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Banner Products
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Early Photoelectric Sensors
Early sensors used anincandescent bulb as
the light source
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Wavelength (nanometers)
400
Ultraviolet Visible Light Infrared
Sunlight
500 600 700 800 900 1000
Red
LEDGreenLEDInfrared
LED
Phototransistor
ResponsePhotocellResponse
BlueLED
Optical Device Response
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Emitter
Receiver
Pulse Modulated Light
A Modulated (Pulsed)Light Source
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onoff
Advantages of LEDs
Long Life
Vibration Resistant
Ability to Modulate
Solid State Reliability
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Photoelectric Keys to Success:
Excess Gain
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Light
on Receiver Element
ReceiversThreshold
Excess Gain (E.G.) =
Excess Gain Formula
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Guidelines ForExcess Gain Values
1.5X
5X
10X
50X
Clean Air
Slightly Dirty
Moderately Dirty
Very Dirty
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Excess Gain Chart
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Photoelectric Keys To Success:
Excess Gain Contrast
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Light Level at Receiver
in Light Condition
Light Level at Receiver
in DarkCondition
Contrast =
Contrast
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1.2 : 1orLess
Unreliable for traditional photoelectrics,consider D12E or D11E
1.2 : 1to
2 : 1
Poor contrast, consider sensors with
ac-coupled amplification
2 : 1
to3 : 1
Low contrast, sensing environment must
remain clean and all other sensingvariables must remain stable
Contrast Values And CorrespondingGuidelines
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Contrast Values And CorrespondingGuidelines
3 : 1to
10 : 1
Good contrast, minor sensing systemvariables will not affect sensingreliability
10 : 1
orGreater
Excellent contrast, sensing shouldremain reliable as long as the sensingsystem has enough excess gain foroperation
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Photoelectric Keys To Success:
Excess Gain
Contrast
Effective Beam
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Effective Beam OfOpposed Mode Sensors
Receiver
Radiation Pattern
EffectiveBeam
Field-of-View
Emitter
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Effective Beam ForRetroreflective Mode Sensor
Retroreflective
Target
Retroreflective Sensor
Radiation Patternand Field-of-View
Effective Beam
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Effective Beam is the
Sensor Radiation Pattern
Effective Beam
Object
Effective Beam Diffuse Sensing
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Effective BeamConvergent Sensing
Sensing
Depth-of-Field
Area of
Maximum Signal
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Photoelectric Keys To Success:
Excess Gain
Contrast
Effective Beam
Sensing Modes
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Opposed Mode
Advantages
Most Reliable Sensing Mode
Highest Excess Gain and Longest Range
Great Contrast When Sensing an OpaqueObject
Concerns
May not Work with Transparent or
Translucent Objects
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Emitter
Object
Receiver
Opposed Sensing Mode
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Excess Gain Chart
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Typical Opposed Mode Beam Pattern
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Highest Optical Gain!
Opposed Mode Without Apertures
Proper Alignment
Radiation Pattern
Receiver
Field of View
Effective Beam
Emitter
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Narrow Beam Pattern
Opposed Mode With Apertures
Proper Alignment
Radiation Pattern
Receiver
Field-of-View
EffectiveBeam
Emitter
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Less Tolerant Of Misalignment
Opposed Mode Without Apertures
Misalignment
Radiation Pattern
Receiver
Field of View
Effective Beam
Emitter
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Aperture Examples
WORLD-BEAM
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Improperly Placed
Bottle Cap Breaks Beam
Receiver Emitter
Aperture Application Example
Eff ti B With
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Receiver/Emitterwith Large Lens
Emitter/Receiverwith Small Lens
Emitter/Receiverwith Aperture
Effective Beamis Cone-shaped Receiver/Emitter
with Large Lens
Effective Beam WithUnequal Lens Diameters
Light Ope ate s Da k Ope ate
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Light Operate vs. Dark OperateOpposed Mode System
Light Operate Dark Operate
Output Energized whenBeam is Unblocked, theReceiver Sees Light
Output Energized whenBeam is Blocked, theReceiver Sees Dark
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Retroreflective Mode
Advantages
Good Excess Gain and Range
Great Contrast when Sensing an OpaqueObject
Only Need to Apply Power to One Side
Concerns
Not as Good as Opposed Mode in a Dirty
Environment
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QS18
Retro Target
Object
Retroreflective Sensing Mode
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Retroreflective Sensors with Separate Emitter
and Receiver Lenses Have a Blind Spot at VeryClose Range
Retro Target
Retro Sensor
EmitterLens
ReceiverLens
Target Lens
Retroreflective Blind Spot
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Excess Gain Chart
Typical Beam Pattern
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Typical Beam PatternRetroreflective Sensors
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Extended Retroreflective Range
The Range of Most Retroreflective Sensors may be
Extended by using Additional Retroreflective Target Area
BeamSize
Retroreflective
Sensor
Cluster of BRT-3Retroreflectors
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Boxes with ShinyVinyl Wrap
Retroreflective
Target
RetroreflectiveSensor
Conveyor
Reflected Light
SkewAngle
>10
Use Of Skew Angle To Avoid Proxing
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Polarized Light
Emitted Light isLinearly Polarized
Shiny Object
Retroreflector
Light Reflected 90 byCorner-Cube Reflector willPass thru Receive Filter
Light Reflected in Phase
by Shiny Object andBlocked by Receiver Filter
Retroreflector
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Excess Gain Chart
Light Operate vs Dark Operate
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Light Operate vs. Dark OperateFor A Retroreflective Mode Sensor
Dark Operate
The output is energized whenan object blocks the light from
reaching the retroreflective target.The sensor sees dark
Light Operate
The output is energizedwhen the beam is unblocked,
the sensor sees light
Retro
Target
Opaque
Object
Retro
Target
Retro
Sensor
Opaque
Object
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Move Target Up-Down, Left-Right
Retroreflective Mode Alignment
Retro Target
Up
Down
Left
Right
QS18LV
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Diffuse Sensing Modes
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Diffuse Mode
Advantages
Moderate Excess Gain and Range
Good Contrast
No Need for Power or Reflectoron Opposite Side
Concerns
Contrast and Sensing Distance Depends
on Object Color and Reflectivity
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Object EmittedLight
ReceivedLight
Diffuse Sensing Mode
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Effective Beam
Effective Beam is the
Sensor Radiation Pattern
Object
Effective Beam Diffuse Sensing
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Relative Reflectivity Table
Material Reflectivity (%) Excess Gain Reqd
Kodak white
test card
White paper
Masking tape
Beer foam
Clear plastic
90%
80%
75%
70%
40%
1
1.1
1.2
1.3
2.3
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Relative Reflectivity Table
Black anodized
aluminum
Rough wood pallet
Natural aluminum,
unfinished
Stainless Steel,
micro finish
50%
20%
140%
400%
1.8
4.5
0.6
0.2
Material Reflectivity (%) Excess Gain Reqd
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For Materials with Shiny or Glossy Surfaces, theReflectivity Figure Represents the Maximum Light
Return, with the Sensor Beam Exactly Perpendicularto Material Surface
Relative Reflectivity Table
Black neoprene
Black rubber tire
Clear plastic bottle
4%
1.5%
40%
22.5
60
2.3
Material Reflectivity (%) Excess Gain Reqd
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Excess Gain Chart
Typical Beam Pattern
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Typical Beam PatternDiffuse Mode Sensors
Diffuse Sensing Of Shiny Surface
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Diffuse Sensing Of Shiny SurfaceSensor Parallel For Reliable Detection
UnreliableReliable
Divergent Proximity
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Divergent ProximitySensing Mode
Object
QS18
Minimum Distance To Reflective Background
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Minimum Distance To Reflective BackgroundSurface For A Diffuse Mode Sensor
3X min.
X
X = Distance From Sensor to Web
3X = Minimum Distance from Web to Floor
Floor
Web Travel
QS18VP6D
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Fixed-FieldSensing Mode
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E
R2
Lenses
Object A Object B
Emitter
Receivers
Sensing Field
R1
Object is Sensed if Amount
of Light at R1 is Greater Than
the Amount of Light at R2
Fixed-Field Sensing Mode
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Fill Level Application
Fixed-Field
Sensor
Filler
Coffee
Can
Direction
Emitter
Receiver
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Light OperateThe output is energized when lightis reflected directly from an objectsurface. The sensor sees light.
Dark OperateThe output is energized when no objectis present in front of the sensor to returnthe emitted light. The sensor sees dark.
ReflectiveObject
For a Proximity Mode Sensor (diffuse, divergent,
convergent, and background suppression)
Light Operate vs Dark Operate
ReflectiveObject
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ConvergentSensing Mode
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Convergent Mode
Advantages
Better Excess Gain and Contrast thanDiffuse Mode Sensing
No Need for Power or Reflector on
Opposite Side Concerns
Limited Range and Sensing Angle is MoreCritical on Shiny Objects
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Convergent Beam Sensing Mode
Sensing
Depth-of-Field
Focus
Object
QS18
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Excess Gain Chart
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Beam Pattern
Convergent Beam
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Bottle Counting
Convergent
Sensor
ProductFlow
QS18
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SM312CV
Direction
Register
Mark
web
Label
ConvergentSpot
NOTE SENSOR
ANGLE
Register MarkDetection
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Fiber Optic Sensing Mode
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Fiber Optic Sensing Mode
Custom Assemblies for Special Mounting
Needs
Hazardous Locations
Moves Light Signal in/out of Remote
Locations Withstands Shock and Vibration
Inherent Noise Immunity
Restricted Sensing Locations Smaller Size than Self-Contained Sensors
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Stainless SteelFerrule (Typical) Stainless SteelInterlock Sheathing
IndividualGlass Strands
PolishedSurface
OpticalEpoxy
Glass Fiber Optic Construction
ki i
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Packing Fraction
IndividualGlass Strand
PackingFraction
~ 30% Signal Loss
Typical IndividualFib O i A bl
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Used for Opposed, Mechanical Convergent,
Specular and Long Range Diffuse Sensing Modes
Fiber Optic Assembly
Typical BifurcatedFib O ti A bl
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Used for Diffuse and Retroreflective Sensing
Two Branches are Randomly Mixed into One
Fiber Optic Assembly
Gl Fib O ti Ad t
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Glass Fiber Optic Advantages
Extreme Temperature Applications -600F,
900 F all Metal Designs
Standard Temperatures -200 F to 480 F,-40 F to 220 F PVC, Phenolic Parts 400 F Maximum
Corrosive/Wet Environments
Profile Matching of Parts Possible
Logic Functions Possible with Multi-Branched Models
Fib O ti C
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Fiber Optic Concerns
System Cost
Loss of Excess Gain
Gl Fib O ti N t
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Glass Fiber Optic Notes
Repeated Flexing Causes Fiber Breakage
Radiation will Darken Glass
Fibers can not be Modified for Length
Pl ti Fib O ti C t ti
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Plastic Fiber Optic Construction
PolishedSurface
Bare
MonofilamentOptical Fiber
Epoxy
DummyInsert
PolyethyleneJacketed
Optical Fiber
Nickel Plated BrassThreaded Tip
Pl ti Fib O ti Ad t
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Plastic Fiber Optic Advantages
Less Cost than Glass Fibers
Flexible-Coiled Models
Less Signal Attenuation than Glass
Field Modifiable Length
Cutters Supplied with Each Cable Assembly
Plastic Fibe Optic Notes
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Plastic Fiber Optic Notes
IR Light not Transmitted well Through Plastic
Visible LEDs are Used
Visible LEDs Have Less Optical Powerthan Infrared LEDs
Single Filament on Relatively Large Scale
Glass .05 mmversusPlastic .25 mm, .50 mm, 1.0 mm,or .1.5 mm
Bend Radius of Cable Affects Transmission
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Application Considerations
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Application Considerations
Environmental
Mechanical
Mode
Interface
Logic
Response Time
Environmental Considerations
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Environmental Considerations
Temperature
Shock & Vibration
Chemicals or Radiation
Electrical Noise
Hazardous Gases, Liquids, Filings
Dirt, Dust, Smoke, Spray, Washdown
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Hazardous Area Sensing
Types Of Sensors For Hazardous Areas
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Types Of Sensors For Hazardous Areas
Explosion Proof
Intrinsically Safe
Namur
NEMA Ratings
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NEMA Ratings
NEMA 4 Hosedown
Stream of water 1 inch in diameter, at a rateof 65 gallons per minute, at a range of 12feet, for a minimum 5 minutes
NEMA 4x Hosedown and Corrosion Same test as NEMA 4, and shall not rust when
subjected to a salt spray (fog) test for 200hours
NEMA Ratings
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NEMA Ratings
NEMA 6 Occasional Submersion
Submerge six feet under water for 30minutes (includes NEMA 4)
NEMA 6P Prolonged Submersion
Submerge Six feet under water for 24hours (includes NEMA 4X)
Mechanical Considerations
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Mechanical Considerations
Size
Angle
Wiring Runs
Accessibility
Indicators
Sensing Mode Considerations
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Sensing Mode Considerations
Opacity of the Target
Effective Beam Size
Range
Contrast
Interfacing Considerations
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Interfacing Considerations
Voltage to Power Sensor
Voltage Required for Load
Current Draw of Load
Response Time of Load
Digital or Analog
Current Sinking Output
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Current Sinking Output
Switching Element
(NPN) Transistor
+V dc
output
dccommon
To+V dc
Todc Common
Load
Current Sourcing Output
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Current Sourcing Output
Switching Element
(PNP) Transistor
+V dc
output
dccommon
Load
To+V dc
Todc Common
Example Of A Solid-StateBipolar Output
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Bipolar Output
+
-
Out
+V dc
dc Common
Current SourcingOutput
Current SinkingOutput
Out
SensingCircuit
Example Of Bi-Modal Output
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Example Of Bi Modal Output
Current Sourcing (PNP) Configuration
SourcingOutputON
Sinking
OutputOFF
36V
Load Output 10-30V dcSupply Voltage
Blue Brown
Current
SenseAndOutputSelect
Load Circuit
Example Of Solid-StateComplementary Output
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Complementary Output
-
NO
+V dc
dc Common
Normally ClosedOutput
Normally OpenOutput
NC
Sensing
Circuit
+
Logic Considerations
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Logic Considerations
L/O or D/O
Single Sensor or Multiple Sensors
Timing Delays or Holds
Response Time of Load
Common Timing Logic
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Common Timing Logic
One-Shot
ON-Delay
OFF-Delay
One-Shot Logic
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One Shot Logic
Signal
Output
ON-Delay Logic
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ON Delay Logic
Delay
Input
Output
OFF-Delay Logic
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OFF Delay Logic
HoldHold
Input
Output
Response Time Considerations
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Response Time Considerations
Width of Part
Linear Velocity
Tr = W/V
Tr = Required Response Time
W = Width of Part
V = Speed of Part
Calculating Response TimeFor Small Objects
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For Small Objects
Width of Object Diameter of Effective Beam
Speed of the Object
Required Response Time
Equals
Application Example
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.55 Inch Diameter Pin
.5 Inch Diameter Effective Beam
Application Example
Emitter Receiver
EffectiveBeam
100"/Sec.
Pin
Application Example
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Application Example
Required Sensor Response Time is Eased
by Use of Apertures
Emitter Receiver
.1" EffectiveBeam
100"/sec.
Pin
Aperture Aperture
Required Sensor Response Time
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Time of Dark Condition
Pin Diameter Effective Beam Diameter
Speed of the Pin through the Beam
Equals
Equals
.55" - .1"100 in./sec.
.45 inch
100 in./sec.4.5 Milliseconds= =
equ ed Se so espo se e
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MeasurementArrays
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Arrays
Scan Analysis Modes
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y
FBB First Beam Blocked
LBB Last Beam Blocked
TBB Total Beams Blocked
CBB Contiguous Beams Blocked
FBM First Beam Made
TBM Last Beam Made
CBM Total Beams Made
ALL All Data
VHSVehicle Separation
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LogProfiling
Hole-In-Web Application
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pp
Edge-Guiding
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g g
Paint Booth ProfilingApplications
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pp
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Laser Photoelectrics
Family
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WORLD-BEAMQS18
WORLD-BEAMQ12
WORLD-BEAM
QS30
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LT7
LT3
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Ultrasonic Sensors
U GAGE T30U
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U-GAGE T30U
Pump-In Application (switch #1 off)
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Sensor
Flow
Pump Control
Initial Level
1 Initial Tank Level Outputs are INACTIVE
11
Low Level (Far Limit)
2 Level Drops Below Far Limit Outputs ACTIVE
2
High Level (Near Limit)
3 Level Rises Above Near Limit Outputs DEACTIVATE
3
1
2
NOTE: If no echo is received by the sensor,the target is assumed to be beyond
the far window limit.
Pump-Out Application (switch #1 on)
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Flow
Pump Control
Sensor
1 Initial Tank Level Outputs are INACTIVE
Initial Level1
2 Level Rises Above Near Limit Outputs ACTIVE
High Level (Near Limit)2
1
3 Level Drops Below Far Limit Outputs DEACTIVATE
Low Level (Far Limit)
2
1
3
NOTE: If no echo is received by the sensor,the target is assumed to be beyond the far
window limit.
QT50U
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QT50U App
lication
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Pallet Load
QT50U Universal Supply VoltageTarget Applications
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Tank Level Detection or Measurement
Q45UR
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Q45UR Has Automatic Windowing
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Follows Same HOLD, CLICK, CLICK,
Routine as other Banner Products
1. Set Window Size with DIP Switches
2. Set up Good Condition
3. Hold, Click, Click to TEACH the
Nominal Good Distance
Good Bad Bad
2 mm
1, 2, 3, or 4 mm Windows
Q45UR And M18
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Web Thickness
M18
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Roll Diameter
S18U Applications
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Minimum and Maximum Limitswith Analog Model to Control
a Clear Object Loop
Retrosonic Sensing Presence ofObjects Regardless of Part Shapeor Orientation
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QS18 Ultrasonic
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