Retroreflective sensor alignment – Banner PicoDot PD Series User Manual

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305 mm (12 inch) Focus

Models

Cable

Output

Type

Excess Gain

Beam Width

PD49VN6C300

2 m (6.5 ft) cable

NPN

1

10

100

10 mm

0.4 in.

100 mm

4 in.

1000 mm

40 in.

1 mm

0.04 in.

1000

DISTANCE

300 mm (12 in.) PicoDot

Convergent Mode

EXCESS

GAIN

375 mm

14.0 in

300 mm

12.0 in

225 mm

8.0 in

150 mm

6.0 in

75 mm

3.0 in

0

0

1 mm

2 mm

3 mm

1 mm

2 mm

3 mm

0

0.04 in

0.08 in

0.12 in

0.04 in

0.08 in

0.12 in

DISTANCE

300 mm (12 in) PicoDot

Convergent Mode

PD49VN6C300Q

5-pin Euro-style QD

150 mm (6 in) pigtail

PD49VP6C300

2 m (6.5 ft) cable

PNP

PD49VP6C300Q

5-pin Euro-style QD

150 mm (6 in) pigtail

Retroreflective Sensor Alignment

Because the PicoDot laser sensor has such a long sensing range, and because its beam is so narrow (compared to the

beam of typical retro sensors), its alignment is somewhat less forgiving and more difficult to accomplish. As indicated, the

effect of angular misalignment can be dramatic, especially over distance. For example, with one 51 mm (2 in) reflective

target mounted at a distance of 6 m (20 ft) from the sensor, only one degree of angular misalignment will cause the

center of the laser beam to miss the center of the target by 102 mm (4 in), and miss the target altogether by almost 76

mm (3 in).

Alignment tip: When using a small retroreflective target at medium or long range, it is often useful to temporarily attach

(or suspend) a strip of retroreflective tape (such as BRT-THG-2-100) along a line that intersects the real target. The visible

red laser beam is easily seen in normal room lighting; sight along the beam toward the target, from behind the sensor.

Move the sensor to scan the laser beam back and forth across the tape strip, to guide the beam onto the target.

The use of mounting bracket SMB-46A may simplify alignment, because of its precision-positioning feature. After mounting

the bracket and the sensor, tighten the screws in the two corners of the bracket to position the beam in the exact spot

needed.

Ø = Misalignment Angle

Y = X(tan Ø)

X

Laser

Emitter

Y

Ø

Figure 1. Beam displacement per degree of misalignment

Distance (X) To Retro Target

Beam Displacement (Y) for 1°

of Misalignment

1.5 m (5 ft)

25 mm (1 in)

3 m (10 ft)

50 mm (2 in)

6 m (20 ft)

100 mm (4 in)

15 m (50 ft)

250 mm (10 in)

30 m (100 ft)

500 mm (20 in)

PD49 Series Ruggedized PicoDot

®

P/N 67450 Rev. B

www.bannerengineering.com - tel: 763-544-3164

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