Ultrasonic Long Range E4A-3K
Long Sensing Distance of 0.3 to 3 m
Background suppression for accurate
sensing
Fast alignment troubleshooting with
stable operation check function
Mutual interference protection built in
Self-contained, no external power
supply required
Ordering Information
Supply voltage Sensing type Sensing distance Part number
12 to 24 VDC Reflective 0.3 to 3 m E4A-3K DC12/24
120/240 VAC E4A-3K AC120/240
100/200 VAC E4A-3K
Specifications
RATINGS/CHARACTERISTICS
Part number E4A-3K DC12/24 E4A-3K AC120/240 E4A-3K AC100/200
Sensing method Reflective
Supply voltage 12-24 VDC, 10% ripple
(p-p) 10% 120/240 VAC, 50/60 Hz,
10% 100/200 VAC, 50/60 Hz,
10%
Power consumption 150 mA max. Approx. 2.5 VA Approx. 2.5 VA
Sensing distance Adjustable between 0.3 and 3 m (selectable ranges of 0.3 to 2 m and 1.3 to 3 m)
Standard sensing object 100 mm dia., 1.5 m long metal or plastic round pipe
Minimum sensing object 50 x 50 mm flat plate
Directional angle 25°
Ultrasonic oscillation frequency Approx. 40 kHz
Response time Operate 0.25 s
Release 0.5 s
Control output Contact output : SPDT
3 A at 220 VAC/24 VDC (resistive load)
Indicators Operation, red LED
Ambient operating temperature –20°C to 55°C (–4°F to 131°F) with no icing
Relative humidity 45% to 85%
(This table continues on the next page.)
E4A-3K
E4A-3K
2
Specifications Table – continued from previous page
Part number E4A-3K DC12/24 E4A-3K AC120/240 E4A-3K AC100/200
Insulation resistance 20 MΩ minimum at 500 VDC
Dielectric strength 1500 VAC, 50/60 Hz for 1 minute
Vibration resistance 10 to 25 Hz, 1.5-mm double amplitude for 2 hours each in X, Y and Z axes
Shock resistance 500 m/s2 (approx. 50 g) 6 times each in X, Y and Z axes
Life expectance
(ttl)
Mechanical 20,000,000 operations minimum
(output relay) Electrical 100,000 operations minimum
Enclosure rating IP60
Approvals UL, cUL Recognized, File No. E41515
Weight Approx. 600 g with mounting bracket
Approx. 500 g without mounting bracket
OPERATING RANGE AND SENSING ZONE
1. Distance Selector Set to a Range Between
0.3 and 2 m 2. Distance Selector Set to a Range Between
1.3 and 3 m
Sensor
Reference level
A: Sensing distance
The sensing distance (A) is adjust-
able with the distance selector to a
range between 0.3 and 2 m.
If the sensing distance (A) is set to 2 m,
the sensing zone (B) is 1.5 to 2 m.
If the sensing distance (A) is set to 0.3 m,
the sensing zone (B) is 0 to 0.3 m.
The distance from the reference level to the operating range (sensing zone).
Sensor
Reference level
A: Sensing distance
The sensing distance (A) is adjust-
able with the distance selector to a
range between 1.3 and 3 m.
Blind zone
If the sensing distance (A) is set to 3 m,
the sensing zone (B) is 1.5 to 3 m.
If the sensing distance (A) is set to 1.3 m,
the sensing zone (B) is 0 to 1.3 m.
Sensing zone (B) 1.5 m
The distance from the reference level to the operating range (sensing zone).
B: Sensing zone
Sensing zone (B) 0.5m
An object may be detected due to multiple reflection if the object is in the blind zone, in which case the detection of the object will not be
stable. Therefore, do not attempt to use the E4A-3K to detect an object in the dead range by making use of multiple reflection.
Note: Multiple reflection is a phenomenon caused by an ultrasonic beam reflected several times repeatedly between the sensing object
and the Sensor or nearby objects such as the ceiling.
E4A-3K E4A-3K
3
En
g
ineerin
g
Data
OPERATING ZONE (TYPICAL EXAMPLES)
The operating zone is the sensing range of the E4A-3K at the sensing distance with the sensing object moved vertically towards the ultra-
sonic beam. The operating zone varies with the sensing distance and sensing object.
Distance (cm) Distance (cm)
Operating
zone (cm) Ultrasonic
sensor Operating
zone (cm) Operating
zone (cm) Ultrasonic
sensor Operating
zone (cm)
Distance (cm)
Sensing object :
25 dia. x 100 (mm)
Operating
zone (cm) Ultrasonic
sensor Operating
zone (cm)
Sensing object:
200 x 200 (mm)
flat plate
Sensing object :
100 dia. x 1,000 (mm)
•If more than one Unit is used within a maximum distance of
8m, be sure to wire the sensor for synchronous operation.
Refer to
External Connections
for details.
8 m max.
•If there is a door between two Units located for different oper-
ating zones as shown in the following illustration, be sure to
wire the Units for synchronous operation, or interference may
occur when the door opens.
Sensor
Door
E4A-3K
E4A-3K
4
Dimensions
Unit: mm (inch)
E4A-3K
Rubber cap
Indicator
Mounting Holes
Two, 6.5 dia.
6.6 dia.
24 dia.
3
92 104
(4.09)
29 23
130
(5.12)
50
(1.97)
40
(1.57)
4
32.5
40
150
105
118
159 (6.26)
40
22
17
56
6.6 8
E4A-3K E4A-3K
5
Installation
EXTERNAL CONNECTIONS
Example of Connections of the
E4A-3K in Asynchronous Operation Example of Connections of the E4A-3K in Synchronous Operation
Note: 1. If the synchronous operation of the
E4A-3K is not required, set the ref-
erence pulse selector to ON. Keep
terminals 7 and 8 open.
2. Use a cable with an external diam-
eter of 10 mm max. for wiring.
Note: 1. If the synchronous operation of the E4A-3K is required, set the reference
pulse selector of only one Unit to ON. Then connect terminal 7 of all the
Units together and do the same for terminal 8.
2. A maximum of 50 sensors can be connected in synchronous operation.
3. Do not wire the lines for synchronous operation use (i.e., wires connect-
ing to terminals 7 and 8) alongside power lines in the same conduit.
4. Use a shielded cable with an external diameter of 10 mm max. for wiring.
5. Make sure that all the Units in synchronous operation are turned on,
otherwise none of the Units will operate.
Contact output
100/120 VAC
200/240 VAC
Contact output Contact output
+– Tc Ta Tb
12~24 VDC
ON
OFF
Tc TbTa Tc TbTa
+–
12~24 VDC +–
12~24 VDC
100/120 VAC
200/240 VAC
100/120 VAC
200/240 VAC
ON
OFF
ON
OFF
Adjustments
REFERENCE PULSE SELECTOR
POSITION
If more than one Unit is used at one location, the Units will need
to be in synchronous operation to prevent mutual interference. In
that case, set the reference pulse selector of only one Unit to ON.
Set the reference pulse selector of each Unit to ON if the Units
are in asynchronous operation. Refer to
External Connections
for
details.
Operation indicator
Sensing distance adjuster
Distance selector
Reference pulse selector
SENSING DISTANCE ADJUSTMENTS
Before adjusting the sensing distance, remove the rubber cap
from the top of the E4A-3K. Be sure to put on the rubber cap
after the sensing distance is adjusted.
1. Apply a flat-blade screwdriver to the groove of the distance
selector to set the distance selector to either a range be-
tween 0.3 and 2 m or a range between 1.3 and 3 m accord-
ing to the desired sensing distance and operating range.
2. To set the sensing distance, first locate a flat plate as a sens-
ing object that is approximately 20-by-20 cm at the desired
sensing distance. Then gradually turn the sensing distance
adjuster clockwise (i.e., in the direction increasing the sens-
ing distance) until the relay operates. The operation indicator
will be lit when the relay operates.
E4A-3K
E4A-3K
6
STANDARD SENSING DISTANCE
SETTINGS
•If the sensing object is moving across the ultrasonic beam
(i.e., the E4A-3K is in normal sensing operation), set the
sensing distance so that the sensing side of the object
passes through the center of the operating range as shown in
the following illustration.
Sensing distance
Operating range
Sensing side
d
If there is an object, such as a floor, wall, or conveyor, located
behind the sensing object, make sure that the distance between
the set sensing distance (d) and the background object is 0.1d
min. Also, make sure that the set sensing distance (d) is at least
0.1d closer to the Sensor from the maximum limit of the operating
range as shown in the following illustration.
Operating range
Sensing side
0.1 d min.
0.1 d min.
Sensing distance
d
From the above, the minimum height (h) of the sensing object is
expressed by 0.2d. If the sensing object is comparatively low in
height or if the E4A-3K is used for the delicate height
discrimination of objects, it will be necessary to set the sensing
distance to a small value.
•If the sensing object is moving parallel to the ultrasonic beam
for level or height detection, the sensing distance will be the
distance required for the sensing object to move.
Sensing distance
Operating range
d
OPERATION CHECK
After adjusting the sensing distance, check that the E4A-3K
operates properly by locating the sensing object within the
operating range. Then remove the sensing object and check that
the operation indicator is not lit. The operation indicator may be
still be lit or flashing after the sensing object is removed. In that
case, the E4A-3K may be malfunctioning due to beam reflection
from objects outside the operating range or affected by ambient
wind or temperature, in which case, eliminate the cause or
change the mounting position or direction of the Sensor.
If the mounting position or direction of the Sensor is changed, be
sure to check the sensing distance and the operation of the
E4A-3K.
Operation indicator flashing Operation indicator not lit
E4A-3K E4A-3K
Precautions
SENSOR MOUNTING ANGLE
If the E4A-3K is in level control or distance control of sensing
objects, the stability of signal detection will depend on the
sensing surface condition of the objects. Considering the repose
angle of the objects, mount the E4A-3K so that the ultrasonic
beam and the sensing surface of each object meet at right angles
to each other.
SURROUNDING OBJECTS
Make sure that the Sensor is free from surrounding objects that
reflect the ultrasonic beam diffusion, otherwise the Sensor may
malfunction. In particular, pay the utmost attention so that no
peripheral area of the ultrasonic beam will be reflected by such
objects.
MOUNTING
Securely mount the E4A-3K by using the nuts provided with the
E4A-3K or the mounting holes of the E4A-3K. Refer to
Dimensions
for details.
Do not subject the Sensor to heavy impact, shock, or vibration
(see
Specifications
) or the E4A-3K will no longer be
water-resistant.
If the E4A-3K is not mounted securely, it may be damaged by
vibration or may not detect sensing objects accurately due to a
possible change in the mounting position.
ENVIRONMENTAL CONDITIONS
Do not use the E4A-3K at a temperature exceeding the rated
range or outdoors, otherwise the reliability and life of the E4A-3K
will decrease.
The Ultrasonic Sensor utilizes the air as a beam transmission
media. Do not use the E4A-3K in places with strong air currents
or extreme temperature changes. For example, if there is an air
curtain that causes turbulence within the sensing area, the
E4A-3K may malfunction.
Turbulence Air curtain
E4A-3K
The jetting sound of air nozzles includes noise of a wide
frequency range, which will affect the operation of the E4A-3K.
Do not use an air nozzle near the E4A-3K.
The sensing distance of the E4A-3K will decrease if there is any
water drops on the surface of the emitter or receiver.
The reflective model may not detect any objects if there is any
object absorbing sound, such as powder and cotton, on the
surface of the emitter or receiver.
Cat. No. CEDSAX3 10/99 Specifications subject to change without notice. Printed in U.S.A.
OMRON ELECTRONICS, INC.
One East Commerce Drive
Schaumburg, IL 60173
NOTE: DIMENSIONS SHOWN ARE IN MILLIMETERS. To convert millimeters to inches divide by 25.4.
1-800-55-OMRON
OMRON CANADA, INC.
885 Milner Avenue
Scarborough, Ontario M1B 5V8
416-286-6465
