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Expandable Area SensorPJ series

Base Unit


[Discontinued model]

This model has been discontinued.

Compliance with the certification standard is ensured as of the time of shipment from our company.

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Base unit

Number of optical axes


No. of connectable units

8 (base unit × 1 + extension unit A or B × 7) or less*1

Beam axis spacing


Maximum optical axis number

64 (PJ-F20 × 1 + PJ-F21 × 7)*3

Detection area

140 mm (8 optical axes) to 1,260 mm (64 optical axes)*4

Detecting distance


Detectable object

Opaque material with a diameter of 28 mm or more

Light source

Infrared LED

Indicator lamp

A string of 8, 2-Colour LEDs (red and green) for the transmitter and receiver

Response time

When output turned off : 7.5 ms or less, when output turned on : 15 ms or less


Operation mode

Turned on when light is being applied to all optical axes

Self-diagnostic output

Turned off when an error (control output damage, transmitter element or circuit damage, receiver element or circuit damage, ambient light input, cable disconnections, and LSI errors) is detected

Protection circuit

Overcurrent protection, surge absorber, reversed polarity protection



4-core shielded cable (0.5 mm2), length : 7 m, gray sheath


4-core shielded cable (0.5 mm2), length : 7 m, black sheath


Use a shielded cable with a nominal cross section of 0.5 mm2 or more to extend the cable by up to 20 m for both the transmitter and receiver.


Output specifications

Maximum NPN open-collector output : 100 mA (40V or less), residual voltage : 1.0 V or less

Self-diagnostic output


Power voltage

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

Current consumption

130 mA (total of T, R)

Environmental resistance

Enclosure rating


Ambient light

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

Ambient temperature

-10 to +55 °C (No freezing)

Relative humidity

35 to 95 % RH (No condensation)

Vibration resistance

10 to 55 Hz, Double amplitude 0.7 mm, 20 times in each of the X, Y, and Z directions

Shock resistance

100 m/s2, 1,000 times in each of the X, Y, and Z directions


Case : aluminum, lens cover : polyarylate


Approx. 1,450 g

*1 Mixed expansion at a 20 mm or 40 mm pitch is possible. The number of units that can be connected in a mixed expansion is 8 units or less.
*2 When the PJ-F41 / F42 has been added to the PJ-F20 / F21, the optical axis pitch of added unit is 40 mm, and 20 mm when the PJ-F21 / F22 has been added to the PJ-F40 / F41.
*3 When performing mixed expansion at a 20 mm or 40 mm pitch, there is no limit on the number of axes if the number of connected units is 8 or less.
*4 With mixed expansion, this becomes 140 mm [when the PJ-F20 is used] or 120 mm [when the PJ-F40 is used] +20 mm x (the number of 20 mm pitch extension optical axes) +40 mm x (the number of 40 mm pitch extension optical axes).

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