Supplemental Information

Understanding Sensing Modes . . . . . . . . . . . . . . . . . . . . .672

Output Types . . . . . . . . . . . . . . . . . . . . . . .674

Sensing Terms Performance Specifications . . . . . . . . . . . . .675

Environmental Ratings . . . . . . . . . . . . . . . .676

Data Reference Table 1 - Units for Photoelectric Specs . . . . . .677

Table 2 - Unit Prefixes . . . . . . . . . . . . . . . . .677

Tables
Table 3 - English Metric Conversion . . . . . . . .678
Table 4 - Drill Sizes for Mounting Hardware . .678
Table 5 - Velocity Conversion . . . . . . . . . . . .679
Table 6 - Velocity Conversion Factors . . . . . . .680
Table 7 - Length Conversion Factors . . . . . . .680
Table 8 - Temperature Conversion . . . . . . . . .681
Table 9 - Trig Functions & Formulas . . . . . . .682
Basic Electrical Formulas . . . . . . . . . . . . . .683
Table 10 - Resistor Color Codes . . . . . . . . . .683
Table 11 - Copper Wire Information . . . . . . . .684
Table 12 - Hazardous Classifications . . . . . . .685
Table 13 - Nema Ratings . . . . . . . . . . . . . . .686
Table 14 - IP Enclosure Ratings . . . . . . . . . .686
Table 15 - Chemical Resistance of Sensor . . .687
Housing Materials & Lenses

International Europe . . . . . . . . . . . . . . . . . . . . . . . . . . .688

Africa and Middle East . . . . . . . . . . . . . . . .689

Distributor List Asia and the Pacific Rim . . . . . . . . . . . . . . .689

The Americas . . . . . . . . . . . . . . . . . . . . . .690

Banner Engineering Corp. Minneapolis, U.S.A.

Website: http://www.baneng.com Tel: 612.544.3164 SUPPLEMENTAL INFORMATION 671
Understanding Sensing Terms - Sensing Modes
MBIENT LIGHT RECEIVERS: Ambient light receivers, such as
A MULTI-BEAM model SBAR1, are operated by sunlight, room light,
or laser light sources. These sensors are also used to sense the large
amounts of infrared light (heat energy) emitted by hot or molten
glass, metal, or plastic during processing of these materials.

PPOSED (A.K.A. THROUGH-BEAM) SENSING MODE:

O The opposed mode requires a separate emitter and receiver that are
positioned opposite each other so that the light from the emitter shines
directly on the receiver. An object is sensed when it interrupts the light
beam. The opposed mode is the most efficient use of photoelectric
sensing energy, and offers the highest level of excess gain for reliable
sensing through dirt, fog, or other challenging environments.

ETROREFLECTIVE (A.K.A. RETRO) SENSING MODE:

R Retroreflective mode sensors have both the emitter and the
receiver in the same housing. A light beam is established between the
sensor and a special retroreflective target (see page 636). An object is
sensed when it interrupts the light beam. Retro is the most popular
sensing mode for conveyor control and similar applications where
there is an advantage to have a sensor on only one side of the sensing
P process. Polarized retroreflective sensors are used when the object to
be detected is highly reflective. Special laser retro sensors, such as
Q45LL (pages 122 and 438), offer very long range and accurate
sensing repeatability.

IFFUSE (A.K.A. PROXIMITY) SENSING MODE: Diffuse mode

D sensors contain both the emitter and the receiver in the same
housing. An object is detected when the receiver captures the small
percentage of emitted light that is reflected back to the sensor from
the surface of the object itself. Minimal lensing is used so as to
project the emitted light in a broad (diffused) pattern and give the
receiver a wide field of view. Special models called divergent mode
sensors use no lenses at all for extremely forgiving alignment to
objects that are difficult for reflective sensors to sense, such as clear
materials and very small parts.

ONVERGENT BEAM SENSING MODE: The convergent mode is

C similar to the diffuse sensing mode because an object is sensed
when the receiver sees light reflected back to the sensor by the
object itself. Unlike diffuse mode sensors, however, convergent
sensors use additional optics to produce a small and well-defined
sensing area, focused at a fixed point ahead of the sensor lens.
Because convergent sensors make much more efficient use of
sensing light energy, they can sense relatively non-reflective
materials and objects with small reflective surfaces. They are,
however, much less forgiving to sensing distance, as compared to
diffuse mode sensors.

672 SENSING MODES Banner Engineering Corp. Minneapolis, U.S.A.

Website: http://www.baneng.com Tel: 612.544.3164
 Understanding Sensing Terms - Sensing Modes
IXED-FIELD AND ADJUSTABLE FIELD SENSING MODES: Fixed-
Fsensing
field sensors use two receivers and a comparator circuit to cancel
response whenever the intensity of the reflected light
reaching the long-range receiver exceeds the intensity of the reflected
light reaching the close-range receiver. As a result, any object lying
beyond the sensors fixed cutoff point can be reliably ignored.
Adjustable field sensors use an array of multiple receiver elements,
which allows the sensor circuitry to move the locations of the cutoff
point with a simple adjustment.

IBER OPTIC SENSING MODES: Transparent fibers of glass or

F plastic may be used for conducting and guiding photoelectric
sensing light energy. Individual fibers are usually used in pairs for
opposed mode sensing. Bifurcated fibers combine the emitted and
received light in the same assembly, and are usually used for diffuse
mode sensing. Bifurcated fiber optics are sometimes fitted with an
optional lens for retroreflective mode sensing. Fiber optics comprise
the smallest photoelectric sensors and can fit into extremely tight
spaces. Most glass fiber optics are able to withstand sensing
environments where there are corrosive materials and/or where the
temperature is too high for sensor electronics. Most sensor families
include models for use with fiber optics.

IGHT SCREENS (A.K.A. LIGHT CURTAINS): A light screen is an

Lanywhere
array of photoelectric beams configured to sense objects passing
through an area (i. e. - through a sensing plane). Some
light screens, such as MINI-ARRAY or BEAM-ARRAY models work
together with a microprocessor-based controller to measure and/or
profile one dimension of an object that passes through the sensing
plane. Other light screens, such as LS Series sensors (page 458), are
designed simply for sensing the presence of a part in the sensing
plane, and are usually used for parts counting or die ejection
verification. Safety light screens, such as the MINI-SCREEN, include
the necessary self-checking redundant circuitry necessary to allow
their use in personnel safety applications. See the Banner Machine
Safety Products Catalog and the Important Safety Warning inside
the front cover of this catalog.

LTRASONIC SENSING MODES: Ultrasound may be used for

U opposed mode or reflective proximity mode detection of clear
materials and other objects that are difficult to detect with
photoelectric sensors. Ultrasonic proximity mode sensors can
measure the time delay between the emitted sound and the returned
echo, and produce an accurate measurement of sensing distance.
Ultrasonic analog proximity sensors produce an output that has a
highly linear relationship to sensing distance. Ultrasonic proximity
sensors with switched outputs, such a OMNI-BEAM and Q45U
models, offer a high/low level mode that can directly control fill
level of liquids or solids. (See the Banner Measurement and Inspection
Sensor Catalog)

Banner Engineering Corp. Minneapolis, U.S.A.

Website: http://www.baneng.com Tel: 612.544.3164 SENSING MODES 673
Understanding Sensing Terms - Output Types
NALOG RESPONSE: Most sensors offer a switched (discrete)
A output. Sensors with an analog output produce a variable voltage or
current that is proportional to some sensing parameter. The output of
an analog photoelectric sensor is proportional to the strength of the
received light signal (see Analog OMNI-BEAM sensors, page 44). The
output of an analog ultrasonic proximity mode sensor is proportional to
the distance from the sensor to the object that is returning the sound
echo. (See the Banner Measurement and Inspection Sensor Catalog)

WITCHED (A.K.A. DISCRETE OR BINARY) OUTPUT: Most

S sensors are used for presence sensing and offer a relay as an
output switching device. The relay switch is always in either one of
two states: open or closed (ON or OFF).

LECTROMECHANICAL (E/M) RELAYS offer one or more hard

E contacts (metal-to-metal) and are switched to the opened or
closed position by applying voltage to an electromagnetic coil. E/m
relays can switch the highest power levels. They are limited by slow
switching speed and a finite mechanical life.

OLID-STATE RELAYS use switching elements such as transistors

S
Collector

for dc loads and SCRs or FETs for ac loads. Solid-state relays

Base offer fast switching speed and infinite life. They are limited by their
power ratings, and are protected in most sensors against damage
Emitter
from overload by additional circuitry.

674 OUTPUT TYPES Banner Engineering Corp. Minneapolis, U.S.A.

Website: http://www.baneng.com Tel: 612.544.3164
 Understanding Sensing Terms - Performance Specs
XCESS GAIN: Excess gain is a photoelectric sensor specification. It
E is a measurement of the amount of light falling on the receiver over
and above the minimum amount of light required to just operate the
sensors amplifier. Excess gain is plotted versus sensing distance.
Excess gain values are used to predict the reliability of a photoelectric
sensor operating in a known sensing environment (see, below).
1000
SM312DBZ
E SM2A312DBZ
X Diffuse Mode
C
100
E
S
S
Excess Gain Guidelines
G 10
Operating Environment Excess Gain Required
A
I
N CLEAN AIR: No dirt buildup on lenses or reflectors 1.5
1
1 mm 10 mm 100 mm 1000 mm
.04 in .40 in 4.0 in 40 in SLIGHTLY DIRTY: Slight buildup of lint, paper, dust,
DISTANCE
moisture, or film on lenses or reflectors; lenses cleaned 5
regularly
MODERATELY DIRTY: Obvious contamination of lenses
and reflector, but not obscured; lenses cleaned 10
occasionally or when necessary

VERY DIRTY: Heavy contamination of lenses; fog, mist

50 or more
or dust; minimal cleaning of lenses

EAM PATTERN: Beam patterns are two-dimensional plots of sensor

B response versus sensing distance. They can be helpful in predicting
sensor performance. A beam pattern for an opposed mode sensor pair
15 mm
SM312DBZ/SM2A312DBZ 0.6 in
represents the boundary within which the receiver will effectively see
Diffuse Mode
10 mm 0.4 in the emitted light beam, assuming no angular misalignment between
5 mm

0
0.2 in

0
the emitter and receiver. Retroreflective beam patterns are plotted
5 mm 0.2 in using a model BRT-3 retroreflective target. Diffuse and convergent
10 mm
15 mm
0.4 in
0.6 in
mode beam patterns represent the boundary within which the edge of
0 75 mm 150 mm 225 mm 300 mm 375 mm
200 x 250 mm (8 x 10 in) Kodak 90% reflectance white test card is
3.0 in 6.0 in 9.0 in 12.0 in 15.0 in
DISTANCE
detected as it moves into the sensing area. A beam pattern is affected
by many sensing variables, and should be considered as a guideline
and not as an exact specification.

Banner Engineering Corp. Minneapolis, U.S.A.

Website: http://www.baneng.com Tel: 612.544.3164 PERFORMANCE SPECS 675
Understanding Sensing Terms - Environmental Ratings
EtwoNVIRONMENTAL RATING: Banner sensors and modules are rated
for their suitability for use in various sensing environments using
rating systems: National Electrical Manufacturers Association
(NEMA) and The International Electrotechnical Commission (IEC).

NEMA Standards Publication No. 250 guidelines are outlined:

NEMA 1 Indoor Use Protects against accidental contact by personnel & falling dirt
NEMA 2 Indoor Use Protects against falling dirt, liquid & light splash
NEMA 3 Outdoor Use Protects against rain, sleet, snow, dirt & dust
NEMA 3S Outdoor Use Protects against rain, sleet, snow, dirt, dust & ice buildup
NEMA 4 In- or Outdoor Protects against dirt, dust, hosedown (and heavy splash)
NEMA 4X In- or Outdoor Protects against dirt, dust, hosedown & corrosion
NEMA 6 In- or Outdoor Protects against dirt, dust, hosedown & occasional submersion
NEMA 6P In- or Outdoor Protects against dirt, dust, hosedown & prolonged submersion
NEMA 7 Indoor Use For use in areas of explosive gases or vapors or combustible dust
NEMA 9 Indoor Use For use in areas of atmospheres containing combustible dust
NEMA 12 Indoor Use Protects against dirt, dust, light splash & oil or coolant seepage
NEMA 13 Indoor Use Protects against dirt, dust, light splash & oil or coolant spray

The rating system established by IEC Publications 144 and 529 define
the following IP ratings:
1ST CHARACTERISTIC: Protection against contact and penetration of solid bodies
Numeral Short Description
0 Non-protected
1 Protected against solid objects greater than 50 mm
2 Protected against solid objects greater than 12 mm
3 Protected against solid objects greater than 2.5 mm
4 Protected against solid objects greater than 1.0 mm
5 Dust protected
6 Dust-tight
2ND CHARACTERISTIC: Protection against the penetration of liquids
Numeral Short Description
0 Non-protected
1 Protected against dripping water
2 Protected against dripping water when tilted up to 15
3 Protected against spraying water
4 Protected against splashing water
5 Protected against water jets
6 Protected against heavy seas
7 Protected against the effects of immersion
8 Protected against submersion

IuseNTRINSICALLY-SAFE (A.K.A. I.S.) SENSORS: Intrinsic safety is a

design technique applied to electrical equipment, including sensors, for
in hazardous (explosive) locations. The technique involves limiting
KEMA electrical and thermal energy to a level below that required to ignite a
specific hazardous atmosphere. I.S. sensors are used with intrinsic safety
barriers, which are protective components designed to limit the voltage
and current within the hazardous atmosphere. See the SMI912 Series,
page 180 and the SMI30 Series, page 342.

AMUR SENSORS: NAMUR photoelectric sensors are 2-wire devices

N that change their internal resistance relative to the intensity of the
received light. They are designed for use with certified switching
amplifiers with intrinsically-safe circuits, which convert this change to a
binary output signal. NAMUR sensors are most commonly used in
hazardous (explosive) sensing environments. See the Q45AD9 Series,
LISTE D
page 140 and the MIAD9 Series, page 232.

676 ENVIRONMENTAL RATINGS Banner Engineering Corp. Minneapolis, U.S.A.

Website: http://www.baneng.com Tel: 612.544.3164