754 Photoelectric Sensors - İmtek · 754 Photoelectric Sensors Photoelectric ... glass, metal,...

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TECHNICAL GUIDE 754 Photoelectric Sensors Photoelectric Sensors Safety Light Curtains Ultrasonic Sensors Proximity Sensors Pressure Sensors PLCs Counters Barcode Readers Vision Systems Displacement Sensors Optical Micrometers Communication Method Microscope Laser Markers Enclosure Rating www.keyence.com 754 1. Outline A photoelectric sensor emits a light beam (visible or infrared) from its light-emitting element. A reflective- type photoelectric sensor is used to detect the light beam reflected from the target. A thrubeam type sensor is used to measure the change in light quantity caused by the target crossing the optical axis. Reflective type Light-receiving element Light-emitting element Reflected light beam Target Thrubeam type Transmitter Light-emitting element Light beam Target Light beam is intercepted Receiver Light-receiving element Features • Non-contact detection Non-contact detection eliminates damage either to the target or sensor head, ensuring long service life and maintenance-free operation. • Detection of targets of virtually any material Detection is based on the quantity of light received, or the change in the quantity of reflected light. This method allows detection of diverse targets such as glass, metal, plastics, wood, and liquid. • Long-detecting distance The reflective-type photoelectric sensor has a detecting distance of up to 2 m 6.6', the thrubeam type has a detecting distance of up to 40 m 131.2', and the retro-reflective type has a detecting distance of up to 50 m 164'. • High response speed The photoelectric sensor is capable of a response speed as high as 20 µs. • Color differentiation possible The sensor has the ability to detect light from an object based on the reflectivity of its color, thus permitting color detection and differentiation. • Highly accurate detection A unique optical system and a precision electronic circuit allows highly accurate positioning and detection of minute objects. Light beam emission methods Pulse emission KEYENCE photoelectric sensors employ the pulse light beam emission method and use an LED or a semiconductor laser as the light source. This allows the sensor to emit, at intervals, a strong light beam of preset pulse duration, enabling a long-detecting distance, and stable detection with minimal interference from external light. Time Light-emitting quantity Continuous emission This allows the sensor to continuously emit a preset quantity of light. However, This method does not provide a long-detecting distance, due to weak light beams resulting from the limited current level of the light-emitting element, and is also vulnerable to extraneous light. Its response speed is also higher than that of the pulse beam emission method. Time Light-emitting quantity

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1. OutlineA photoelectric sensor emits a light beam (visible or infrared) from its light-emitting element. A reflective-type photoelectric sensor is used to detect the light beam reflected from the target. A thrubeam type sensor is used to measure the change in light quantity caused by the target crossing the optical axis.

Reflective type

Light-receiving element

Light-emitting element

Reflected light beam

Target

Thrubeam typeTransmitter

Light-emitting elementLight beam

Target

Light beam is intercepted

Receiver

Light-receiving element

Features• Non-contact detection

Non-contact detection eliminates damage either to the target or sensor head, ensuring long service life and maintenance-free operation.

• Detection of targets of virtually any materialDetection is based on the quantity of light received, or the change in the quantity of reflected light. This method allows detection of diverse targets such as glass, metal, plastics, wood, and liquid.

• Long-detecting distanceThe reflective-type photoelectric sensor has a detecting distance of up to 2 m 6.6', the thrubeam type has a detecting distance of up to 40 m 131.2', and the retro-reflective type has a detecting distance of up to 50 m 164'.

• High response speedThe photoelectric sensor is capable of a response speed as high as 20 µs.

• Color differentiation possibleThe sensor has the ability to detect light from an object based on the reflectivity of its color, thus permitting color detection and differentiation.

• Highly accurate detectionA unique optical system and a precision electronic circuit allows highly accurate positioning and detection of minute objects.

Light beam emission methodsPulse emissionKEYENCE photoelectric sensors employ the pulse light beam emission method and use an LED or a semiconductor laser as the light source. This allows the sensor to emit, at intervals, a strong light beam of preset pulse duration, enabling a long-detecting distance, and stable detection with minimal interference from external light.

Time

Ligh

t-em

ittin

g qu

antit

y

Continuous emissionThis allows the sensor to continuously emit a preset quantity of light. However, This method does not provide a long-detecting distance, due to weak light beams resulting from the limited current level of the light-emitting element, and is also vulnerable to extraneous light. Its response speed is also higher than that of the pulse beam emission method.

Time

Ligh

t-em

ittin

g qu

antit

y

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Detection configuration and features

Type Detection configuration Features

Thrubeam

Transmitter

Target

Receiver

Detection occurs when the target crosses the optical axis between transmitter and receiver.• Long-detecting distance• Stable detecting position• Opaque objects detectable regardless of shape, color

or material• Powerful beam

Retro-reflective

Target Reflector

Detection occurs when the target crosses the optical axis between sensor head and reflector.• Reflector allows installation in a limited space• Simple wiring• Longer detecting distance than the diffuse-reflective sensor type• Easily-adjustable optical axis• Opaque objects detectable regardless of shape, color,

or material

Diffuse-reflective

TargetDetection occurs when the light beam, emitted to the target, is reflected by the target and received.• Space-saving (requires installation of sensor unit only)• Adjustment of optical axis not required• Reflective transparent objects detectable• Color differentiation possible

Focused-beam reflective Target

Detection occurs when the beam spot, emitted to the target, is reflected by the target and received.• Minute objects detectable• Target markings detectable• Detection possible through narrow openings between machines• Visible beam spot

Small-spot definite-reflective

Target The transmitting and receiving portions are constructed at an angle, allowing detection within the limited area where the optical axes intersect.• Effect of target background is minimal• Low hysteresis• Slight height differences are detectable• Visible beam spot

Fixed-distance TargetDetects the target at a specific distance according to the angle of the reflected light beam.• Unaffected by highly reflective targets or backgrounds• Stable detection of materials with varying reflectance and color• Highly accurate detection of minute objects• Visible beam spot

Luster recognition Target When the light beam hits a target, the beam reflects differently according to the luster of the target. The sensor detects the difference in luster based on how the beam reflects (specular or diffusive).• On-line detection is possible.• Detection is not affected by target color.• Transparent targets can be detected.

Optical passage confirmation

Target

The detecting area is formed by uniform parallel beams. When a target passes through this area, the received light quantity changes. Detection is performed based only on this change.• Minute targets can be detected.• Only moving targets are detected.• Detection is less affected by dirt or dust on the lens.

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2. GlossaryGlossary

Term Configuration Definition

Detecting distance

Thrubeam typeTransmitter

Detecting distance

Receiver

The maximum distance from the transmitter to the receiver that permits the receiver to stably receive a light beam emitted from the transmitter (thrubeam type) or reflected from the reflector (retro-reflective type).

Retro-reflective type

Detecting distance

Reflector

Reflective types (diffuse, small-spot definite, focused- beam, narrow-beam, distance-specific)

Detecting distance

Standard targetThe maximum distance from the sensor head to a standard target that permits the sensor head to stably detect a light beam reflected from the standard target.

Hysteresis

Reset distance

Detecting distance

HysteresisON OFF

• For a reflective-type photoelectric sensor, the difference between the reset distance and the detecting distance using a standard target.

• Hysteresis of photoelectric sensor is represented as a ratio to the detecting distance (X% of detecting distance).

• The reset distance refers to the distance from the light-receiving surface of a sensor head to the point at which sensor resets for subsequent detection.

Response time

Light received

Light shielded

Controloutput

ON

OFF

t= Response timet t

The minimum period of time required for a sensor to detect the presence of a light beam and output an ON signal, or to detect the absence of a light beam and output an OFF signal.

LIGHT-ON

Thrubeam and retro-reflective types

TransmitterON (without target)

Receiver

An operating mode that allows the sensor head to output an ON signal when the prescribed light quantity, or more, is detected.Reflective type

ON (with target)Sensor head

DARK-ON

Thrubeam and retro-reflective types

Transmitter ReceiverON (with target)

An operating mode that allows the sensor head to output an ON signal when the prescribed light quantity, or more, is blocked by the target.

Reflective type

Sensor headON (without target)

Ambient lightTransmitter Receiver

White mat paper

Incandescentlamp

Illuminance meter

The maximum amount of ambient light received by the light-receiving surface of the sensor that allows a sensor to function normally.

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Self-diagnostic functionWhen optical misalignment or dirt or dust on the lens decreases the received light quantity, it results in unstable detection. An alarm output or indicator light is activated to inform the operator of a need for maintenance.

Misaligned optical axis

Dirt or dust accumulation on lens

FS01 and PS01 SeriesWhen the received light quantity exceeds the detection level but does not exceed the stable operation level “31 times continuously” or “for 8 seconds continuously”, the stability output is activated.Reset: When the stability output is activated, clean the front surface of the sensor head or realign the optical axis, so that the stable operation indicator (green LED) lights again. The stability output is reset when detection occurs with the stable operation indicator (green LED)

turned on.

Operation chart

3 311 2Stable operation

level

Detection level

Controloutput

ONOFF

Stability output

“8 seconds”

The received light quantity does not exceed the stable operation level 31 times continuously.

The received light quantity does not exceed the stable operation level 8 seconds continuously.

Note: When several units are connected, the stability outputs of all the units are output from the main unit based on OR logic.

PZ2 SeriesThe stable operation indicator (green LED) of each sensor turns OFF when the received light quantity exceeds 70% or drops below 150% of the operating level. While the stable operation indicator is OFF, detection is unstable and erroneous detection may occur.

0.7

1

1.5Relative level ofreceived light quantity

OFF

ON

OFF

ON

Operation indicator

Stable operationindicator

Stable operation level

Operation level

Stable light-interruptionlevel

3. Light Source TypesKEYENCE photoelectric sensors use a red LED, green LED, infrared LED, red laser diode or infrared laser diode as the light source. These light sources have the following features. Therefore, by properly choosing a light source according to your application, excellent detection results can be obtained.

Reference graph: Light source and wavelength

1.0

0.8

0.6

0.4

0.2

0500 550 600 650 700 750 800 850 900 950 1,000 1,050

Wavelength data (typ.)

Wavelength (nm)

Rel

ativ

e ra

diat

ion

pow

er 2 3 4 51

1 Green LED2 Red LED3 Red semiconductor laser

Type Features Model

Red LED

Visible beam spotColor mark detection (Differentiating white, red or yellow color from black, blue or green color)

FS01, FS2-60/62/65, PS-206/47/49, FS-V, PZ-V/M, PZ2, PZ-101, PZ-G, PX

Infrared LED

Allows long-distance detection because light beam is powerful.Does not damage unexposed film.

PX, PS, PQ, PG, PW, PZ-G

Green LED

Visible beam spotSuited for detection of subtle differences because light attenuation factor is high.Color mark detection (Differentiating white, yellow or orange color from black, green, red or blue color)

FS-V21G/V22G,FS-T1G, FS2-60G

Laser diode (Red, infrared)

Allows minute targets to be detected due to an extremely small beam spot.Allows long-distance detection with focused light beam.Red laser diode and infrared laser diode are available, and have the same features as red LED and infrared LED, respectively.

LV, GV

4 Infrared semiconductor laser5 Infrared LED

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4. Fiber Photoelectric SensorsThe photoelectric sensor incorporates optical fibers and can be installed in areas of limited space.

1. Operating principle and types• Operating principle

The optical fiber consists of the core and the cladding, which have different refractive indexes. The light beam travels through the core by repeatedly bouncing off the wall of the cladding. The light beam, having passed through the fiber without any loss in light quantity, is dispersed at an angle of approximately 60° and emitted to the target.

LED

Optical fiberCore (high refractive index)

Cladding (low refractive index)

Approx. 60°

• Optical fiber types Plastic-fiberThe core of the plastic-fiber consists of one or more acrylic-resin fibers 0.25 to 1 mm 0.01" to 0.04" in diameter, encased in a polyethylene sheath. Plastic fibers are light, cost-effective, and flexible and are used for the majority of optical fiber photoelectric sensors.

Glass-fiberThe glass-fiber consists of 10 to 100 µm 0.39 to 3.94 Mil diameter glass fibers encased in stainless steel tubing, allowing it to be used at high operating temperatures (350°C (662°F) max.).

2. Features• Versatile installation

A flexible optical fiber is employed for easy installation in areas such as small spaces between machines.

• Detection of small objectsThe light-emitting surface of the sensor head is extremely compact for stable detection of small objects.

• Stable operation in harsh environmentThe optical fibers are unaffected by electrical noise as no electric current flows through them.

• Heat-resistantThe heat-resistant fiber unit allows detection in a high temperature environment (350ºC (662ºF) max).

3. ShapeThe optical fiber sensors are divided into two categories: thrubeam and reflective. The thrubeam type comprises a transmitter and a receiver. The reflective type, which is a single unit, is available in 3 types: parallel, coaxial, and separate, according to the shape of the cross-section of the optical fiber.

Type Description

Parallel

Generally used for plastic fibers.

CoaxialHigh-precision type, consisting of a core (transmitter) and surrounding area (receiver). The operating position can remain the same regardless of the direction from which the target enters the detecting area.

Separate This type, containing several 10 µm-0.39 Mil glass fibers in diameter, has separate areas for the transmitter and receiver.

4. Bend radiusExcessively bent optical fiber will result in loss of light, causing reduced detection accuracy.KEYENCE fibers are available with extra-small bending radius.

• Retention of light quantity vs. bend radius (typ.)

100

90

80

70

60

50

0

100

90

80

70

60

50

0 5 10 15 20 25 30 1 2 3 4 5 6

Bend radius (mm inch) Bend radius (mm inch)

FU-6F plastic fiber (standard type)

FU-67 plastic fiber (tough-flex type)

Ret

entio

n (%

)

Ret

entio

n (%

)

1.20" 0.39" 0.59" 0.79"0.98"1.18" 0.04"0.08" 0.12"0.16 0.20"0.24"

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80

60

40

20

0 2 4 6 8 10 2 4 6 8 100

160

120

80

40

FU-6F reflective type FU-7F thrubeam type

With FS2-60G

Fiber length (m feet)Fiber length (m feet)

Det

ectin

g di

stan

ce (

mm

inch

)

Det

ectin

g di

stan

ce (

mm

inch

)

With FS2-60With FS2-60

With FS2-60G

6.6' 13.1' 19.7' 26.2' 32.8'

3.15"

2.36"

1.57"

0.79"

6.30"

4.72"

3.15"

1.57"

6.6' 13.1' 19.7' 26.2' 32.8'

Air

Liquid

Air

Liquid

No liquid is contained. Liquid is contained.

YellowRed

0 200 400 600 800 1,000

950

945

941

938

927

735

720

540

370

305

149

123

121

108

100

90

White

Red

Yellowish orange

Orange

Yellow

Silver

Gold

Reddish purple

Purple

Yellowish green

Green

Greenish blue

Bluish green

Dark blue

Black

Blue

Received light level

White

Yellow

Silver

Yellowish green

Yellowish orange

Gold

Orange

Green

Greenish blue

Bluish green

Red

Blue

Reddish purple

Dark blue

Purple

Black

Received light level0 100 200 300 400 500 600

508

506

483

455

401

319

317

143

140

116

112

92

90

78

64

60

5. Fiber length and detecting distanceThe detecting distance of a fiber photoelectric sensor varies depending on the fiber length.

6. Liquid level detection fiber unitsDetecting principle of liquid level detection fiber unit

Liquid immersion type (FU-93)When the fiber unit tip is present in the air, the emitted light is entirely reflected by the fiber unit’s PFA sheath and returns back to the receiver because the refraction factor between the PFA sheath and air is large. On the other hand, when the fiber unit tip is immersed in liquid, most of the emitted light is radiated into the liquid and does not return back to the receiver because the refraction factor between the PFA sheath and liquid is small. The FU-93 detects presence or absence of liquid by using the above characteristics.

• Fiber length vs. detecting distance (typ.)

Tube-mountable type (FU-95)When the tube, to which the fiber unit is mounted, contains no liquid, the emitted light is reflected by the inside wall of the tube and returns back to the receiver because the refraction factor between the tube and air is large. On the other hand, when the tube contains liquid, most of the emitted light is radiated into the liquid and does not return back to the receiver because the refraction factor between the tube and liquid is small. The FU-95 detects presence or absence of liquid by using the above characteristics.

7. Color differentiation chartsFor color differentiation, choose a light source producing a distinct difference in the reflectance of the 2 colors to be differentiated (i.e. select a light source that allows the sensitivity setting positions, corresponding to the 2 colors being discriminated, to be as far apart as possible).The charts below give reference data for color differentiation. Detection is, however, affected by the surface condition and luminosity of the target. Confirm the sensitivity difference of the colors to be differentiated using the actual target.

Red LED Amplifier: FS-T1, FS-V1 Fiber unit: FU-6F Setting distance: 15 mm 0.59"

Green LED Amplifier: FS-T1G Fiber unit: FU-6F Setting distance: 5 mm 0.02"

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• The received light level is a value which numerically expresses the light quantity received by the sensor.• The previous chart contains sample colors. Note that they may differ slightly from those used in obtaining the data

due to print quality.

Intermediate value =

Received light quantity with white target + Received light quantity with red target

2

=508 + 116

2= 312

The sensor stably detects the light being received.

Excess gain of white color = 508

x 100 = 162%312

The sensor stably detects the light being interrupted.Therefore, the FS-T1G can stably differentiate red and white targets.

116Excess gain of red color = x 100 = 37%

312

How to read the chart

The chart shows the difference in received light quantity between the FS-T1 and FS-V1 (red LED) and the FS-T1G (green LED) manufactured by KEYENCE.• Guide to color differentiation

When the received light level of one colors is 110% or more of the intermediate value of the two colors to be differentiated, the sensor stably detects the light being received. When the received light level is 90% or less, the sensor stably detects the light being interrupted.

Example: To differentiate red and whiteFrom the chart, the FS-T1 (red LED) shows similar received light levels for white and red; while the FS-T1G shows some difference. To calculate the excess gain of color differentiation, perform the following calculation:

5. Reading Characteristic Charts

Operating distance vs. detecting distance Receiver excess gain vs. detecting distance

Ex. PZ-41(P)/41L(P)

400 800600200

40

20

0

20

40

100 300 500 700

X

Y

0

Distance X (mm inch)

Operating level (600 mm)

Operating level (300 mm)

Dis

tanc

e Y

(m

m in

ch)

1.57"

0.79"

0.79"

1.57"

3.94" 11.81"

11.81"

19.69"

23.62"

27.56"

This graph shows the points, at various set distances, where the reflective-type sensor can detect a standard target traveling perpendicular to the optical axis when the maximum detecting distance is provided. The graph is used to confirm the detecting distance of an object travelling perpendicular to the optical axis.

Ex. PZ-51(P)/51L(P)

100

10

1

1.5

0

Detecting distance (mm inch)

StableOperating level

Exc

ess

gain

Operating level

2,000 8,000 10,000 12,000 14,000 16,0004,000 6,00078.74" 236.22" 393.70" 551.18"

This graph shows the level of excess gain at various set distances, under optimal sensitivity conditions, and serves to indicate the sensor setting range at specific distances. In the chart, the PZ-51(P) is provided with a range (excess gain) 5 times greater than the rated stable operating level and a detecting distance of7 m 23.0'. The greater the excess gain, the less disturbance the sensor receives from external conditions.

Parallel displacement of optical axis Detecting distance vs. object size

Ex. PZ-51(P)/51L(P)

0

500

400

300

200

100

500

400

300

200

100

1,000 3,000 5,000 7,000 9,0002,000 4,000 6,000 8,000 10,000

X

Y

Distance X (mm inch)

Dis

tanc

e Y

(m

m)

Operating levelStable operating level

19.69"

19.69"

15.75"

15.75"

11.81"

11.81"

7.87"

7.87"

3.94"

3.94"78.74" 157.48" 236.22" 314.96" 393.70"

This graph shows the points, at various distances, where a receiver (reflector, if retro-reflective type) perpendicular to the optical axis detects a light beam emitted from a transmitter. It is used to confirm the displacement of the receiver (or reflector) to its optical axis.

Ex. PZ-41(P)/41L(P)

0

1000

800

600

400

200

50 100 150 200

a

aWhitematpaper

One side of target a (mm inch)

Stable operating level is calibrated so that the detecting distance is 600 mm for 200 mm square target.

Stable operating levelOperating level

Dis

tanc

e Y

(m

m in

ch)

39.37"

31.50"

23.62"

23.62"15.75"

7.87"

7.87"

7.87"5.91"3.94"1.97"

This graph shows the effect of the size of a target (white mat paper) on the detecting distance. The area covered by the light beam can be verified for a given detecting distance. It is used to determine target size.

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Detecting area Optical axis angle

Ex. FS2-65, FU-4F

0.08"ø0.02"ø0.02"

ø0.01"ø0.01"

0.16" 0.24"

0.08"

0.04"

0.04"

0

2

1

1

2

X

Y

4 6

ø0.001"

ø0.004"ø 0.03 ø0.1

0.08"

ø0.001"

ø0.004"

2

ø 0.03 ø0.1

ø 0.3

ø 0.5

Target: copper wire

Dia.

Distance X (mm inch)

Dis

tanc

e Y

(m

m in

ch)

This graph shows the relationship between target diameter (copper wire) and detecting area. For example, according to the graph a copper wire of 0.1 mm 0.04" in diameter can be detected within the shaded area.

Ex. PZ-51/51L(P)

Y

40 20 0 4020

θ

0

Stableoperatinglevel

Operatinglevel

Operating angle (θ°)

Dis

tanc

e Y

(m

m in

ch)

10,000

5,000

393.70"

196.85"

This graph shows the permissible angle of the receiver to the optical axis of the transmitted beam for a thrubeam type sensor.

Interference area Hysteresis

Ex. FS2-60, FU-65

X

Y

2

4

6

6420

Distance X (mm inch)

Interference area

Dis

tanc

e Y

(m

m in

ch)

Operating area

Whi

te m

at p

aper

0.24"

0.24"

0.16"

0.16"

0.08"

0.08"

Photoelectric sensors placed side by side may detect light beams from other transmitters, resulting in unstable detection. The problem may be solved by separating the sensors by a specified distance. This graph is used to determine that distance.

Ex. FS2-65, FU-4F

0

6

4

10 20 30

5

2

1

3

Detectingdistance

ON OFF

Detecting distance X (mm inch)

Target: 50 x 50

Hys

tere

sis

(mm

inch

)

Hysteresis

White mat paper

0.24"

0.20"

0.16"

0.12"

0.08"

0.04"

0.39" 0.79" 1.18"

1.97" x 1.97"

This graph shows the level of hysteresis measured at various set distances.

6. ConnectionsParallel connection (OR logic circuit) and serial connection (AND logic circuit)

Example: OR logic circuit (for NPN open-collector output sensors)

BlueLoad

12 to 24 VDC

Brown

Blue

Brown

Black

Black

Connection to PLCNPN open-collector type

Blue (0 V) 24 VDC

Brown (+) COM

PLC (KV Series)

INBlack (output)

Example: AND logic circuit (for NPN open-collector output sensors)

External relay

N.C.

Load Powersupply

Connect the external relay as N.C.

12 to 24 VDC

Blue

Brown

Blue

Brown

Black

Black

* For AND circuit, select the operation mode opposite of that actually required. If LIGHT-ON output is required, select the DARK-ON mode.

PNP open-collector type

Blue (0 V)24 VDC

Brown

PLC (KV Series)

IN

Black (output)

COM

Page 9: 754 Photoelectric Sensors - İmtek · 754 Photoelectric Sensors Photoelectric ... glass, metal, plastics, ... Fiber Photoelectric Sensors The photoelectric sensor incorporates optical

TEC

HN

ICA

L G

UID

E762

Photoelectric Sensors

Safety Light Curtains

Ultrasonic Sensors

Proximity Sensors

Pressure Sensors

PLCs

Counters

Barcode Readers

Vision Systems

Displacement Sensors

Optical Micrometers

Communication Method

Microscope

Laser Markers

Enclosure Rating

Photoelectric Sensors

www.keyence.com762

7. Hints on Correct Use1. MountingType External disturbance Solution

Thrubeam

Target

The receiver may detect a light beam reflected by the mounting surface.

Target

Light-shield

Position a light-shield so that the receiver will not detect a light beam travelling below the target.

Target

Readjust the mounting height

Raise the mounting position of the sensor head.

Reflective

A rough mounting surface may reflect the light beam, causing unstable detection.

Readjust the mounting heightChange the mounting height, or angle of the sensor head.

Target

An object in the background may reflect the light beam, causing unstable detection.

Black background

Target

Provide a background object of low reflectance, such as a black wall, to prevent the sensor from detecting a reflected light beam.

Target

Providedistance

Provide as great a distance as possible between the target and background object.

The small-spot definite-reflective type or fixed-distance type, whose detection is not affected by background objects, is recommended in cases where the above solutions are not possible.

2. Alignment of optical axis (thrubeam type)

1. Place the transmitter and the receiver face-to-face in a straight line.

2. Rotate the receiver clockwise or counterclockwise to find the range where the indicator LED lights. Set the receiver at the mid-point of the range.

3. Follow the same procedure for vertical alignment.

Transmitter Receiver

3. Mounting environment• Detecting shiny targets (retro-reflective type)

To detect mirror-surfaced targets, a retro-reflective type sensor with the P.R.O. (polarized reflective options) function (PZ2-61) is recommended. A sensor with the P.R.O. function has an optical system which is constructed so that the emitter emits only the horizontal component of the light wave and the receiver receives only the vertical component.

This allows mirror-surfaced targets to be stably detected.

The horizontal component ofthe light wave is emitted.

Reflector

When the horizontal component of the light wave strikes against the reflector, it scatters in all directions.

The horizontal component ofthe light wave is emitted.

Reflector

When the polarized light wavestrikes against a mirror-surfacedtarget, it does not scatter.

When using a retro-reflective type sensor that is not equipped with P.R.O. function, install the sensor head so that the distance from the target (L) is as far as possible, and the optical axis is at 30 to 45 degree-angle to the target.

L

Reflector

30° to 45° Target

Page 10: 754 Photoelectric Sensors - İmtek · 754 Photoelectric Sensors Photoelectric ... glass, metal, plastics, ... Fiber Photoelectric Sensors The photoelectric sensor incorporates optical

TECH

NIC

AL G

UID

E763

Photoelectric Sensors

Safety Light Curtains

Ultrasonic Sensors

Proximity Sensors

Pressure Sensors

PLCs

Counters

Barcode Readers

Vision Systems

Displacement Sensors

Optical Micrometers

Communication Method

Microscope

Laser Markers

Enclosure Rating

Photoelectric Sensors

763www.keyence.com

• InterferenceWhen 2 or more sensors are installed side-by-side without sufficient distance between adjacent sensors, the receiver may detect a light beam emitted from the receiver of another unit, disturbing sensor operation. This phenomenon is called interference.

Suggestions for eliminating interference1. Use a sensor head with interference-prevention.

(Interference-prevention type sensors can be mounted side-by-side.)

2. Use a sensor head that can be switched to an alternate frequency. (Can be closely mounted.)

3. Allow sufficient distance between sensor heads to prevent interference. For further information, refer to the “Interference area” characteristics chart for each model.

Interference area

Detecting distance X

Dis

tanc

e Y

Operation area

4. For the thrubeam type sensor, alternate the placement of the transmitters and receivers.

Transmitter Receiver

Receiver Transmitter

* Set the transmitters and receivers so that a light beam emitted from a transmitter will not be received by the receiver of the adjacent sensor.

• Ambient light and effect of external lightKEYENCE photoelectric sensors employ the pulse light emission method, which ensures stable operation when external light is strong. However, a strong light beam, emitted in the direction of the optical axis of the receiver, will cause the sensor to malfunction. To correct this, change the angle of the sensor head, or provide a light-shield to prevent an external light beam from being emitted directly to the receiver.

Light-shield

External light beam

Sensor head angle

Illumination

Illuminance (lux) Conditions

1000,000 Sunlight - clear sky

10,000 Sunlight - cloudy sky (32,000 lux)

1,000 Design office (1,000 to 1,500 lux)

100 Department stores (500 to 700 lux)

10Candlelight at a distance of 30 cm 11.81" (15 lux)

4. Miscellaneous• When using a commercially available switching

regulator, ground its chassis grounding and earth grounding terminals.

• Isolate the sensor wiring from power lines and high voltage lines; otherwise, the sensor may malfunction due to noise interference.

• Handle the photoelectric sensor carefully when mounting. Strong impact to the sensor head may damage the sensor’s waterproof capability.

8. General SpecificationsVibration:10 to 55 Hz, 1.5 mm 0.06" double amplitude in X, Y, and Z directions, 2 hours respectively. FS-T, FS-M, FS-V, FS2, LV, CZ-K, CZ-V, PZ-V/M, PZ2, PS-T, PQ, PG, PI-G, PW, GV and PX Series.

Shock:• 500 m/s2 1640.4' (approx. 50 G) in X, Y, and Z

directions, 3 times respectively FS-T, FS-M, FS-V, FS2, PS-T, PQ and CZ-K Series• 1,000 m/s2 3280.8' (approx. 100 G) in X, Y, and Z

directions, 6 times respectively PZ-V/M, PZ2 and PZ-G Series

• 300 m/s2 984.3' (approx. 30 G) in X, Y, and Z directions, 3 times respectively

PI-G Series• 100 m/s2 328.1' (approx. 10 G) in X, Y, and Z

directions, 3 times respectively PW Series

Power supply ripple (p-p): 10% max.All DC types