Photoelectric Sensors

Photoelectric sensors detect and measure physical objects or quantities by emitting a field or beam of electromagnetic radiation, an object is detected by measuring alterations in the return signal. There are 3 main types of photoelectric sensors which provide reliable detection, these are through-beam, retro-reflective and diffuse. The basic function of each is to detect the presence or absence of objects or measure the distance to the object.


Through-beam Sensors


Through-beam sensors (aka thru-beam) rely on two separate housings, one for the transmitter and one for the receiver, with the transmitter providing a continuous beam of light to the receiver. Each time an object passes through the beam this interrupts the signal between the transmitter and receiver, which in turn causes the receiver to send an electrical signal to the output. Through-beam sensors are suited to long-distance sensing and are capable of detecting almost any object, irrespective of colour or angular motion.


Retro-reflective Sensors


Retro-reflective photoelectric sensors (retroreflective) have both the transmitter and receiver contained within the same housing but require a reflector opposite to the sensor. The reflector bounces the light beam back to the transmitter until an object breaks the beam. Objects which are highly reflective such as aluminium require sensors with polarising filters. The filter allows the sensor to acknowledge that the reflected light from reflecting materials is different from the reflector.


Diffuse Sensors


Diffuse sensors (proximity sensor) are easier to install as only one device has to be mounted. This is because the transmitter and receiver are contained within one housing. Diffuse sensors use the reflection from the target object within a predetermined sensing range. The transmitter sends out a continuous beam of light, once this hits the target it is diffused in all directions, a part of this light is reflected back and recognised by the receiver, the receiver then sends an electrical signal to the output.


A special type of diffused mode is background suppression which enables the user to precisely control the sensing range. A diffuse mode sensor with background suppression is less sensitive to the target colour. They can also use a visible red light or infrared light sources.


...
Read more Read less

Filters

Viewing 1 - 20 of 241 products
Results per page
Description Price Sensor Style Detection Type Detection Range Output Type Electrical Connection Maximum AC Voltage Maximum DC Voltage Terminal Type Light Source IP Rating Maximum Current Interface Response Time Housing Material
RS Stock No. 289-2491
Mfr. Part No.WL150-P430
BrandSick
£100.92
Each
Units
Block Retroreflective 2.4 m PNP 4-Pin M8 Connector - 30V - LED IP67 100 mA - <=0.5 ms ABS, PMMA
RS Stock No. 288-9805
Mfr. Part No.WT150-P460
BrandSick
£123.69
Each
Units
Block Diffuse 2 100 mm PNP 4-Pin M8 Connector - 30V - LED IP67 100 mA - <=0.5 ms ABS, PC
RS Stock No. 358-7926
Mfr. Part No.WL260-R270
BrandSick
£135.58
Each
Units
Block Retroreflective 0.01 15 m Relay 5-Terminal Screw 240V 30V - LED IP67 3 A - <=20 ms ABS
RS Stock No. 122-0713
Mfr. Part No.WL100-2P4439
BrandSick
£67.71
Each
Units
Block Retroreflective 0.01 7.2 m PNP 4-Pin M8 Connector - 30V M8 Connector LED IP67 30 mA - 0.5 ms ABS, PC, POM
RS Stock No. 493-7287
Mfr. Part No.WL18-3P430
BrandSick
£144.93
Each
Units
Block Retroreflective 7 m PNP 4-Pin M12 Connector - 30V - LED IP65, IP67 100 mA - 500 μs ABS
RS Stock No. 458-828
Mfr. Part No.WL12-3P2431
BrandSick
£142.79
Each
Units
Block Retroreflective 7 m PNP 4-Pin M12 Connector - 30V - LED IP69K 100 mA - <=330 μs Metal
RS Stock No. 360-0451
Mfr. Part No.WT24-2R210
BrandSick
£275.83
Each
Units
- - - Relay - - - - LED IP69 - - <=10 ms Die Cast Zinc
RS Stock No. 770-7008
Mfr. Part No.WL250-2R1531
BrandSick
£123.42
Each
Units
Block Retroreflective 0.01 15 m Relay 5-Wire Cable 2m 240V 240V - LED IP67 - - <=15 ms ABS
RS Stock No. 458-840
Mfr. Part No.WTB12-3P2411
BrandSick
£201.96
Each
Units
- - - PNP - - - - LED IP66, IP67, IP69 - - <=330 μs Metal
RS Stock No. 458-844
Mfr. Part No.WL12G-3B2531
BrandSick
£195.53
Each
Units
Block Retroreflective 4 m NPN/PNP 5-Pin M12 Connector - 30V - LED IP69K 100 mA - <=330 μs Metal
RS Stock No. 493-7259
Mfr. Part No.WT18-3P430
BrandSick
£213.81
Each
Units
Block Diffuse 50 600 mm PNP 4-Pin M12 Connector - 30V - LED IP67 100 mA - <700 μs ABS
RS Stock No. 219-027
Mfr. Part No.DT20-P244B
BrandSick
£639.54
Each
Units
Block Background Suppression 100 300 mm Analogue 5-Pin M12 Connector - 30V - Laser Light IP65 100 mA - 2.8 ms Metal
RS Stock No. 530-0939
Mfr. Part No.WTB4-3P2161
BrandSick
£126.05
Each
Units
Block Diffuse 4 150 mm PNP 3-Pin M8 Connector - 30V - LED IP66, IP67 100 mA - <0.5 ms Bayblend, PMMA
RS Stock No. 288-9776
Mfr. Part No.WT150-P430
BrandSick
£100.92
Each
Units
Block Diffuse 10 250 mm PNP 4-Pin M8 Connector - 30V - LED IP67 100 mA - <=0.5 ms ABS, PC
RS Stock No. 763-7882
Mfr. Part No.WTB12-3P2431
BrandSick
£201.96
Each
Units
Block Background Suppression 20 350 mm PNP 4-Pin M12 Connector - 30V - LED IP66, IP67, IP69K 100 mA - <=300 μs Metal
RS Stock No. 768-9461
Mfr. Part No.WL9-3P2430
BrandSick
£102.85
Each
Units
Block Retroreflective 0 4 m PNP 4-Pin M12 Connector - 30V - LED IP66, IP67, IP69K 100 mA - <0.5 ms Al2O3
RS Stock No. 218-989
Mfr. Part No.WT100L-F2241
BrandSick
£127.88
Each
Units
Block Diffuse 450 mm PNP 4-Pin M8 Connector - 30V - Laser Light IP65 100 mA - <0.25 ms ABS, PMMA
RS Stock No. 371-4651
Mfr. Part No.VL18-3P3840
BrandSick
£78.54
Each
Units
Barrel Retroreflective 0.005 → 3.7 m PNP 4-Pin M12 Connector - 30V - LED IP67 100 mA - <=2 ms PBT, PC
RS Stock No. 218-973
Mfr. Part No.WL100L-F2231
BrandSick
£127.88
Each
Units
Block Retroreflective 0.08 12 m PNP 4-Pin M8 Connector - 30V - Laser Light IP65 100 mA - <0.25 ms ABS, PMMA
RS Stock No. 701-8803
Mfr. Part No.WLG4S-3P2232V
BrandSick
£163.80
Each
Units
Block Retroreflective 5 m PNP 4-Pin M8 Connector - 30V - LED IP69K 100 mA - <=0.5 ms Stainless Steel