Owner's manual

MINI-BEAM
®
Sensors - SM2A312DBZ and SM2A312W
page 2
Banner Engineering Corp. • Minneapolis, U.S.A.
Website: http://www.baneng.com • Tel: [phone]
MINI-BEAM Installation and Alignment
Proper operation of a SM2A312W or SM2A312DBZ sensor requires that it be
mounted securely and aligned properly. The wide-angle optics of these sensors
makes sensor alignment very forgiving.
1) Begin with the sensor at the desired distance from the object to be sensed, and
at the approximate position where it will be mounted. Any background should be
as far behind the object as possible (at least three times the sensor-to-object
distance), and as dark in color as possible, compared to the object. Ideally, the
object should present its largest reflective surface to the sensor.
2) Switch the sensor to light operate mode (see below). Apply power to the sensor,
and advance the 15-turn Gain control to maximum (clockwise end of rotation).
If the sensor is “seeing” its reflected light, the sensor alignment LED should be
ON. Move the sensor up-down-right-left (include angular rotation) to find the
center of the movement zone within which the LED remains lit. Reducing the
Gain setting (if necessary) will reduce the size of the movement zone and make
more precise alignment possible.
3) Repeat the alignment motions after each Gain reduction. When alignment is
optimized, mount the sensor solidly in that position. Increase the Gain setting to
maximum. Test the system by removing the object from the sensing position.
The Alignment LED indicator should go OFF. If the LED indicator does not go OFF,
the sensor is reacting to light reflected from a background surface. Reduce the
Gain setting until the Alignment indicator goes OFF, plus two additional full turns.
Again place the object in the sensing position. If the Alignment indicator does
not come ON, the sensor is receiving as much or more light energy from the
background as from the object. Consider the following alternatives:
a) move the sensor closer to the object and reduce the sensitivity (gain);
b) reduce background reflectivity by painting the background with flat-black
paint, or by scuffing the background or cutting a hole through it;
c) tilt the sensor or the background so that the sensing beam is not
perpendicular to the background.
Light/Dark Operate Selection:
• Turn switch fully clockwise for light operate (sensor outputs conduct when object
is present).
• Turn switch fully counterclockwise for dark operate (sensor outputs conduct
when object is absent).
15 Turn
Gain
Adjustment
and Light/Dark
Operate Switch
Gasketed
Acrylic Cover
Indicator LED Lights when the
sensor's output is conducting
Object
Up
Down
Left
Right
SM2A312DBZ or
SM2A312W
Figure 1. Diffuse mode alignment
Figure 2. SM2A312W and SM2A312DBZ
features