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 180 products
Results per page
Description Price Sensor Style Detection Type Detection Range Output Type Electrical Connection Maximum AC Voltage Communication Protocol Maximum DC Voltage Terminal Type Light Source IP Rating Maximum Current Interface Response Time
RS Stock No. 450-2954
Mfr. Part No.OBT200-18GM60-E5-V1
HK$848.23
Each
units
Barrel Diffuse 200 mm PNP 4-Pin M12 Connector - - 30V - Infrared IP67 100 mA - <=1 ms
RS Stock No. 817-1557
Mfr. Part No.RL31-8-1200-RT/73c/136
HK$625.69
Each
units
Block Diffuse 1200 mm Push Pull 4-Pin M12 Connector - - 30V - LED IP67 100 mA - <=1 ms
RS Stock No. 817-1560
Mfr. Part No.RL31-8-2500-IR/73c/136
HK$610.69
Each
units
Block Diffuse 2500 mm Push Pull 4-Pin M12 Connector - - 30V - LED IP67 100 mA - <=1 ms
RS Stock No. 450-2904
Mfr. Part No.OBS4000-18GM60-E5
HK$977.02
Each
units
Barrel Retroreflective 4 m PNP Cable - - 30V - LED IP67 100 mA - 1 ms
RS Stock No. 510-3255
Mfr. Part No.RLK29-55/25/116-SET
HK$1,109.21
Each
units
Block Retroreflective 12 m Relay 6-Terminal Screw 230V - 230V - LED IP67 2 A - 50 ms
RS Stock No. 450-2948
Mfr. Part No.OBT200-18GM60-E5
HK$777.61
Each
units
Barrel Diffuse 200 mm PNP 4-Wire Cable 2m - - 30V - Infrared IP67 100 mA - <=1 ms
RS Stock No. 714-1669
Mfr. Part No.M100/MV100-RT/76a/95/103
HK$907.55
Each
units
Block Through Beam (Emitter and Receiver) 10 m PNP 4-Pin M8 Connector - - 30V - LED IP67 100 mA - 0.5 ms
RS Stock No. 891-9514
Mfr. Part No.RLK31-8-2500-IR/31/115
HK$666.68
Each
units
Block Diffuse 0 → 2500 mm Relay 5-Wire Cable 2m 240V - 240V - Infrared IP67 40 mA - 25 ms
RS Stock No. 124-0330
Mfr. Part No.OBE20M-R101-S2EP-IO-V31-L
HK$1,311.50
Each
units
Block Through Beam (Emitter and Receiver) 0 → 20 m NPN/PNP 4-Pin M8 Connector - IO-LINK 30V 4-Pin Connector Laser Light IP67, IP69, IP69K 100 mA IO-Link 0.4 ms
RS Stock No. 450-2897
Mfr. Part No.OBS4000-18GM60-E4-V1
HK$849.58
Each
units
Barrel Retroreflective 4 m NPN 4-Pin M12 Connector - - 30V - LED IP67 100 mA - 1 ms
RS Stock No. 404-027
Mfr. Part No.GLV18-8-200-S/25/102/159
HK$575.86
Each
units
Barrel Diffuse 200 mm NPN 3-Pin M12 Connector - - 30V - LED IP67 100 mA - <=1 ms
RS Stock No. 463-8384
Mfr. Part No.RLK39-54/31/40A/116
HK$2,241.41
Each
units
Block Retro-Reflective 7 m Relay 4-Terminal Screw 240V - 240V - LED IP67 3 A - <=20 ms
RS Stock No. 510-3126
Mfr. Part No.ML7-8-200/25/102/143
HK$1,237.38
Each
units
Block Diffuse 20 → 200 mm NPN 4-Pin M8 Connector - - 30V - LED IP69K 100 mA - 0.5 ms
RS Stock No. 124-0325
Mfr. Part No.OMT100-R100-2EP-IO-V31
HK$2,736.79
Each
units
Block Background Suppression 40 → 100 mm NPN/PNP 4-Pin M8 Connector - IO-LINK 30V 4-Pin Connector LED IP67, IP69, IP69K 100 mA IO-Link 2 ms
RS Stock No. 463-8390
Mfr. Part No.RLK39-54-Z/31/40A/116
HK$2,073.96
Each
units
Block Retro-Reflective 7 m Relay 4-Terminal Screw 240V - 240V - LED IP67 3 A - <=20 ms
RS Stock No. 447-159
Mfr. Part No.GL10-RT/32/40A/98A
HK$2,116.10
Each
units
Fork Through Beam (Fork) 10 mm PNP 3-Pin M8 Connector - - 30V - LED IP67 200 mA - 0.2 ms
RS Stock No. 404-051
Mfr. Part No.GLV18-8-450/25/102/159
HK$562.07
Each
units
Barrel Diffuse 450 mm NPN 3-Pin M12 Connector - - 30V - LED IP67 100 mA - <=1 ms
RS Stock No. 817-1605
Mfr. Part No.RLK31-54/31/115
HK$676.66
Each
units
Block Retroreflective 9000 mm Push Pull 5-Wire Cable 2m 240V - 240V - LED IP67 3 A - <=25 ms
RS Stock No. 510-3132
Mfr. Part No.ML7-8-200/25/103/115
HK$1,237.38
Each
units
Block Diffuse 20 → 200 mm PNP 3-Wire Cable 2m - - 30V - LED IP69K 100 mA - 0.5 ms
RS Stock No. 404-033
Mfr. Part No.GLV18-8-200-S/115/120
HK$562.07
Each
units
Barrel Diffuse 200 mm PNP Cable - - 30V - LED IP67 100 mA - <=1 ms