For oil transporter tank or big tank fuel monitoring, ultrasonic liquid level sensor is needed. Compared to voltage or pressure level sensor, ultrasonic fuel sensor is more accurate and easy to install. Uniguard Technology Limited offers complete fuel monitoring and fuel tracking solutions with GPS Tracker Model UT04.

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Ultrasonic Liquid Level Sensor
For oil transporter tank or big tank fuel monitoring, ultrasonic liquid level sensor is needed. Compared to
voltage or pressure level sensor, ultrasonic fuel sensor is more accurate and easy to install. Uniguard
Technology Limited offers complete fuel monitoring and fuel tracking solutions with GPS Tracker Model
UT04.
1. Introduction
The imported non-contact ultrasonic sensor technology is used. Ultrasonic sensor is widely used in
measurement of distance, depth, displacement, liquid level, material level and transparent objects. By
connecting with GPS tracking device, it can be used to monitor fuel consumption details.
2. Product details
2.1Components
Ultrasonic liquid level sensor is composed of ultrasonic sensor and signal control box.
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2.2Specifications
Working Voltage: 9-36V DC 50mA
Max Power 0.8W/12VDC
Working Temperature -40℃－+85℃
Measurement Range 5cm-99cm (customize MAX 2.5M)
Pressure Range <=0.8KG or 0.8MPa
Level Height Accuracy 5%
Protection Level Sensor Head IP66, Signal control box IP61
Working Environment Moisture-proof(detector),acid-proof(detector),anti-interference,anti-expl
osion(detector), flame retardant(detector), anti-seismic(detector)
Anti-explosion Rate Intrinsic Safety Exia Ⅱ CT6; flameproof Exd Ⅱ CT5
Device interface This device provides a voltage analogue output port, RS232 data port.
Voltage sampling port Output voltage range: 0-5V. Computational formula for actual liquid level
and voltage output. 5V output means maximum level height.
RS232 port the default baud rate 9600, each 10S interval sensors measured fluid level
in real time (unit 0.1mm), temperature (unit 0.1℃). Baud rate according to
user needs to modify, and transmit data time interval.
Connection Yellow wire: connect RS232 output port of gps tracker; Blue wire: connect
RS232 input port of gps tracker; Green wire: connect analog wire of gps
tracker; Black wire: connect earth
2.3Features
1. High accuracy. The measurement resolution of oil level is 0.1mm, and it will automatically adjust
temperature from -40 ℃ and 85 ℃ to ensure stable performance in both high and low temperature
environment.
2. High stability. Ultrasonic non-contact measurement avoids sensor corrosion, which is a shortcoming
for normal float, pressure type sensor.
3. Easy installation. Ultrasonic sensor is installed below tank, no need to change or drill, and avoid fuel
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leaking.
4. Strong reliability. moisture proof, acid proofing, antiriot, anti-flaming, quake-proof
3. Installation
3.1Components
1 Signal control box
1 Ultrasonic sensor
1 Power line
1 Sensor signal extension line
1 User interface line
3.2Extra Tools needed
Glue, ribbon, fine abrasive paper (500, 1000, 2000 size each one), rag, a bucket of water, ultrasound
couplant, multimeter, screwdriver
3.3Diagram
Ultrasonic Sensor
Tank Bottom Sensor Effective surface
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A 12PIN Port and Wire Connection Explanation
Number Color Function Remarks
1 Red Positive 9-36V
2 Black Negative
3 NC NC Reserved
4 NC NC Reserved
5 Yellow TXD RS232 Transmitting Terminal
6 Blue RXD RS232 Receiving Terminal
7 NC NC Reserved
8 NC NC Reserved
9 NC NC Reserved
10 NC NC Reserved
11 Green AOUT Analog Output
12 Black GND
B LED Definition
LED Remarks
LED1 Green ON: OK
Red ON: Mal-function
LED2 Green-Power Supply
ON: OK OFF: Fault
Red-AOUT
ON: Fault OFF: OK
C Sensor Usage Explanation
Through extension wire, ultrasonic sensor is connected to sensor port.
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3.4 Digital Display Explanation
A Fault-free status
Fuel level height integral part, unit is CM. E.G. 24CM
Fuel level height decimal part, unit is CM E.G. 0.22CM
Signal strength E.G.3
B Malfunction status
Code Problem
1 Sensor is not connected
2 Sensor falls off
3 Power supply fault
4 Abnormal system reset
5 Analog Output does not match actual level height
6 Current level height is out of range, either too low or too high
In the picture, sensor is not connected and power supply fault.
3.5 Installation Explanation
1. Connect ultrasonic sensor, control box and power lines.
2. Vehicle should park at a flat road and make sure tank bottom is parallel to the road. Fuel amount in
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tank must be no less than 25%.
3. Find a flat area at tank bottom center and make sure it is clean and smooth that no paint or sand. For
the steel fuel tank, sensor installation palce paint should be removed by the sand paper ( Ensure the
smooth surface after rubbing by the sand paper). No other thing should come between sensor and
tank surface.
4. Paste ultrasound couplant to ultrasonic sensor effective surface and attach the sensor to the selected
area closely. NO bubbles. Power ON signal control box and check digital display if displayed value
approximately matches actual fuel level height, and if the signal strength stabilizes between 2-7
without bouncing. If signal strength bounces or above 7, please start fresh from step 3.
5. Clear ultrasound couplant from sensor effective surface and tank bottom, paste glue on sensor and
press it to tank bottom closely. Make sure no bubbles. Keep checking digital display to decide
whether fuel level height or signal strength is abnormal or not. If all is well, keep pressing 6 to 10
minutes till glue is solidified. If fuel level height or signal strength is abnormal, remove sensor from
bottom quickly and start again.
6. Control box is installed at driver’s cab without interfering driving. Sensor power line should connect to
the fuel of car battery. For analog output or RS232 wire connection, please refer to above diagram.
7. Please restart device after installation by cutting electricity.
3.6 Attentions
1. Signal extension line should be properly protected like heat shrink tubing and bundled every 50cm
2. Extension line total must not surpass 15M
3. Power red line is connected to battery positive, black line is connected to car body.
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