 (0.291) 24.90 (0.980) x 7.60 (0.299) x 7.80 (0.307)
5 11 125
175 0.25 5 Form CHE3321C1200 12 22 500
HE3321C2400 24 44 2000
HE3351A0500
Reed Relay, SIL, SPST-NO,
High Voltage 24.13 (0.950) x 7.00 (0.276) x 7.40 (0.291) 24.90 (0.980) x 7.60 (0.299) x 7.80 (0.307)
5 14 125
300 0.5 10 Form AHE3351A1200 12 22 500
HE3351A2400 24 44 2000
Product
Series Description
Overall Dimensions Coil Voltage Coil
Resistance Contact Ratings, Switching Contact
Form
Transfer Molded Body External Shield Body
mm (inch) mm (inch) Vdc Vdc Ohms Vdc A W
L x W x H L x W x H Nominal Max. Nominal Max. Max. Max.
HE3621A0500
Reed Relay, SIL, SPST-NO 19.05 (0.750) x 5.08 (0.200) x 7.45 (0.293) 19.70 (0.776) x 5.65 (0.222) x 7.87 (0.310)
5 14 500
200 0.5 10 Form AHE3621A1200 12 22 1000
HE3621A2400 24 31 2150
DUAL-IN-LINE (DIL)
Reed relay products are available in standard dual-in-line packages for mounting
on a printed circuit board or socket.
SINGLE-IN-LINE (SIL)
Reed relay products are available in standard single-in-line packages for mounting
on a printed circuit board or socket.
MINIATURE SINGLE-IN-LINE (SIL)
Reed relay products are available in smaller profile single-in-line packages
for mounting on a printed circuit board or socket.
REED RELAYS
% Littelfuse" Expemsn mm \ Answcv: mums
© 2017 Littelfuse, Inc. • Specifications are subject to change without noticeLittelfuse.com 12
Product
Series Description
Overall Dimensions
Material
Recommended Operating Temp.
mm (inch) ˚C
L x W x H Max.
H-31 AlNiCo Magnet 12.70 (0.500) x 1.60 (0.062) x 1.60 (0.062) AlNiCo-5 450
H-32 AlNiCo Magnet 25.40 (1.000) x 4.80 (0.190) x 4.80 (0.190) AlNiCo-5 450
H-33 AlNiCo Magnet 19.10 (0.750) x 3.20 (0.120) x 3.20 (0.120) AlNiCo-5 450
H-34 AlNiCo Magnet 25.40 (1.000) x 6.35 (0.250) x 6.35 (0.250) AlNiCo-5 450
H-40 Neodymium Magnet 7.62 (0.300) x 3.18 (0.125) x 3.18 (0.125) NdFeB 45H 120
H-41 Neodymium Magnet 19.05 (0.750) x 3.18 (0.125) x 3.18 (0.125) NdFeB 35H 120
H-58 Neodymium Magnet 21.00 (0.827) x 7.00 (0.276) x 4.70 (0.185) NdFeB 35H 120
57105 Actuator for Terminal Flange Mount Sensor 28.57 (1.125) x 19.05 (0.750) x 6.35 (0.250) AlNiCo-5 105
57125 Actuator for Pinned Flange Mount Sensor 28.57 (1.125) x 19.05 (0.750) x 6.35 (0.250) AlNiCo-5 105
57135 Actuator for High-Temp Flange Mount Sensor 28.57 (1.125) x 19.05 (0.750) x 6.35 (0.250) AlNiCo-5 150
57140 Actuator for Mini Flange Mount Sensor 23.00 (0.906) x 14.00 (0.551) x 6.00 (0.236) AlNiCo-5 105
57141 Actuator for Mini Flange Mount Sensor 23.00 (0.906) x 14.00 (0.551) x 6.00 (0.236) AlNiCo-5 105
57142 Actuator for Mini Flange Mount Sensor 23.00 (0.906) x 14.00 (0.551) x 6.00 (0.236) NdFeB 35H 105
57145 Actuator for Flange Mount Sensor 28.57 (1.125) x 19.05 (0.750) x 6.35 (0.250) AlNiCo-5 105
57150 Actuator for Flange Mount Sensor 28.57 (1.125) x 19.05 (0.750) x 6.35 (0.250) AlNiCo-5 105
57045 Actuator for Mini PCB Mount Overmolded 17.78 (0.700) x 3.30 (0.130) x 4.32 (0.170) AlNiCo-5 105
57050 Actuator for PCB Mount Overmolded 22.86 (0.900) x 4.57 (0.180) x 4.57 (0.180) AlNiCo-5 105
Product
Series Description
Overall Dimensions
Material
Recommended Operating Temp.
mm (inch) ˚C
Ø x L Max.
H-35 Neodymium Magnet 6.35 (0.250) x 6.35 (0.250) NdFeB 35H 120
H-48 Neodymium Magnet 4.40 (0.173) x 6.00 (0.236) NdFeB 35SH 150
CM-1 Ceramic Magnet 12.70 (0.500) x 5.08 (0.200) Ceramic-5 250
H-36 AlNiCo Magnet 4.60 (0.182) x 25.40 (1.000) AlNiCo-5 450
H-315 AlNiCo Magnet 3.00 (0.118) x 15.00 (0.590) AlNiCo-5 450
H-420 AlNiCo Magnet 4.00 (0.157) x 20.0 (0.787) AlNiCo-5 450
H-625 AlNiCo Magnet 6.00 (0.236) x 25.0 (0.984) AlNiCo-5 450
57020 Actuator for Mini Firecracker 5.10 (0.201) x 15.24 (0.600) AlNiCo-5 105
57022 Actuator for Firecracker 5.80 (0.228) x 25.40 (1.000) AlNiCo-5 105
57025 Actuator for Firecracker 6.22 (0.245) x 25.40 (1.000) AlNiCo-5 105
57030 Actuator for Long Firecracker 6.22 (0.245) x 38.10 (1.500) AlNiCo-5 105
57040 Actuator for Firecracker with Retaining Ribs 9.5 (0.375) x 31.00 (1.220) NdFeB 35H 105
57060 Actuator for Stainless Threaded Barrel Sensor M8 x 1.25 Pitch x 36.00 (1.420) AlNiCo-5 105
57065 Actuator for Threaded Barrel Sensor (Standard) (5/16 x 24) Pitch x 38.10 (1.500) AlNiCo-5 105
57070 Actuator for Threaded Barrel Sensor (Metric) M8 x 1.25 Pitch x 38.10 (1.500) AlNiCo-5 105
57075 Actuator for Heavy Duty Threaded Barrel M12 x 1.00 Pitch x 46.00 (1.810) Ceramic-2 105
RECTANGULAR
These rectangular bare magnets and packaged actuators are ideally suited for mounting
on a flat surface. They are suitable for use in a wide range of environments, including
high-temperature applications.
CYLINDRICAL
Designed for mounting on a frame, these cylindrical bare magnets and packaged actuators are
appropriate for use in a wide range of environments, including high-temperature applications.
MAGNETIC ACTUATORS
Information furnished is believed to be accurate and reliable. However, users should independently evaluate the suitability of and test each product selected for their own
applications. Littelfuse products are not designed for, and may not be used in, all applications. Read complete Disclaimer Notice at www.littelfuse.com/disclaimer-electronics.
% Litleltuse“ ExpemxeADnllzd \ Anxwux Damn
© 2017 Littelfuse, Inc. • Specifications are subject to change without noticeLittelfuse.com 13
NS
Magnet
User Interface
Ice Dispenser
Reed Sensor
Electronic Control Unit
Frost Sensing
Temp Sensing
LED Light
Appliances like refrigerators, freezers and wine coolers are used to keep food/
beverages cold and extend their useful life. These appliances contain lights to
illuminate the inside compartments when the doors are open. However, the
lights only need to turn on when a door is open. To accomplish this, a proximity
sensor is needed to detect if the appliance door is open or closed.
A reed sensor can be used to detect the position of the door. In refrigerators, a
reed sensor is mounted to the frame of the appliance and a permanent magnet
is mounted to each door. Each reed sensor and magnet pair is positioned so
that the reed switch contacts close only when the door is completely closed.
The position of the reed sensors contacts can be monitored by an electronic
control unit (ECU) within the refrigerators electronics assembly to turn
the interior lights on and off as needed.
Reed sensors are ideal for a variety of position- and proximity-sensing
applications where there is a need to detect the presence of a moving part
in relation to a sensor in a fixed location.
PROXIMITY SENSING USING REED SENSORS—
Refrigerator Door
Figure 1-Reed sensors detect the opening of refrigerator doors
No physical contact required
to operate the switch
• Zero power required for switch
actuation
Electrical contacts are within
a hermetically sealed capsule
that is immune to moisture,
dust and dirt
Wide operating temperature
range adequate for use in cold
temperatures
Overmolded sensors provide
additional protection against
mechanical stresses and
vibration
• Low-cost alternative
to mechanical switch
Features and Benefits:
Suggested Products:
Features and Benefits:
Suggested Products:
FLEX-14 (14 mm reed switch)
MDCG-4 (15 mm reed switch)
MDSR-10 (10 mm reed switch)
59025 (Firecracker reed sensor)
59040 (Firecracker reed sensor)
59140 (Flange mount
reed sensor)
Similar Applications:
Refrigerators/freezers, dish washers, washing machines, rice cookers,
coffee makers, vacuum cleaners and vending machines
Hall effect sensors can be used to detect the movement of a garage door to
stop the motor once the door has reached its open or closed position. Typically,
a system of two Hall effect sensors, each associated with its own permanent
magnet, is used to determine whether the door is completely open, completely
closed or somewhere in between.
One of the magnets is mounted on the chain drive of the garage door opener so
that it is positioned directly next to the Hall effect sensor used to detect a closed
door. The other magnet is positioned so that it moves with the chain and is located
directly next to the other Hall effect sensor when the door is completely open.
Similar to reed sensors, Hall effect sensors are ideal for position or proximity sensing
where there is a need to detect the presence of a moving part in relation to one or
more sensors in fixed locations. They offer extended life and reliability over reed
sensors since there are no electrical contacts that are opened and closed. Common
examples include door- and lid-position sensing in the similar applications listed.
PROXIMITY SENSING USING HALL EFFECT SENSORS—
Garage Door
Receiver
Power Supply
Motor Drive
Hall Effect
Sensor
Electronic Control Board
S
N
N
S
Figure 2-Garage door, Hall effect sensors mounted above garage door opener
No physical contact required
to operate the switch
Wide operating temperature range
adequate for use in hot and cold
temperatures
Hall effect sensor is an integrated
circuit with no mechanical moving
components
Encapsulated sensors provide
additional protection against
environmental/mechanical stresses
and vibration
Reliable operation for millions
of cycles
• Low-cost alternative to mechanical
switches or infrared/optical sensors
55100 (Miniature flange mount
Hall effect sensor)
55140 (Flange mount Hall
effect sensor)
55310 (Flat pack digital Hall
effect sensor)
Similar Applications:
Dishwashers, washing machines, vacuum cleaners, security locks
on doors and vending machines
APPLICATIONS
% Littelfuse’ ExpimscApnlmd \ Answusmllum
© 2017 Littelfuse, Inc. • Specifications are subject to change without noticeLittelfuse.com 14
Reed switch-based sensors are used as highly effective speed sensors in low-cycle-
rateapplications with rates upto a few thousand revolutions per minute (RPM).
For example, in treadmills, a reed sensor is used to detect the speed of the moving
belt. Two permanent magnets are placed on diametrically opposite ends of the belt
pulley, and a reed sensor is mounted to the treadmill frame perpendicular to one
end of the pulley. As the treadmill pulley rotates, the reed sensor detects when
each of the magnets is close to the sensor. The time interval between the detection
of each magnet is used to compute the speed at which the pulley is rotating.
Reed sensors are highly accurate in speed-sensing applications where there
is a rotating part. They are commonly used in fitness equipment where there
is a rotating part with a variable speed.
SPEED SENSING USING REED SENSORS—
Treadmill Pulley
Display Board
Power Supply
Motor Drive
Main Motor Board
User Interface
Reed Sensor
Figure 3-Treadmill pulley
Effective, noncontact solution
used to switch the sensor
Digital output signal is used to
compute speed with high accuracy
Long lifetime and reliable sensing
for millions of operations
Low-cost alternative to infrared/
optical sensors
Overmolded sensors provide
additional protection against
mechanical stresses and vibration
• 59025 (Firecracker)
59065 (Threaded barrel)
59140 (Miniature flange mount)
59150 (Flange mount)
Similar Applications:
Fitness equipment, including treadmill, stationary bicycle and elliptical
cross-trainer
Hall effect sensors make very effective rotary speed sensors. The strengths of
these sensors are their reliability, repeatability, accuracy and high speed. For
example, in a clothes washing machine, a digital or latching Hall effect sensor
can be used to detect a rotating ring magnet to determine the rotating speed
of the drum. Multipole magnets (e.g., 8–40 poles) are typically used as the ring
magnets in these designs. The frequency and resolution of speed are affected
by the number of magnet poles.
Direction, as well as speed, can be measured. The direction signal can be
provided by either quadrature signaling or with the direction encoded in the
pulse width. Quadrature signaling involves two square wave speed signals
where the direction of rotation is determined by the lead vs. lag phase
relationship between the two signals.
Another popular method of detecting speed is to use Hall effect speed sensors
to detect rotating ferrous gear teeth such as in an automotive transmission
speed sensor application. The Hall effect sensor has a back-bias magnet
and detects the variation in magnetic flux density between the gear
tooth and the Hall effect sensor.
SPEED SENSING USING HALL EFFECT SENSORS—
Washing Machine Drum Speed
User InterfaceDisplay Board
Main Motor Board
Power Supply
Main Motor
Hall Effect Sensor
Figure 4-Washing machine drum speed sensor with ring magnet
Digital output signal is used to
compute speed with high accuracy
Long lifetime and reliable sensing
for millions of operations
Effective for high-speed
applications
55140 (Flange mount)
55310 (Flat pack digital)
55505 (Geartooth sensor)
55075 (Geartooth sensor)
• Custom-designed sensor
Similar Applications:
DC motors, vacuum cleaners and wheel speed
SN
Flux Concentration-Tooth Position
Single Low
SN
Flux Concentration-Valley Position
Single High
Figure 5-Geartooth sensing
Features and Benefits:
Suggested Products:
Features and Benefits:
Suggested Products:
APPLICATIONS
% Litleltuse“ ExpemxaADnllzd \ Anxwuxb r,
© 2017 Littelfuse, Inc. • Specifications are subject to change without noticeLittelfuse.com 15
Many types of security alarm systems use a reed switch/sensor attached to the frame
of the door or window. The actuating magnet is attached to the moving door or
window so that when it is opened, the reed sensor detects the moving magnet
and opens/closes its electrical contacts—sending a signal to the alarm system.
Similarly, reed switches can easily be mounted to circuit boards used in smoke
or gas alarm systems. In portable systems, such as gas detectors, the reed switch
is used to activate the system when the handheld detector or reader is placed
in the docking station. In systems with smoke/gas detectors in fixed positions,
the reed switch can be activated with a handheld magnetic wand to put the
detector in test mode.
Reed switches and reed sensors are effective solutions for many types of
security and alarm sensor applications. Examples include detecting the door
and window position, measuring the sump pump water level or activating the
test mode of a smoke detector. Reed relays can be used to activate the alarm
loop in active sensors like motion sensors and smoke detectors.
SECURITY AND ALARM SYSTEMS—
Door and Window Alarms
Alarm Driver
Power Circuit
NS
Magnet Reed
Sensor
Electronic Control Unit
Figure 6-Door alarm system using a reed sensor
No physical contact is required
to operate the switch
Zero power required for
switch actuation
Wide operating temperature range
adequate for use in hot and cold
temperatures
Electrical contacts are within a
hermetically sealed capsule that is
immune to moisture, dust and dirt
Overmolded sensors provide
additional protection against
mechanical stresses
Low-cost alternative to mechanical
switches
• MDSM-10 (10 mm reed switch)
• 59020 (Miniature firecracker)
• 59040 (Press-Fit Firecracker)
• 59140 (Miniature flange mount)
• 59170 (11 mm overmolded
reed switch)
• HE3621A0510 (Miniature SIL
reed relay)
Similar Applications:
Burglar systems, smoke alarms and gas detection systems
Resistive reed ladder networks are used to measure the liquid level in a tank,
which allows for a continuous output signal rather than discrete signals from
single-point level sensors. This continuous level sensor produces a variable
resistance or continuous current/voltage that is related to the position of the
float/magnet assembly. As the liquid level changes, the relative float position
follows, activating the reeds sequentially and producing the associated output
voltage or resistance value. The typical spacing between reed switches is
usually provided in 6.35 mm or 12.7 mm steps.
Littelfuse supplies full assemblies that include stainless steel or plastic
housings. Bare reed switches are also available.
Level sensors incorporating reed switch and resistance technology are
commonly used for measuring continuous liquid levels in the automotive,
marine and industrial markets. The float, which contains a magnet, moves
up or down over the sealed stem containing the reed switches/resistors.
CONTINUOUS LEVEL SENSING—
Industrial Tank Water Level
S
N
S
N
Load
+ -
DC24V
Sensor
Converter
Float
with
Magnet
R16
R15R14
R13
R12R11R4R3
R2
R3R0
S16
S15S14
S13
S12S11
S4
S3S2
S1
S0
White
(Level Signal)
Black
(Ground)
Blue
(Thermistor Single)
Empty Full
R 5 R 4
R 3
R 2
R 1
Figure 7-Resistive reed ladder network for level sensing
Continuous level output signal,
not like a single-point level sensor
Electrical contacts are within a
hermetically sealed capsule that is
immune to moisture, dust and dirt
Sensor housing provides protection
against mechanical stresses
and vibration
Reliable switching for millions
of open/close operations
Wide operating temperature range
adequate for use in hot and cold
temperatures
MDSM-10 (10 mm reed switch)
MDSM-4 (15 mm reed switch)
Custom-designed level sensor
assemblies
Similar Applications:
Fluid-level sensing for: urea in diesel trucks, fuel tanks, HVAC refrigerator
tanks and condensate water tanks
Features and Benefits:
Suggested Products:
Features and Benefits:
Suggested Products:
APPLICATIONS
% Littelfuse’ ExpimscApnlmd \ Answusmllumd
© 2017 Littelfuse, Inc. • Specifications are subject to change without noticeLittelfuse.com 16
When provided with a float magnet, reed sensors can function as fluid-level
sensors. For example, in a dishwasher, a float-type level sensor is used to detect
if the water level inside of the water collection pan has reached the fill limit. The
float sensor consists of a reed switch mounted within a shaft and a permanent
magnet provided within a float housing. The shaft is vertically mounted within
the water collection pan so that the reed switch is positioned at the water fill
limit of the pan. As the water level rises, the magnet within the float travels up
the shaft to the point where it comes into the proximity of the reed switch. The
reed switch senses the presence of the magnet and signals the dishwasher’s
ECU that the water level has reached its fill limit.
Level sensors incorporating reed switch technology are low-cost solutions
for any application where there is a need to detect the amount of liquid in
a tank or pan. They are commonly used in white goods and appliances.
LEVEL SENSING—
Dishwasher Water Level
S
N
ECU
Cold Water Valve Hot Water Valve
User Interface
Reed Sensor
Floating Magnet
Pump Control Temp Sensor
Figure 8-Float sensor detecting water level in a dishwasher
No physical contact required
to operate the switch
Zero power required for switch
actuation
Electrical contacts are within a
hermetically sealed capsule that is
immune to moisture, dust and dirt
Wide operating temperature range
adequate for use in hot and cold
temperatures
Sensor housing provides protection
against mechanical stresses
and vibration
Reliable switching for millions
of open/close operations
59630 (Float sensor)
FLEX-14 (14 mm reed switch)
MDSR-10 (10 mm reed switch)
MACD-14 (14 mm reed switch)
59300 (Level sensor)
Similar Applications:
Dish washers, washing machines, air conditioners, dehumidifiers and
coffee brewers
A flow switch utilizes a reed switch to detect the motion of a valve, paddle
wheel or piston that is fitted with a permanent magnet. For example, in some
tankless water heater units, the flow sensor contains a permanent magnet that
is fixed to a piston that moves when there is water pressure present in the
system. As the water pressure increases, the piston movement brings
the magnet into the proximity of the reed switch. This causes the reed switch
to close and signals the presence of water flow.
A flow sensor utilizes a turbine with an attached magnet that rotates by a fixed
reed switch or Hall effect sensor. The speed at which the turbine rotates is
proportional to the flow rate of the fluid.
Reed sensors are highly effective solutions for flow-sensing applications
where there is a need to detect the presence of liquid or gas flow in a system.
Common uses include water or gas flow in the similar applications listed.
FLOW SWITCH—
Tankless Water Heater
User Interface
Power Circuit
ECU
Outlet
Inlet
Water Flow
Ignition Circuit
Reed Sensor
NSNS
Figure 9-Flow detection in a tankless water heater
No physical contact is required
to operate the switch
Zero power required for switch
actuation
Wide operating temperature range
adequate for use in hot and cold
temperatures
Electrical contacts are within a
hermetically sealed capsule that is
immune to moisture, dust and dirt
Overmolded sensors provide
additional protection against
mechanical stresses
Reliable switching for millions
of open/close operations
• MDSM-4 (15 mm reed switch)
• MLSM-4 (15 mm reed switch)
• MDCG-4 (15 mm reed switch)
• MDSR-10 (10 mm reed switch)
59165 (16 mm overmolded reed switch)
59170 (11 mm overmolded reed switch)
Similar Applications:
Dish washers, washing machines, hot tubs and utility gas meters
Features and Benefits:
Suggested Products:
Features and Benefits:
Suggested Products:
APPLICATIONS
A BROAD & DEEP PORTFOLIO
Littelfuse offers the world’s broadest and deepest portfolio of circuit protection
solutions. Our extensive knowledge and experience in circuit protection
technologies are accessible to our customers around the globe. If you have a
unique circuit protection problem, we have the expertise and resources needed
to develop a solution that delivers exceptional safety and reliability. Our global
research and development teams are constantly working on innovative circuit
protection technologies designed to safeguard the latest products on the market.
Over-Current Protection
Fuses
Resettable positive temperature coefficient (PTC) devices
Over-Voltage Suppression
Gas discharge tubes (GDTs) TVS diode arrays
PLED Series open LED protectors Power Semiconductors
SIDACtor® protection thyristors PulseGuard® ESD Suppressors
Switching thyristors TVS diodes
Varistors
LITTELFUSE OFFERS CIRCUIT PROTECTION
Littelfuse circuit protection products can be used with Hamlin reed switch and sensor products to enhance safety and reliability in various
load-switching applications. We recommend using circuit protection for the following examples of load switching:
Inductive Load Switching – Arc suppression is recommended to maximize the operating life of inductive loads. For DC loads, a diode should
be used. For AC loads, a transient voltage suppression (TVS) diode, a metal oxide varistor (MOV) or a resistor-capacitor (RC) suppression
device may be used. MOV and RC suppression devices should not have too much capacitive inrush current as described below.
Capacitive Load Switching – Capacitance in the load circuit or long cables may cause permanent or intermittent contact sticking.
Contact protection is recommended if the energy stored in the capacitor (E = ½CV2) is greater than 1 µJ. Use a small value resistor
in series with the reed switch for contact protection.
Fuse Blocks
Fuse Clips
Fuse Holders
Fuses
SIDACtor®
Protection Thyristors
TVS
Diode Arrays
PLED
LED Protectors Switching
Thyristors
Varistors
BEYOND SENSING
% Littelfuse” |
GLOBAL FOOTPRINT
At Littelfuse, our mission is to develop innovative circuit protection, power
control and sensing solutions that meet our customers’ unique needs.
This customer-focused philosophy has helped us become the top circuit
protection brand in the world.
Our industry-leading product portfolio includes reliable circuit protection, power
control and sensing products that are designed for a variety of applications. We have
assembled unparalleled expertise and developed a global footprint that puts our
facilities close to our customers and target markets. As our global manufacturing
and R&D teams objectively recommend the best circuit protection, power control or
sensing solution for each customer application, they form partnerships that will lead
to the development of the next generation of advanced products.
TVS Diodes
Resettable
PTC Devices
Gas Discharge
Tubes
PulseGuard®
ESD Suppressors
©2017 Littelfuse, Inc. Information furnished is believed to be accurate and reliable. However, users
should independently evaluate the suitability of and test each product selected for their own
applications. Littelfuse products are not designed for, and may not be used in, all applications.
Read complete Disclaimer Notice at www.littelfuse.com/disclaimer-electronics.
Power
Semiconductors
% Littelfuse“ ExpertiseApplied | Answers Delivered
Littelfuse.com/Magnetic-Sensors-and-Reed-Switches
EC133Nv1017

Products related to this Datasheet

MAGNET 1.125"L X 0.259"W PLASTIC
MAGNET 0.906"L X 0.236"W PLASTIC
MAGNET 1.125"L X 0.259"W PLASTIC
SENSOR REED SW SPST-NO W LEADS
MAGNET 1.125"L X 0.259"W PLASTIC
SENSOR REED SW SPST-NC W LEADS
MAGNET 1.125"L X 0.259"W PLASTIC
SENSOR REED SW SPDT WIRE LEADS
SENSOR REED SW SPST-NC W LEADS
SENSOR REED SW SPST-NO W LEADS
MAGNET 1.125"L X 0.259"W PLASTIC
SENSOR REED SW SPST-NO W LEADS
SENSOR REED SW SPST-NO W LEADS
SENSOR REED SW SPST-NC W LEADS
SENSOR REED SW SPST-NO W LEADS
SENSOR REED SW SPST-NO W LEADS
SENSOR REED SW SPST-NO W LEADS
SENSOR REED SW SPST-NO W LEADS
SENSOR REED SW SPST-NO W LEADS
SENSOR REED SW SPST-NO W LEADS
SENSOR REED SW SPST-NO W LEADS
SENSOR REED SW SPST-NO W LEADS
SENSOR REED SW SPST-NO W LEADS
SENSOR REED SW SPST-NO W LEADS
SENSOR REED SW SPST-NO W LEADS
SENSOR REED SW SPST-NO W LEADS
SENSOR REED SW SPST-NO W LEADS
SENSOR REED SW SPST-NO W LEADS
SENSOR REED SW SPST-NO W LEADS
SENSOR REED SW SPST-NO W LEADS