C O M P A N Y ISF-101 Industrial Sensor Fundamentals Instructor Rob Smith.

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ISF-101 Industrial Sensor Fundamentals

Instructor

Rob Smith

C O M P A N Y

C O M P A N Y

Objectives of ST120

• With the fast paced industrial world looking for ways to manufacture products better, faster and more economically, it is important to be knowledgeable of sensor technologies.

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Continued• This class is designed to give you a

fundamental understanding and working knowledge of different sensor technologies. We will achieve this through the study of sensor technologies, terminology explanations, lab exercises and application examples.

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What Is a Sensor

• According to Merriam-Webster's dictionary, it’s a device that responds to a physical stimulus and transmits a resulting impulse.

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Advantages of Electronic Sensors

•Non-contacting•Wear and tear is kept to a minimum•A must for fragile equipment•Odd shapes (not a problem)

•Reliable•Last a long time (Solid State)•A mechanical switch has a definite life span•Few maintenance problems•Longer/better reliability

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Continued

•Variety of sensing Capabilities•Speed•Almost any size sensor•Almost any size object (* getting smaller)

•Variety of Design Features•Quick disconnect•Short circuit protection•Diagnostic features (alarm output, check input, indicator lights)

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Types of Sensors

Photoelectric•Through-Beam•Retro-Reflective•Diffuse Reflective•Fiber Optics•Color Mark•Specialized

Proximity•Inductive•Capacitive

Miscellaneous•Ultrasonic•Reed•Variable Reluctance•Laser•Specialty Sensors

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TYPES OF SENSORS

Inductive Proximity

Capacitive Proximity

Photoelectric

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Chapter 1

Proximity Sensors

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Proximity Sensors

• Variations– Inductive– Capacitive

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Inductive Proximity SensorInductive Proximity Sensor

Counting teethin gears

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Basic Construction and Basic Construction and Circuit Make-up.Circuit Make-up.

1. Sensor Head2. Oscillator Circuit3. Detector Circuit4. Switching Circuit (output)

DETECTOR

OUTPUT

SENSOR

TARGET

OSCILLATOR

OPERATING PRINCIPLEOPERATING PRINCIPLE


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1. Sensor Head

DETECTOR

OUTPUT

SENSOR

TARGET

OSCILLATOR



The front end of the sensor consists of a wire-wound ferrite iron core. This is the physical part of the sensor that produces the actual sensing field.

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Metal Object

Metal Object

Primary Magnetic FieldPrimary Magnetic FieldEddy CurrentEddy Current

OscillatorOscillator DetectingCircuit

DetectingCircuit

SensorSensor

The Sensing Field

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2. Oscillator Circuit

DETECTOR

OUTPUT

SENSOR

TARGET

OSCILLATOR



The oscillator is the circuit that powers the wire winding in the coreand its “power” is monitored by the detector circuit for resulting detection.

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Sensing a Moving TargetSensing a Moving Target

On On Off On On

Moving ObjectMoving Object

Amplitude of oscillationAmplitude of oscillation

Off

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3. Detector Circuit

DETECTOR

OUTPUT

SENSOR

TARGET

OSCILLATOR



The Detector Circuit converts theamplitude of the oscillating signal to aDC RMS level from which the ON and OFF thresholds are used to trigger the output circuit.

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Sensor Turn-On/Turn-Off ProcessSensor Turn-On/Turn-Off Process

Observed Voltage Level in the Detection Circuit

Output switching thresholds

ON

Off

ON

Off

Hysterises

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4. Switching Circuit (Output)

DETECTOR

OUTPUT

SENSOR

TARGET

OSCILLATOR



The Output Circuit handles the actualswitching and control of the output.

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Sensing DistanceSensing Distance

Sensing ZoneSensing Zone


The Sensing ZoneThe Sensing Zone

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Shielded and Unshielded “Shielded” and “Unshielded” are two terms

used to describe these sensors. The basic difference in these two types arrive from their mechanical construction.

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Shielded and Unshielded The ferrite core/winding construction

varies between the two styles, as does the shielding.

Cores

Shielding

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Shielded and Unshielded In general, these two construction styles

yield slightly different sensing performances. In summary, the unshielded style will provide approximately twice the sensing distances with an inherent drawback of specific mounting and installations requirements.

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ShieldedShielded

18mm

30mm dia.

Un-ShieldedUn-Shielded

10mm

30mm dia.

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Target ConsiderationTarget Consideration

1. Target Characteristics•Composition•Size and Thickness•Shape

2. Speed of Target3. Target spacing or interval4. Frequency Response of the sensor

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Choosing the right Inductive SensorChoosing the right Inductive Sensor

BadTarget too small for sensor

GoodTarget and sensor size comparable

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Method of Detection Inductive Shielded Inductive Unshielded

Configuration Designed for flush mounting

in metal. Available in

cylindrical and limit switch

sensor shapes.

Requires clearance

around sensing end to

prevent false signals from

surrounding metal.

Available in cylindrical,

limit switch and small

block, flat rectangular

sensor shapes.

Advantages Detect ferrous (iron, mild

steel, stainless steel) and

non-ferrous (brass, copper,

aluminum) metals. Allows

flush mounting to prevent

impact damage to the

sensor. Color and surface

conditions of the target do

not affect sensing. Most

cost-effective option where

appropriate.

Detect ferrous (iron, mild

steel, stainless steel) and

non-ferrous (brass,

copper, aluminum) metals.

Longer sensing distance

than shielded sensors.

Color and surface

conditions of the target do

not affect sensing.

Disadvantages Reduced sensing distance.

Useable only to 0.4inch

maximum.

Sensor is not protected

from accidental impact

damage. Usable only to

0.7 inch maximum.

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Sensing Metal Lid on ContainersSensing Metal Lid on Containers

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PNPBlue-0V

Black-Output

Brown24vdc

PowerSupply

+Common

Sensor WiringSensor Wiring

European Standard Older Color Configuration

Brown 12 to 24vdc Red 12 to 24vdc

Blue 0vdc Black 0vdc

Black sensor output White sensor output

NPN Blue-0V

Black-Output

Brown24vdc

PowerSupply

+

Common

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Sensor Electronics

Base

Collector

Emitter

Black-Output

Brown 24vdcBlue-0V

Common

PowerSupply

+

PNP Electronic Circuit Diagram

Sourcing Sensor

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Black-Output

Brown 24vdc

Blue-0V

Common

PowerSupply

+

Sensor Electronics

Base

Collector

Em

itter

NPN Electronic Circuit Diagram

Sinking Sensor

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Inductive Proximity Sensor – Lab Exercise

Hook up the sensor and verify its operation by sensing the Din rail on your demo board. (The control relay should activate when the output turns on).

Lay the sensor on it’s side, directly on the din rail. Does the output activate? _______

Why?_______________________________________

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Continued

Test the sensitivity of the various metal objects:

1. Using the paper from your note pad. Place one piece of paper on the test units. Press the sensor nose down on the paper.

2. Continue adding paper until the sensor no longer senses the test object.

3. Record the number of sheets, before detection was lost.

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Continued

Recordings

1. Steel Bolt_____

2. Aluminum_____

3. Copper (penny)_____

4. Brass Fitting _____Bonus: Can non-metallic objects be sensed? _____

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Specifications – Catalog ReviewE2A 3-Wire DC Series P. F-44

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Capacitive Proximity Sensors

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A Capacitive Proximity sensor is similar to an inductive sensor in that it has a Oscillator, Detector and Output circuit. It differs in that it uses a plate shaped Electrode instead of a wire-wound core. In operation, it forms an electrostatic capacitive field formed between it and the the sensors ground. (In practice the supply line is in effect the ground.)

Sensing CircuitSensing CircuitElectrode PlateElectrode Plate

SENSORSENSOR

Oscillator Circuit Detector Circuit OutputCircuit

Ground

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When there is no target object in the area of the sensor the field that is formed will be stable.

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When a target object nears the sensor its positive and negative charges (normally neutralized) separate. The negative charges in the target are attracted towards the electrode, and its positive charges towards ground. This “influence” increases the electrostatic capacitance of the electrode which increases its coupling with ground. This provides increased amplitude in the oscillator circuit, which is in turn used to switch the output in the detection circuit.

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Capacitive Sensing RangeCapacitive Sensing Range

•Affects sensor setting distance

Objects Size & Shape Objects Size & Shape

Milk

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Dielectric Constants

The measure, or unit of Dielectric Constant, is the ability of a material to concentrate electrical flux. Its numerical value is specified as the ratio of flux in the material verses the flux in air or vacuum. The dielectric constant of air or vacuum is 1 – since it is the reference.

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Materials Constants

Acetone 19.5

Acrylic Resin 2.7-4.5

Air 1.000264

Alcohol 25.8

Ammonia 15-25

Aniline 6.9

Aqueous Solutions 50-80

Bakelite 3.6

Benzene 2.3

Cable Sealing Compound 2.5

Carbon Dioxide 1.000985

Carbon Tetrachloride 2.2

Celluloid 3.0

Cement Powder 4.0

Cereal 3-5

Chlorine Liquid 2.0

Ebonite 2.7-2.9

Epoxy Resin 2.5-6

Ethanol 24

Ethylene Glycol 38.7

Fired Ash 1.5-1.7

Flour 1.5-1.7

Freon R22 & 502 (liquid) 6.11

Gasoline 2.2

Materials Constants

Glass 3.7-10

Glycerin 47

Hard Paper 4.5

Marble 8.0-8.5

Melamine Resin 4.7-10.2

Mica 5.7-6.7

Nitrobenzene 36

Nylon 4-5

Oil Saturated Paper 4.0

Paraffin 1.9-2.5

Paper 1.6-2.6

Perspex 3.2-3.5

Petroleum 2.0-2.2

Phenol Resin 4-12

Polyacetal 3.6-3.7

Polyamide 5.0

Polyester Resin 2.8-8.1

Polyethylene 2.3

Polypropylene 2.0-2.3

Polystyrene 3.0

Polyvinyl Chloride Resin 2.8-3.1

Porcelain 4.4-7

Powdered Milk 3.5-4

Press Board 2.5

C O M P A N Y Materials Constants

Quartz Glass 3.7

Rubber 2.5-35

Salt 6.0

Sand 3-5

Shellac 2.5-4.7

Shell Lime 1.2

Silicon Varnish 2.8-3.3

Soybean Oil 2.9-3.5

Styrene Resin 2.3-3.4

Sugar 3.0

Sulpher 3.4

Teflon 2.0

Toluene 2.3

Transformer Oil 2.2

Turpentine Oil 2.2

Urea Resin 5-8

Vaseline 2.2-2.9

Water 80

Wood (dry) 2-7

Wood (wet) 10-30

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Mutual InterferenceMutual Interference

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Capacitive Method of Detection

Configuration Requires clearance around sensing end

to prevent false signals from

surrounding mounting materials.

Available in cylindrical and flat

rectangular sensor shapes.

Advantages Detects plastic, glass, liquids, leather

and wood as well as metals. Can be

used to detect materials inside non-

metallic containers.

Disadvantages Sensor is not protected from accidental

impact damage. Usable to 0.9inch

maximum.

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Application SampleApplication Sample

High Water Limits

Low Water Limits

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Capacitive Proximity Sensor – Lab Exercise

In this exercise we will be using the Capacitive Proximity style sensor in a very typical application use. To detect the fluid level of a liquid. Follow the outlined steps to complete the lab.

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Materials needed: Sensor, power supply, plastic container and water

• Wire the sensor to the power supply, and apply power.

• Position the face against the plastic bottle at locations above the water line and adjust the sensitivity (potentiometer). The LED indicator will be on, back the adjustment off so that the indicator goes off.

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Continued

• Move the sensor down along the side of the bottle to a location with fluid in front of the unit. At this point the LED will again turn on.

• Move the sensor up and down along the side, checking to see if the sensor activates at the water level. If not readjust until sensor works properly.

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Specifications – Catalog ReviewE2K-C Series P. F-130

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Chapter 2

Photoelectric Sensors

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• Variations– Through-beam– Retro-reflective– Diffuse reflective– Fiber optics– Color mark– Specialized

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Through Beam Sensors

Through BeamThrough Beam

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Principle of Operation

Through-beam sensors consist of two parts, an emitter (the light source) and a receiver (the detector). A beam of light links the two - establishing a sensing area.

Receiver Emitter

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Principle of Operation

The target to be detected passes through the beam, breaking the link between the emitter and the receiver. When this occurs, the object has been sensed.

Receiver Emitter

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Amplifier Unit

Output Circuit

Light Detecting

Circuit

Light Emitting Element

Principles of OperationPrinciples of Operation

Moving Object

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Amplifier Unit

Output Circuit

Light Detecting

Circuit

Light Emitting Element

Principles of OperationPrinciples of Operation

Moving Object

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As the method of operation is by breaking the beam, the sensor is not affected by the target’s color, texture or glossiness. However, the size of the object must be taken into consideration. Some through-beam sensors have sensitivity adjustments to allow different sizes to be detected.

Receiver Emitter

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Mode of Operation

Light On – The output of the sensor operates when the beam is uninterrupted.

Receiver Emitter

ON

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Mode of Operation

Dark On – The output of the sensor operates when the beam is interrupted.

Receiver Emitter

ON

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Installation

• Sensing distance• Alignment• Mutual interference

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Retroreflective

Retro-Reflective

Mirror

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Principles of Operation

Unlike the through-beam sensor, the retroreflective sensor has the emitter and receiver in one body. The light beam is established by the use of a reflector, returning the light from the transmitter back to the receiver.

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Retro-ReflectiveRetro-Reflective

Retro-Reflective

Mirror

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Retro-Reflective

Mirror

Movingobject

Like the through beam sensor, the object is detected by breaking the path of the beam. The retroreflective sensor has an advantage over the through beam type, in that the unit requires wiring of only one component.

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Since the target is detected by breaking the beam, the operation is not affected by the object color or shape.

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Just like the through beam, the sensor can operate in Light On and Dark On mode.

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Possible Problems

Even though color and shape do not affect this sensor type, the sheen or glossiness of the item may have an adverse affect. If the object is extremely shiny, or highly reflective, it could reflect more light back to the receiver than the reflector does on its own. It this case the object could/would pass by undetected. As a commonly found issue, there is a solution for these applications.

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Polarized Retroreflective

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OperationInstead of thinking of light as one uniform beam, simplified it can be split into two components that make up the beam. These components are horizontal and vertical light waves.

Horizontal

Vertical

Beam

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Polarized Retro-Reflective SensorPolarized Retro-Reflective Sensor

Horizontal Light Returned

900

Vertical Light Out 900

Reflector

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PolarizingFilter

Reflector

Shiny Object

Reflector

Sensor

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Polarized Retroreflective – Lab Exercise

Materials needed:

1. Sensor and sensor controller.(E3S-AR81)

2. Plexiglas squares ¼” and ½” thick.

3. Orange reflector

4. Red and white reflector

5. Shinny aluminum

C O M P A N Y

• Hook up the sensor to the sensor controller. DO NOT CONNECT THE BLACK SIGNAL WIRE! This is a PNP sensor not compatible with the controller. Therefore, for this exercise we will be utilizing the indicators LED’s for diagnostics.

• Place the sensor in the clamp and set the sensitivity to its maximum. Have your lab partner hold the reflector and back it away until you find the maximum distance.

What is the maximum stable distance? __________

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• Space the sensor and reflector approximately 5-8 inches apart and adjust the sensitivity so that a clear ½” thick piece of Plexiglas can be detected.

• Repeat process for the ¼” Plexiglas.

Can this object type be detected with stable sensor operation? _______

• Try detecting the following objects.

Material Success Y / N

Orange Reflector

Red/White Reflector

Shiny Aluminum Foil

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Diffuse Reflective

C O M P A N Y

The Diffuse sensor incorporates the Emitter and the Receiver in the same body, much like the Retro-reflective sensors.

C O M P A N Y

Unlike the retroreflective sensor, there is no separate reflector in use to return light back to the receiver. Instead, this sensor type relies on light reflection coming off of the object itself. This configuration has the advantage one-piece wiring, and no reflector. This is especially useful in those applications where there may be access to only one side, or mounting problems exist.

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Background SuppressionIn some applications the background behind the object being sensed can have adverse effects on the sensor's ability to detect the object.

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Diffuse Reflective – Lab Exercise

• Hook up the sensor and verify its operation by placing your hand in front of the sensor to activate the output.

• Set the sensitivity of the sensor to its maximum setting. Position a piece of the colored paper in front of the sensor and slowly back it away to find the maximum sensing distance. Repeat this process for each test piece and document your results.

C O M P A N Y

Recordings

Color and Sheen Maximum Distance (inches)

White (Matte)

White (Glossy)

Green (Matte)

Green (Glossy)

Blue (Matte)

Blue (Glossy)

Black (Matte)

Red (Matte)

Red (Glossy)

C O M P A N Y

• Could this sensor be used to differentiate colors (COLOR MARK SENSOR) ?________

Why____________________________________________________________________________________

• Try to detect the black foam material. Is it detectable?_______

Why___________________________________________________________________________________

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For Your Information

If all of these sensors work on the principal of light, then why does the ambient light affect the sensor?

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Modulation

Modulating an LED means turning it on and off at a set frequency. This is generally done at high frequency with short bursts of voltage. By applying power in this manor the circuit is able to generate a very high intensity light at a certain spectrum. Because the LED is not on continuously it does not suffer from the adverse affects of heat.

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Continued

The secret of a modulated system’s superior performance is that the sensors receiving circuit is tuned to the emitters specific light spectrum. Since the receiver is set to respond specifically to this spectrum, the effects of ambient light are virtually ignored. This is similar to a radio receiver which tunes solidly to one station, while ignoring all other radio waves that are present.

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Comparison Chart 1

Target Thru-beam Retroreflective Diffuse

Dark opaque Good Good Poor

Shiny opaque Good Poor Good

Clear Poor Good Poor

Multi colored opaque

Good Maybe Poor

Light opaque Good Maybe Poor

Translucent Maybe Good Maybe

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Comparison Chart 2

Target Thru-beam Retroreflective Diffuse

Range (Feet) Long Medium Short

Detection Good Fair Fair/Poor

Repeatability Excellent Fair Fair

Environmental Resist Excellent Fair Fair

Installation Cost High Medium Low

Adjustment Time Low Low Medium

Versatility Medium Medium Low

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Specifications – Catalog ReviewE3Z Series P. B-122

C O M P A N Y

Fiber Optics

C O M P A N Y

Fiber optic photoelectric sensors consist of two parts, the amplifier and the sensing head. The amplifier contains the emitter (light source) and the receiver (detector) along with their associated electronics. The fiber optic cable is the means used to transfer the light to the sensing head.

C O M P A N Y

Why Fiber Optics•Allows for use of sensors in small areas (flexible).

•Can be used in Hazardous areas.

•Ability to see small objects (0.5mm or .002” diameter with addition of a lens).

• Can be used in high and low temperatures.

C O M P A N Y

600

Light Reflecting Diode Fiber Optic Cable

Detecting IC Chips on Film Sheet

C O M P A N Y

TransmissionLight is transmitted down the cable by repeatedly reflecting the light off the boundary between the fiber core and the sheath, until it reaches the end of the fiber where it is disbursed through specific lensing.

Sheath

Core

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Fiber Heads

The three types of fiber heads.

Through beam, Diffuse, and Retroreflective (not very common). They operate on the same principal as of the standard photoelectric sensors.

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Through Beam

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Diffuse

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Types of Fibers

Standard fiber

This fiber consist of a single core that is protected by a plastic sheath.

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Types of FibersConcentric fiber

The Concentric fiber consists of a core fiber which is used to conduct light from the transmitter. The smaller surrounding fibers carry light back to the receiver. This allows for greater sensing accuracy and allows for installation of only one piece.

C O M P A N Y

Specialized Photoelectric Sensors

•Focal point sensor (A-400)

•Spot Sensor (A-300)

•Color Mark Sensor (A-346, A-322)

•Luster Sensor (A-216)

•Clear Material Sensor (A-186, 196, 202)

C O M P A N Y

Focal Point Sensor

Focal point sensors are a reflective style sensor that have a narrow beam width and are designed to detect objects at the reflection point and nowhere else. They are used to detect objects at a specific distance. The light source and receiver accepts the strong beam of regular reflection which enables the sensor to detect small and dark objects

Omron Page A-400

C O M P A N Y

Focal Point Sensor

Emitter Receiver

Sensing Area

Emitter Receiver

C O M P A N Y

Spot Sensor

The spot sensor sometimes refereed to as a convergent beam sensors. With this sensor the light source is positioned perpendicular to the object and the receiver is set at an acute angle to detect only diffuse light from the object. It avoids receiving directly reflected light. This sensor style detects differences in object surface condition, small objects, or objects in a pinpoint.

Omron Page A-300

E3C-VM35R

C O M P A N Y

Spot Sensor

Emitter Receiver

Sensing Area

C O M P A N Y

Spot Sensor

Emitter Receiver Emitter Receiver

C O M P A N Y

Color Mark Sensor

These sensors are designed to detect marks of varying color contrast on a common surface. They have a similar light source and receiver arrangement as spot sensors, but they have increased sensitivity to changes in color. They can detect a color mark by contrast to non-marked area rather than by direct color measurement.

Omron Page A-346E3M-V

C O M P A N Y

Color Mark Sensor

Emitter Receiver

Sensing Area

Emitter Receiver

C O M P A N Y

Color Mark SensorThere are three types of light sources each gives a different range of sense.

• Incandescent lamps: Best for wide range of color conditions. (Shorter life than LED).

• Green LED: Green LED’s provide longer life than incandescent and provide sensitivity for a wider range of colors than red light sources.

• Red LED: Red LED’s respond to a limited number of color combinations, but give longer sensing distances.

•RGB: Combination of Red, Green, and Blue LED’s. Largest selection of colors.

C O M P A N Y

Luster Sensor

Unlike all the other sensors that detect the presence of an object, the luster sensor looks at the sheen (glossiness) of an object.

Omron Page A-216

C O M P A N Y

Clear Material Sensor

Detection of clear material such as plastic and film could traditionally be done using a polarized retroreflective sensor. This works but may not always be reliable. A specialized sensor was created to allow for the detection of clear materials.

Omron Page A-186,196,202

C O M P A N Y

Chapter 3

Ultrasonic Sensors

C O M P A N Y

Ultrasonic Sensors

C O M P A N Y

Operation

Ultrasonic sensors utilize high frequency sound energy (above the audible range - ultrasound) to measure distance or detect objects. These devices transmit a burst of ultrasound energy, then wait for a return echo. By precisely calculating the time distance can be determined.

Electro Corp Cat Page 94

C O M P A N Y

Targets should be perpendicular to the face of the sensor.

C O M P A N Y

Roll Diameters: The axis of the roll should be perpendicular to the face of the sensor

C O M P A N Y

Fluids: Should be stable and or static.

C O M P A N Y

Solids: Must be dense enough to reflect sound energy

C O M P A N Y

Chapter 4

Other common sensing technologies

C O M P A N Y

Reed Sensors

Reed sensors, or more commonly referred to as switches. Reed switches are commonly used on cylinders to indicate end of stroke position. They consist of two thin metal reeds which open and close when a magnet passes by. This design gives a very fast action(for mechanical switches) and produces a maintained signal as long as the magnet is present.

C O M P A N Y

Physical Construction

The reeds are always mounted in a nitrogen filled glass tube which may be enclosed in another housing for protection against breakage. The clean nitrogen atmosphere assures long contact life for greater reliability. The contact arrangement is always single-pole, single-throw and can be either N.O. or N.C.

C O M P A N Y

Physical Construction

C O M P A N Y

Magnetic Sensors

Two styles:

• Variable Reluctance (Passive)

• Magneto Resistive (Active)

C O M P A N Y

VRSVariable reluctance sensors are completely self powered sensing devices that do not require an external voltage source to operate. They are generally used to provide speed sensing data for feedback and control of rotary motion mechanical components, or devices. (Tachometers)

C O M P A N Y

VRSThe output of a VRS produces an AC voltage signal. This signal varies in amplitude and wave shape as the speed of the monitored device changes. The most commonly used with a metal gear. Other appropriate targets are bolt heads, keys, keyways, magnets, and holes in metal disks.

C O M P A N Y

VRSA permanent magnet is the heart of the VRS sensor and establishes a fixed magnetic field. An output is generated by the changing strength of this field caused by the approach and departure of a ferrous metal target. This disturbance in the magnetic field varies the reluctance, or the “or the resistance of flow” in the magnetic field which in turn dynamically changes the strength of the field. This change in the magnetic field strength induces a current into a coil winding which is attached to the output terminals of the sensor.

C O M P A N Y

VRS

C O M P A N Y

Magneto Resistive SensorsMagneto Resistive sensors provide a square wave digital output driven by the same type of alternating – Presence and absence target presentation as that of the VRS. This sensor style does require a voltage source for operation, which is typically specified 5 – 15 VDC.

C O M P A N Y

Magneto Resistive SensorsMagneto Resistive devices contain a highly sensitive bridge circuit which reacts to the movement of ferromagnetic gear teeth. This imbalance of the bridge circuit is amplified to create the output signal. Because these are power devices, there is virtually no low speed limitations with this style sensor.

C O M P A N Y

Questions?

Thank You!

C O M P A N Y ISF-101 Industrial Sensor Fundamentals Instructor Rob Smith.

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