Banner Q40 User Manual

Q40 Sensors – ac-Voltage Series

P

Self-contained ac-operated sensors

Features

• Featuring EZ-BEAM® technology, the specially designed optics and electronics
provide reliable sensing without the need for adjustments

• Rectangular 40 mm PBT polyester (plastic) housing with 30 mm threaded
mounting base in opposed, retroreflective or fixed-field modes

• Completely epoxy-encapsulated to provide superior durability, even in harsh
sensing environments rated to IP69K

• Innovative dual-indicator system takes the guesswork out of sensor performance
monitoring

• 20 to 250V ac (3-wire hookup); SPST solid-state switch output, maximum
load 300 mA

Models

Sensing Mode Range LED Output Model*

Opposed

Polarized
Retroreflective

Fixed-Field

* Standard 2 m (6.5') cable models are listed.

• 9 m (30') cable: add suffix “W/30” (e.g., Q403E W/30).

• 4-pin Micro-style QD models: add suffix “Q1” (e.g., Q403EQ1). A model with a QD connector requires a mating cable.

60 m (200')

6 m (20')

200 mm (8") cutoff

400 mm (16") cutoff

600 mm (24") cutoff

Infrared
950 nm

Visible Red

680 nm

Infrared
880 nm

–

LO

DO

LO

DO

LO

DO

LO

DO

LO

DO

Q403E

Q40AW3R

Q40RW3R

Q40AW3LP

Q40RW3LP

Q40AW3FF200

Q40RW3FF200

Q40AW3FF400

Q40RW3FF400

Q40AW3FF600

Q40RW3FF600

WARNING . . . Not To Be Used for Personnel Protection

Never use these products as sensing devices for personnel protection. Doing so could lead to serious injury or death.

These sensors do NOT include the self-checking redundant circuitry necessary to allow their use in personnel safety
applications. A sensor failure or malfunction can cause either an energized or de-energized sensor output condition.
Consult your current Banner Safety Products catalog for safety products which meet OSHA, ANSI and IEC standards for
personnel protection.

Printed in USA 01/05 P/N 121515

3ENSING

!XIS

2

2

%

R1

R2

Lenses

Object

A

Object B

or

Background

Sensing

Range

Cutoff

Distance

E

Receiver
Elements

Near

Detector

Far

Detector

Emitter

Object is sensed if amount of light at R1
is greater than the amount of light at R2

Q40 Sensors – ac-Voltage Series

Fixed-Field Mode Overview

Q40 Series self-contained fixed-field sensors are small, powerful, infrared diffuse mode
sensors with far-limit cutoff (a type of background suppression). Their high excess gain
and fixed-field technology allow them to detect objects of low reflectivity, while ignoring
background surfaces.

The cutoff distance is fixed. Backgrounds and background objects must always be placed
beyond the cutoff distance.

Fixed-Field Sensing – Theory of Operation

The Q40FF compares the reflections of its emitted light beam (E) from an object back to the
sensor’s two differently aimed detectors, R1 and R2 (see Figure 1). If the near detector (R1)
light signal is stronger than the far detector (R2) light signal (see object A, closer than the
cutoff distance), the sensor responds to the object. If the far detector (R2) light signal is
stronger than the near detector (R1) light signal (see object B, beyond the cutoff distance),
the sensor ignores the object.

The cutoff distance for model Q40FF sensors is fixed at 200, 400 or 600 millimeters (8",
16", or 24"). Objects lying beyond the cutoff distance are usually ignored, even if they are
highly reflective. However, it is possible to falsely detect a background object, under certain
conditions (see Background Reflectivity and Placement).

Figure 1. Fixed-field concept

In the drawings and discussion on these pages, the letters E, R1, and R2 identify how the
sensor’s three optical elements (Emitter “E”, Near Detector “R1”, and Far Detector “R2”)
line up across the face of the sensor. The location of these elements defines the sensing
axis (see Figure 2). The sensing axis becomes important in certain situations, such as those
illustrated in Figures 5 and 6.

Sensor Setup

Sensing Reliability

For highest sensitivity, the target object should be positioned for sensing at or near the point
of maximum excess gain. The excess gain curves for these products are shown on page 5.
Maximum excess gain for all models occurs at a lens-to-object distance of about 40 mm
(1.5"). Sensing at or near this distance will make maximum use of each sensor’s available
sensing power. The background must be placed beyond the cutoff distance. (Note that the
reflectivity of the background surface also may affect the cutoff distance.) Following these
two guidelines will improve sensing reliability.

Background Reflectivity and Placement

Avoid mirror-like backgrounds that produce specular reflections. False sensor response will
occur if a background surface reflects the sensor’s light more strongly to the near detector,
or “sensing” detector (R1) than to the far detector, or “cutoff” detector (R2). The result
is a false ON condition (Figure 3). To cure this problem, use a diffusely reflective (matte)
background, or angle either the sensor or the background (in any plane) so the background
does not reflect light back to the sensor (see Figure 4). Position the background as far
beyond the cutoff distance as possible.

An object beyond the cutoff distance, either stationary (and when positioned as shown in
Figure 5), or moving past the face of the sensor in a direction perpendicular to the sensing
axis, can cause unwanted triggering of the sensor if more light is reflected to the near
detector than to the far detector. The problem is easily remedied by rotating the sensor
90° (Figure 6). The object then reflects the R1 and R2 fields equally, resulting in no false
triggering. A better solution, if possible, may be to reposition the object or the sensor.

As a general rule, the most reliable
sensing of an object approaching from the
side occurs when the line of approach is
parallel to the sensing axis.

Figure 2. Fixed-field sensing axis

2 P/N 121515

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

www.bannerengineering.com • Tel: [phone]

E

R2

R1

Q40 sensor

E = Emitter

R1 = Near Detector
R2 = Far Detector
Fixed Sensing Field

Strong
Direct
Reflection
to R1

Core of
Emitted

Beam

Cutoff
Distance

Reflective
Background

E = Emitter
R1 = Near Detector
R2 = Far Detector

Reflective

Background

or

Moving Object

E

R2

R1

Q40 sensor

Fixed

Sensing

Field

Cutoff

Distance

E = Emitter
R2 = Far Detector
R1 = Near Detector

E, R2, R1

Q40 sensor

Fixed

Sensing

Field

Cutoff
Distance

Reflective

Background

or

Moving Object

E

R2

R1

Q40 sensor

E = Emitter

R1 = Near Detector
R2 = Far Detector
Fixed Sensing Field

Strong Direct
Reflection
Away
From Sensor

Core of

Beam

Cutoff
Distance

Reflective
Background

Q40 Sensors – ac-Voltage Series

Color Sensitivity

The effects of object reflectivity on cutoff distance, though small, may be important for
some applications. It is expected that at any given cutoff setting, the actual cutoff distance
for lower reflectance targets will be slightly shorter than for higher reflectance targets (see
Figure-of-Merit information on page 5). This behavior is known as color sensitivity.

For example, an excess gain of 1 (see page 5) for an object that reflects 1/10 as much light
as the 90% white card is represented by the horizontal graph line at excess gain = 10. An
object of this reflectivity results in a far limit cutoff of approximately 190 mm (7.5") for the
200 mm (8") cutoff model; thus 190 mm represents the cutoff for this sensor and target.

These excess gain curves were generated using a white test card of 90% reflectance.
Objects with reflectivity of less than 90% reflect less light back to the sensor, and thus
require proportionately more excess gain in order to be sensed with the same reliability as
more reflective objects. When sensing an object of very low reflectivity, it may be especially
important to sense it at or near the distance of maximum excess gain.

Figure 3. Reflective background – problem Figure 4. Reflective background – solution

A reflective background object in this position or
moving across the sensor face in this axis and
direction may cause false sensor response.

A reflective background object in this position or
moving across the sensor face in this axis will be
ignored.

Figure 5. Object beyond cutoff – problem Figure 6. Object beyond cutoff – solution

P/N 121515 3

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

www.bannerengineering.com • Tel: [phone]