MQ-W
SERIES
Triple Beam Trigonometric
Area Reflective Photoelectric Sensors
Very accurate detection by triple beam triangulation sensing method in a compact package.
Environmental resistance
Immersion protected construction
(equivalent to IEC IP67)
High speed detection: Max. 2 ms
Light-ON/Dark-ON output is wire
selectable.
Operating voltage of 12 to 24 V DC
Adjuster and Indicators
Distance adjustment dial
(Comply with EMC directive MQ-W-EM type only)
* Original
MQ-W3 type
MW-W20 type
Sensor
Operation
Indicator LED
Distance adjustment dial
FEATURES
Accurate detection regardless of
color, material, or shape of objects
Area reflective type sensor can detect
white or black object at the same distance. In case of diffuse reflective type,
it is difficult to detect objects of various
color with the same sensitivity setting.
MQ-W area reflective type sensor is
useful for such a case.
No-miss operation regardless of
back-grounds
Area reflective type sensor does not
detect objects beyond the set range.
Resistant to lens surface soiling
Area reflective type sensor detects the
distance by the angle, not the intensity
of received light. Even if the lens surface is soiled by dust or any powdery
material, there is a little variation of
sensing range.
MQ-W70 type
Adjustment
indicator LED
Adjustment
indicator LED
Operation
Indicator LED
SENSING RANGES
Sensing range (m ft.)
0.03 .098
0.2 .656
0.7 2.297
MQ-W3 types
MQ-W20 types
MQ-W70 types
PRODUCT TYPE
Detection method
Range
Rated operating voltage Control output
NPN
0.03 m .098 ft.
PNP
Triple beam area
reflective type
12 to 24 V DC
NPN
0.2 m .656 ft.
PNP
0.7 m 2.297 ft.
NPN
PNP
Light source
Part number
*1 CE types
Infrared LED
MQ-W3A-DC12-24V
MQ-W3A-DC12-24VEM
Red LED
MQ-W3AR-DC12-24V
MQ-W3AR-DC12-24VEM
Infrared LED
MQ-W3C-DC12-24V
MQ-W3C-DC12-24VEM
Red LED
MQ-W3CR-DC12-24V
MQ-W3CR-DC12-24VEM
MQ-W20A-DC12-24V
MQ-W20A-DC12-24VEM
Infrared LED
Red LED
Infrared LED
Red LED
Infrared LED
MQ-W20AR-DC12-24V MQ-W20AR-DC12-24VEM
MQ-W20C-DC12-24V
MQ-W70A-DC12-24V
MQ-W70A-DC12-24VEM
MQ-W70C-DC12-24V
MQ-W70C-DC12-24VEM
*1 These suffix EM types conform to CE. These types have the grounding connection inside of housing
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03/2003
MQ-W20C-DC12-24VEM
MQ-W20CR-DC12-24V MQ-W20CR-DC12-24VEM
MQ-W
SPECIFICATIONS
1) Ratings
12 to 24 V DC
Rated operating voltage
Operating side
Rated current consumption
Load side
30 mA or less (excluding load)
100 mA or less
Output current capacity
2) Performance
Detection principle
Triple beam triangulation sensing method
Detection method
Area reflective type
Type
Amplifier selfcontained DC type
MQ-W3A-DC12-24V
MQ-W3AR-DC12-24V
MQ-W3C-DC12-24V
MQ-W3CR-DC12-24V
Part number
Sensing range
Detectable distance
Standard target
MQ-W20A-DC12-24V
MQ-W20AR-DC12-24V
MQ-W20C-DC12-24V
MQ-W20CR-DC12-24V
MQ-W70A-DC12-24V
MQ-W70C-DC12-24V
0.03 m .098 ft.
0.2 m .656 ft.
0.7 m 2.297 ft.
0.02 to 0.04 m .066 to .131 ft.
0.04 to 0.2 m .131 to .656 ft.
0.2 to 0.7 m .656 to 2.297 ft.
White drawing paper
11 cm .394.394 inch
White drawing paper
22 cm .787.787 inch
White drawing paper
7.57.5 cm 2.9532.953 inch
Detectable target
Opaque, translucent
Hysteresis
10% or less the set range
Operating voltage range
Response time (freq.)
Initial insulation resistance
Initial breakdown voltage
Vibration resistance
Shock resistance
9.6 to 30 V DC ripple (P-P) included
2 ms or less (250 times per second or less)
Min. 20 MΩ between a lead wire and external housing (at 500 V DC)
Between a lead wire and external housing: 500 Vrms for 1 min
10 to 55 Hz (1 cycle/min), double amplitude 1.5 mm .059 inch (2 h each on 3 axes)
980 m/s2 {approx. 100 G} (6 times each on 3 axes)
Protective construction
Usable ambient
light level
20% or less of the set range
Diecast case immersion protected (equivalent to IEC IP67)
Incandescent lamp
10,000 lux or less
Sunlight
30,000 lux or less
Ambient temperature
Ambient humidity
–25 to 55°C –13 to +131°F (non-icing condition)
Max. 85% RH (non-condensing condition)
Storage temperature
Indicator
Light source
–25 to 55°C –13 to +131°F
Operation indicator: Red LED ON with light entry
Adjustment indicator: Red LED ON with sufficient volume of lights
Infrared LED/Red LED (R is added to the suffix of W3(20)A(C) in the part No.)
Note: Unless otherwise specified, the measurement conditions comprise rated operating voltage, power supply by battery, 20°C 68°F ambient
temperature, standard target and 200 lux or less illuminance on the receiver surface.
3) Output circuit diagram
NPN Output type
PNP Output type
03/2003
181
MQ-W
DATA
1. Operating range characteristics
30
.098
20
.066
For 40 mm .131 ft.
Moving direction
Standard target
(white drawing paper
10×10 mm .394×.394 inch)
For 30 mm .098 ft.
For 20 mm .066 ft.
Operating
distance (mm)
(ft.)
40
.131
MQ-W70 types
Operating
distance (mm)
(ft.)
MQ-W20 types
Operating
distance
(mm)
(ft.)
MQ-W3 types
200 For 200 mm .656 ft.
.656
600
1.969
150 For 150 mm .492 ft.
.492 Moving direction
Standard target
(white drawing paper 20×
100
20 mm .787×.787 inch)
.328
For 100 mm .328 ft.
400
1.312
200
.656
50
.164 For 50 mm .164 ft.
10
10
.394 5 0 5 .394
.197
.197 Operating range (mm)
(inch)
10
10
.394 5 0 5 .394
.197
.197 Operating range (mm)
(inch)
For 700 mm 2.297 ft.
For 500 mm 1.641 ft.
Moving direction
Standard target
(white drawing paper 75×
75 mm 2.953×2.953 inch)
For 300 mm .984 ft.
10
10
.394 5 0 5 .394
.197
.197
Operating range (mm)
(inch)
2. Projector beam diameter characteristics
Light beam diameter is determined as the region where the amount of light is decreased to 1/e2 (e]2.72) when the largest amount of light is
assumed as 1.
MQ-W3 types
MQ-W20 types
MQ-W70 types
2.5 dia. 2.3 dia. 4.0 dia. (mm
.098
.091
.157
inch)
0
0
20
.066
30
.098
23.0 dia. 33.0 dia. 39.0 dia. (mm
.906
1.299
1.535
inch)
6.7 dia. 6.9 dia. 7.4 dia. 8.3 dia. (mm
.264
.272
.291
.327
inch)
50
.164
40 (mm ft.)
.131
100
.328
150
.492
200 (mm ft.)
.656
0
300
.989
500
1.641
700 (mm ft.)
2.287
3 Detectable target characteristics
MQ-W20 types
Standard target
(white drawing paper 10×10 mm
.394×.394 inch)
Distance setting 30 mm
.098 ft.
30
.098
MQ-W70 types
700
2.297
200
.656
Distance setting 200 mm
.656 ft.
Standard target
(white drawing paper 20×20 mm
.787×.787 inch)
Distance setting 100 mm
.328 ft.
100
.328
0
Distance setting 40 mm
.131 ft.
0
100
10
0.155
0.015
Target size (mm2 inch2)
600
1.969
Distance setting 700 mm
2.297 ft.
Standard target
(white drawing paper 75×75 mm
2.953×2.953 inch)
500
1.641
Distance setting 400 mm
1.312 ft.
400
1.312
300
.984
Distance setting 200 mm
.656 ft.
200
.656
Distance setting 20 mm
.066 ft.
20
.066
Distance range (mm ft.)
Distance setting 40 mm
.131 ft.
40
.131
Distance range (mm ft.)
Distance range (mm ft.)
MQ-W3 types
100
.328
0
100
1000
0.155
1.55
Target size (mm2 inch2)
1,000
1.55
10,000
15.5
Target size (mm2 inch2)
4. Material characteristics
Former pruduct
Corrugated
carton
Triple beam type (MQ-W20A)
Veneer panel
Black rubber
Black frosted
finish
Copper clad
printed circuit
board
×
×
Aluminum
panel
Mirror
100
200
300
400
500
600
.328 .656 .984 1.132 1.641 1.969
Distance range (mm ft.) × : Impossible
182
White
drawing
paper
MQ-W20 types
Condition: Target (4060 mm 1.5752.362
inch), natural shape
Glossy target Semi-glossy target Non-glossy target
White drawing
paper
MQ-W3 types
Condition: Target (4060 mm 1.5752.362
inch), natural shape
Glossy target Semi-glossy target Non-glossy target
Comparision between MQ-W20A and former product
Condition: Target (4060 mm 1.5752.362 inch),
target assumed as natural shape
For the former product (diffuse reflective type),
depending upon the object material, the operating
range varied greatly, but for the triple beam type
there a little variation.
Black
drawing
paper
Veneer panel
Corrugated
paper
Black rubber
Copper clad
printed circuit
board
White acrylic
Blue acrylic
Mirror
10
.033
20
.066
30
.098
Distance range (mm ft.)
03/2003
40
.131
White
drawing
paper
Black
drawing
paper
Veneer panel
Corrugated
paper
Black rubber
Copper clad
printed circuit
board
White acrylic
Blue acrylic
Mirror
50
100
150
.164
.328
.492
Distance range (mm ft.)
200
.656
MQ-W
DIMENSIONS
Outline dimensions
mm inch
1. MQ-W3 types
Dimensions with the mounting bracket**
attached
Adjustment indicator LED
12.6 12.2
.496 .480
4.2 DIA.
.165
4.4
Distance adjustment dial
Operation indicator LED
.173
3.3
3.3
.130 25.4±0.2 .130
2-M4 (P = 0.6) tapped
1 inch
1
M.S.:* M4 or #6
6.3 .039
.248
32
1.260
25.4±0.2
1 inch
6.3
.248
11.7
.461
3.3
.130
0
00 4
2, 8.7
7
2. MQ-W20 types
12.6 12.2
.496 .480
2.2
.087
6.3
.248
4.4
24.4 .173
(1 inch)
44.8
1.764
24
.945
10.9
.429
4
.157 1.4
.055
4.2 DIA.
.165
Distance adjustment dial
Operation indicator LED
(17)
10.7 (.669)
.421
4.4
.173
3.3
25.4±0.2 .130 2-M4 (P = 0.6) tapped
1 inch
M.S.:* M4 or #6
7.3
.287
2.2
.087
6.3
.248
4.4
24.4 .173
(1 inch)
7.5
.295
25.4±0.2
7.5
1 inch
.295 32
1.260
10.5
.413
3.3
.130
44.8
1.764
24
.945
10.9
.429
0
00 4
2, 8.7
7
3. MQ-W70 types
Outline dimensions
4
.157 1.4
.055
General tolerance:
±0.5 .020
Dimensions with the mounting bracket**
attached
4.2 DIA.
.165
Distance adjustment dial
1
.039
4 16.6
.654
.157
25.4
1 inch
Adjustment indicator LED
18.6 18.2
.732 .717
3.5
.138
General tolerance:
±0.5 .020
Dimensions with the mounting bracket**
attached
Adjustment indicator LED
1
.039
7.3
.287
4 16.6
.157 .654
25.4
1 inch
Outline dimensions
3.3
.130
(17)
10.7 (.669)
.421
45±0.2
1-49/64
Operation indicator LED
3.5
.138
4.4
.173
2-M4 (P = 0.6) tapped
M.S.:* M4 or #6
13
.512
45.0
1.772
(22)
12.7 (.866)
.500
4
.157
4.4
4.5 DIA.
.177
.173
9.1
8.1
44
.358
.319
(1-3/4 inch)
52
13 2.047 45±0.2
1-49/64
.512
15.5
.610
12.5
.492
68.2
12.52.685
.492
3.5
.138
0
00 4
2, 8.7
7
24
12.4 .945
.488
17.4
.685
36.6
1.441
45
1-49/64
*M.S.: mounting screw
1.6
.063
General tolerance:
±0.5 .020
**The mounting bracket is enclosed in the inner carton.
CONNECTING DIAGRAM
Make connection to B side with pink wire for
Light ON
Make connection to v side with pink wire for
Dark ON
Note: When switching a power source, make
ground connection to the frame ground terminal or to the ground terminal. This will assure
more stable operation.
03/2003
Operating condition
Output transistor
With light
intercepted ON
Common use
With light
entering ON
Operation
indicator LED
Lights with light entering
183
MQ-W
OPERATING PRINCIPLES
Detection principle of new triple beam area reflective series
$ Optical triangulation sensing method
The light beam projected by the LED,
passing through the condensing lens of
the light projector, is applied to the surface of the target to be detected. One
part of the diffused reflected light rays
passes through the light receiver lens
producing a spot on the position sensitive device. When the detectable target
is at a position A that is at a compara-
tively near distance as shown in Fig. 1,
a spot is produced at (a). When the target is at a position B that is far, a spot
is produced at (b). Accordingly, if any
spot position on the position sensitive
device is detected, the distance to the
target can be determined. This is the
principle of optical triangulation range
measurement.
Fig. 1 Optical triangulation range
measurement method
Other examples of this method are
the automatic focusing and camera
range measurement systems.
$ Triple beam type range sensing principle
The MQ photoelectric sensor area
reflective type has adapted this optical
triangulation range measurement principle, but in order to improve the reliability of the detection of the sensor, a
more elaborate method has been
devised. First, light receivers are positioned symmetrically on either side of
the axis of the light projector, composing a triple beam arrangement. As
shown in Fig. 2, when the moving
detectable target is at the edge of the
projected light beam, the spot reflected
from the target is at a location different
from the point where the spot is produced when the beam is completely
intercepted, generating a range measurement difference of +∆X, but with
the triple beam composition, the symmetrically arranged position sensitive
device (2) has a spot produced conversely at a –∆X difference position,
and by means of averaging both range
measurement signals, the correct range
measurement can be made. This
results in significantly improved
repeatability and background suppression.
Fig. 2 Triple beam range measurement method
By averaging the range measurement signals of the 2 light receiving
systems, the range measurement
difference is cancelled.
$ Optical system of the triple beam photoelectric sensor
In the MQ photoelectric sensor area
reflective type, it is necessary to give
special consideration to the lens. In
order to improve the precision, an
aspherical lens, having limited spherical
and coma aberration, is used.
In addition, as shown in Fig. 4, a photo
diode having 2 output terminals is used.
By comparing the output currents from
the 2 PSDs, there is no relationship to
the level of the incident light. Thus, the
ratio of reflection from the detectable
target exerts no influence and the
range measurement and detection can
be interpreted accuracy.
Fig. 3 Light beam trace of the lens
(a) is a spherical lens, and (b) is the
aspherical lens. Because there is no
aberration in (b), range measurement precision is high.
Fig. 4 PSD (position sensitive
device) construction
By making a calculation of the ratio
of I1 and I2, the light spot position
can be detected.
$ Operating principle of area reflective method
The operation of the MQ photoelectric
sensor area reflective type is explained
in Fig. 5. After the output from the 2
PSD elements is added, the I/V value is
converted and the logarithm determined. By subtraction, the distance signal in (I1/I2) is obtained. This can be
optionally set, and with the distance
adjustment control, comparison with the
produced value can be made to detect
whether the target is or is not within the
distance range.
Fig. 5 Signal processing circuit block diagram
184
03/2003
MQ-W
CAUTIONS
These products are not
safety sensors and are
not designed or intended
to be used to protect life
and prevent bodily injury
or property damage.
1. Ambient environment
1) Use within the range of ambient
temperature of –25 to +55°C –13 to
+131°F.
2) Use within a range of 9.6 V to 30 V
DC (ripple P-P included) for operating
voltage.
3) Use with an ambient light level at the
light receiving surface of less than
10,000 lux for incandescent lamp and
less than 30,000 lux for sunlight.
4) Use a surge absorber as the internal
circuit may be damaged if external
surge voltage exceeds 500 V
[±(1.250) µs of single polarity fullwave voltage].
5) Avoid using in a location with high
concentrations of steam, dust, or corrosive gas.
6) The sensor is of immersion protected
type, but this does not mean that it can
be used in water or where there is
direct impingement of rain for detecting
objects.
2. Connections
1) Check all wiring before applying
power since incorrect wiring may damage the internal circuit.
2) Use a load relay with a rated operating voltage of 12 V DC or 24 V DC. The
voltage applied to the load relay is the
operating voltage of the photoelectric
sensor minus the internal voltage drop
(1.2 V). Voltage fluctuations should be
taken into account.
3) If a load greater than 100 mA is connected, the output section will be
damaged, so sufficient care should be
taken.
4) If the wiring to the photoelectric sensors run parallel to high voltage or
power lines, due to inductive noise,
mis-operation or damage can occur.
Wiring should be run in separate.
5) Wire 0.3 mm2 .0005 inch2 AWG22 or
larger should be used for wiring up to a
length of 100 m 328 ft..
6) When the photoelectric sensors
being mounted, if the unit is struck by a
hammer or other heavy tool, the function can be impaired. Sufficient care
should be taken.
7) The changeover from Light-ON (light
entry ON) to Dark-ON (light intercepted
OFF) can be carried out with the pink
lead wire. For Light-ON, connect the
pink wire to the B side, and for DarkON, connect the pink wire to the v
side.
3. Distance adjustment
1) Set the detecting surface of the photoelectric sensor in the detecting direction and temporarily fasten it.
2) While no target in the detection
region, set the distance adjustment dial
to maximum (FAR) and slowly turn it
counterclockwise.
Continue turning the control counterclockwise until the operation indicator
LED (OPE.) is extinguished. This is the
adjustment position. If the indicator
LED is extinguished at the maximum
position, that is the adjustment position.
3) With target in the detection area, set
the dial in the minimum position
(NEAR) and turn the control clockwise
to locate the position where the indicator LED turns ON. If the indicator LED
goes ON at the minimum position, then
NEAR is the adjustment position.
4) Set the control to a point midway
between the locations found in 2) and
3) above.
5) Securely fasten the photoelectric
sensor. When fastening, the sensor
should be sufficiently secure so that it
will not shift under vibration of shock.
03/2003
Distance adjustment dial
MQ-W3 type
MW-W20 type
Distance adjustment dial
MQ-W70 type
Adjustment
indicator LED
Operation
Indicator LED
Adjustment
indicator LED
Operation
Indicator LED
Notes:
1. If the adjustment indicator LED does
not light in the adjustment of 3) as prescribed, or if the position between 2)
and 3) is less than 2 graduations,
change the position of the detection
surface and repeat the procedure of 1)
to 4), or try to determine the source of
external factors such as variation in
ambient temperature, variation in target
position, etc., that creating the problem.
2. The difference in detection distance
due to the colors of the target is virtually non-existent, but if the actual target is
one where the reflectivity is extremely
low (target which have a frosted finish
produced by black rubber), or where
the reflectivity is extremely high (mirror,
glass, or truly reflectting target), confirmation should be done with the actual
target.
4. Detector
1) Keep the detector surface clean as
excessive dust or dirt on the detector
surface will decrease the margin of the
distance range.
2) The front surface of the lens is made
of polycarbonate. This material is resistant to water, weak acids and alkalis,
aliphatic hydrocarbons, oils, etc., but it
is not resistant to ketones, esters, halogenated hydrocarbons, or aromatic
hydrocarbons.
185