Products Detail


Photoelectric SwitchU-Shaped

Die-casting case is applied!
Sensing distance is 30mm and 50mm!



-> Die-casting case is applied! Sensing distance is 30mm and 50mm!
-> Any adjustments are not required
-> High repeatability
-> Relay output type is lined-up







Kind Through-beam type
Model No. FG-31C FG-51C
Light source Infra-red LED
Power source 12 to 24VDC(±10%, Ripple 5% or less)
Current consumption 50mA or less
Distance between projector and receiver 30mm(fixed) 50mm(fixed)
Detectable objects Opaque object with φ2mm or more Opaque object with φ10mm or more
Operating mode Light-ON/Dark-ON(changeover by cable)
Control output NPN transistor/open-collector output,
Allowable load voltage : 30V or less,
Allowable load current : 100mA or less,
Response time 1msec or less
Indicators Operating lamp : red/green LED(Green lights up when light-entering, Red lights up when light-interruption)
Connection Cable type(3m long, 0.3mm2 )
Ambient illuminance Incandescent lamp : 10,000lx or less
Ambient temperature/humidity -10 degrees C to +50 degrees C, 45 to 85%RH
Vibration resistance Double amplitude 1.5mm, 10 to 33Hz, Each 2 hour in X, Y and Z directions
Impact resistance 100m/s2, Each 3 time in X, Y and Z directions
Protective structure IP40(IEC standard)
Case materials Aluminum die-casting case
Weight Approx. 340g Approx. 360g

External dimension




Caution items
* Don't make parallel wiring with power line etc. because of avoiding surge or induction if cable would extend.
* Make sure to wipe the lens surface with soft clothes etc. because it may cause malfunction.
* Don't detect registered marking or transparent objects.
* If it would detect the glossy object such as metal plate etc., it may be affected by disturbance light such as sun light. In case that, install the cover for shading or paint the object in black

I/O Circuit

Input/output circuit

Input/output circuit
1. In case of Light-ON operation
2. In case of Dark-ON operation


Control output(1) : In case of Light-ON operation
Control output(2) : In case of Dark-ON operation


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