The HD series of sensors is based on Hall Effect sensor technology, which can
sense a change in target motion from true zero to 20 KHz. The HD series offers dual channel output and, where required directional logic. The output frequency of HD sensors has a square
pulse waveform (digital) that directly relates to the number of turbine blades, gear teeth, etc. that have been
sensed. These pulses, in turn, can be correlated to determine flow rate, RPM, or velocity.
Types of Dual Channel Hall Effect Sensors
These sensors are dual channel versions of our
H series or HM series of sensors and offer two channels of output.
HD sensors based on the HM series require that the target be a magnet, such as magnets embedded in
gear teeth, blade tips, or around a disc. They must be oriented to the direction of the target movement and can be
set to sense both north and south oriented magnets or only north or south respectively. Air gap distances can be as
much as 0.200" to 0.250" away, depending on target shape and magnetic field strength.
HD sensors based on the H series incorporate a magnet within the sensor, enabling them to sense
ferrous metal as well as magnet targets. Maximum air gap sensing distances are typically 0.100" and these sensors can
be optimized to detect fine as well as large pitch targets. As with sensors based upon the HM series, they must be
oriented to the direction of target movement to work effectively.
Standard Features and Specifications
Input Power:
4.7 to 24 VDC regulated, 15 mA maximum @ no load
Reverse polarity protected
Pulse Output Options:
TTL/CMOS (Standard); fan-out of 5 TTL/CMOS loads
Open collector; maximum OFF state voltage 24VDC, maximum ON current 50 mA
Up to 0.250" dependent on target geometry, magnet construction and sensor
construction (for those sensors based on the HM series)
Up to 0.100" dependent on target geometry, magnet construction and sensor
construction (for those based on the H series)
Interconnection Options:
Pigtail with wires or cable
NPT threaded body with wire or cable pigtail for explosion proof environments
Connector per customer specifications
Physical Features:
Operating temperature: -40°C to +105°C
NOTE: units that operate up to +150°C are also available
Storage temperature: -40°C to +150°C
Body material: 300 series stainless steel
Encapsulation: epoxy potting or hermetically sealed, welded construction
Orientation:
`
Alignment of the sensor to target rotation is required for optimal performance,
ensuring proper orientation of the hall effect element to the magnetic field
Approvals:
CE compliant to EMC Directive 89/336/EEC for use in residential, commercial, light
industrial and heavy industrial environments
Warranty:
Unconditional one (1) year warranty if used within specifications
Standard Models
Model Number
Body Styles
Mounting Thread (A)
Thread Length (B)
Overall Length (C)
Connection Type
Type
Output (Pulse Range)
HD-24
A
5/8x18
0.875
3.45
4 conductor pigtail
Dual Pulse
0-5 Vdc
HD-25
B
5/8x18
0.875
3.45
4 conductor pigtail
Dual Pulse
0-5 Vdc
HD-26
C, Type 1
5/8x18
1.75
3.375
4 conductor pigtail
Dual Pulse
0-5 Vdc
HD-27
C, Type 2
5/8x18
1.75
3.75
4 conductor pigtail
Dual Pulse
0-5 Vdc
HD-28
A
3/4x20
0.875
3.45
4 conductor pigtail
Dual Pulse
0-5 Vdc
HD-29
B
3/4x20
0.875
3.45
4 conductor pigtail
Dual Pulse
0-5 Vdc
HD-30
C, Type 1
3/4x20
1.75
3.375
4 conductor pigtail
Dual Pulse
0-5 Vdc
HD-31
C, Type 2
3/4x20
1.75
3.75
4 conductor pigtail
Dual Pulse
0-5 Vdc
HD-32
A
5/8x18
0.875
3.45
5 conductor pigtail
Dual + Direction
0-5 Vdc
HD-33
B
5/8x18
0.875
3.45
5 conductor pigtail
Dual + Direction
0-5 Vdc
HD-34
C, Type 1
5/8x18>
1.75
3.375
5 conductor pigtail
Dual + Direction
0-5 Vdc
HD-35
C, Type 2
5/8x18
1.75
3.75
5 conductor pigtail
Dual + Direction
0-5 Vdc
HD-36
A
3/4x20
0.875
3.45
5 conductor pigtail
Dual + Direction
0-5 Vdc
HD-37
B
3/4x20
0.875
3.45
5 conductor pigtail
Dual + Direction
0-5 Vdc
HD-38
C, Type 1
3/4x20
1.75
3.375
5 conductor pigtail
Dual + Direction
0-5 Vdc
HD-39
C, Type 2
3/4x20
1.75
3.75
5 conductor pigtail
Dual + Direction
0-5 Vdc
Custom Dual Channel Hall Effect Speed Sensors
In addition to the standard models shown above, dual channel hall effect speed sensors are available in custom lengths, diameters, configurations, and mounting threads. Custom operating specifications (resistance, inductance, etc). are available, as well as options such as pigtail leads or NPT threading. Additional sensor customization options
We provide custom sensors on a regular basis and are happy to help develop a solution for your application, or a replacement sensor for an existing application. Please contact our engineering department at eng@motionsensors.com or 252-331-2080 to discuss your application requirements.
