S18UBA BANNER ENGINEERING, S18UBA Datasheet - Page 2
![Ultrasonic Sensor](/photos/20/10/201082/4608903_sml.jpg)
S18UBA
Manufacturer Part Number
S18UBA
Description
Ultrasonic Sensor
Manufacturer
BANNER ENGINEERING
Type
Ultrasonicr
Specifications of S18UBA
Sensing Range Min
30mm
Sensing Range Max
300mm
Switching Frequency
300kHz
External Diameter
18mm
Operating Temperature Range
-20°C To +60°C
Supply Voltage
30VDC
Frequency
300kHz
Body Style
Cylindrical
Brand/series
S18U
Current, Switching
100 mA
Function
Proximity
Ip Rating
IP67
Mounting Type
Threaded
Output
NPN/PNP, SPST
Primary Type
Proximity
Range, Measurement
300 mm
Technology
Ultrasonic
Termination
Cable
Voltage, Supply
30 VDC
Accessories Available
Cordsets, Brackets and Waveguides
Body Material
Thermoplastic Polyester
Contact Rating
65 MA
Lead Free Status / Rohs Status
RoHS Exempt Product
Ultrasonic sensors emit one or multiple pulses of ultrasonic energy, which travel
through the air at the speed of sound. A portion of this energy reflects off the target
and travels back to the sensor. The sensor measures the total time required for the
energy to reach the target and return to the sensor. The distance to the object is then
calculated using the following formula:
To improve accuracy, an ultrasonic sensor may average the results of several pulses
before outputting a new value.
The speed of sound is dependent upon the composition, pressure and temperature of
the gas in which it is traveling. For most ultrasonic applications, the composition and
pressure of the gas are relatively fixed, while the temperature may fluctuate.
In air, the speed of sound varies with temperature according to the following
approximation:
Or, in English units:
Temperature Compensation
Changes in air temperature affect the speed of sound, which in turn affects the distance
reading measured by the sensor. An increase in air temperature shifts both sensing
window limits closer to the sensor. Conversely, a decrease in air temperature shifts
both limits farther away from the sensor. This shift is approximately 3.5% of the limit
distance for a 20° C change in temperature.
The S18U series ultrasonic sensors are temperature compensated. This reduces the
error due to temperature by about 90%. The sensor will maintain its window limits to
within 1.8% over the -20° to +60° C range.
NOTES:
• Exposure to direct sunlight can affect the sensor’s ability to accurately compensate for
• If the sensor is measuring across a temperature gradient, the compensation will be
• The temperature warmup drift upon power-up is less than 1.7% of the sensing
U-GAGE
2
changes in temperature.
less effective.
distance. After 10 minutes, the apparent distance will be within 0.3% of the actual
position. After 25 minutes, the sensing distance will be stable.
P/N 108964 rev. A
C
C
m/s
ft/s
™
= 49 √460 + T
= 20 √273 + T
S18U Series Sensor — Discrete Output
D =
Principles of Operation
F
C
Temperature Effects
ct
2
C
T
C
T
C
m/s
F
ft/s
D = distance from the sensor to the target
c = speed of sound in air
t = transit time for the ultrasonic pulse
= temperature in °C
= temperature in °F
= speed of sound in feet per second
= speed of sound in meters per second
Banner Engineering Corp.
www.bannerengineering.com • Tel: 763.544.3164
•
Minneapolis, MN U.S.A.