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Expandable Area SensorPJ series

Base Unit



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Number of optical axes


Beam axis spacing

40 mm

Maximum optical axis number

28 optical axes (PJ-50A x 1 + PJ-55A x 12)

Detection area

120 mm (4 optical axes) to 1080 mm (28 optical axes)

Detecting distance

5 m

Detectable object

Opaque materials (50 mm dia. min.)

Light source

Infrared LED

Indicator lamp

Output (PJ-50AR)/Power (PJ-50AT) : Red LED, Stable operation (PJ-50AR) : Green LED

Response time

15 ms or less


Control output

NPN open collector 100 mA max. (40 V max.), Residual voltage : 1 V max.


Operation mode

LIGHT-ON/DARK-ON (switch-selectable)

Noise resistance (power supply line)

350 V, 1 µs (noise simulator)

Protection circuit

Reversed polarity, overcurrent protection, surge absorber


Power voltage

12 to 24 VDC ±10 %, Ripple (P-P) 10 % or less

Current consumption

90 mA (PJ-50AT: 35 mA, PJ-50AR: 55 mA)*1

Environmental resistance

Enclosure rating


Ambient light

Incandescent lamp: 3,500 lux or less, Sunlight: 12,000 lux or less

Ambient temperature

-20 to +50 °C (No freezing)

Relative humidity

35 to 85 % RH (No condensation)

Vibration resistance

10 to 55 Hz, Double amplitude 1.5 mm, 2 hours in each of the X, Y, and Z directions

Shock resistance

100 m/s2, 3 times in each of the X, Y, and Z directions


Housing : Glass-fi bre reinforced plastic, Lens cover : PFA


PJ-50AT: Approx. 390 g, PJ-50AR: Approx. 395 g*2

*1 This is the value with a power supply voltage of 24 V. (80 mA for the PJ-50A, 20 mA for the PJ-55A, and 45 mA for the PJ-56 with a power supply voltage of 12 V.)
*2 For models PJ-50AT and 50AR, the weight of the 5-m cable is included.

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