Capacitive fuel level sensor with accelerometer
- 1. USER GUIDE FUEL LEVEL SENSOR GPSM PRO SENSOR Intelli LLC Ukraine, 03035, Kyiv, Lva Tolstogo street, 63 tel.: +38 (044) 3622956 fax: +38 (044) 2494445 E-mail: info@fuel-sensor.com www.fuel-sensor.com www.intelli.com.ua Revision: 5.03 Enable 3D View
- 2. Contents 1. Fuel level sensor application.........................................................................................................3 2. Specifications ................................................................................................................................3 3. General view .................................................................................................................................5 3.1. Dimensions ............................................................................................................................5 3.2. Description of connector pins ...............................................................................................5 4. Wiring diagram to connect the power supply and control module .............................................6 4.1. Diagram of wiring through the battery disconnect switch ...................................................7 4.2. Diagram of avoiding the battery disconnect switch..............................................................7 5. The GPSM Pro Sensor installation and calibration .......................................................................7 5.1. Installation procedure ...........................................................................................................9 5.2. Tank tare..............................................................................................................................10 6. Operation concept ......................................................................................................................10 7. Operating rules ...........................................................................................................................10 8. Component parts ........................................................................................................................10 9. Servicing......................................................................................................................................11 10. Repair ......................................................................................................................................11 11. Warranty .................................................................................................................................11 Attachment А. The unit calibration guide
- 3. 1. Fuel level sensor application GPSM Pro Sensor is applied for measuring the level of fuel and lubrication materials (like diesel oil, petrol, paraffin oil) and other dielectric liquids keeping its physical character at the operating temperature range. The given manual describes the operation and setting of GPSM Pro Sensor, hereafter referred to as “sensor”, in conjunction with the fuel metering systems. Observe job safety rules before installation of the fuel level sensor! 2. Specifications Electrical specification DC supply voltage, V 9 - 30 Input current (at 12V), mA max 50 Serial interface RS-485, RS-232 (optionally) ADC bit capacity 12 Level gauging Bit rate, Mbit/s 1200, 2400, 4800, 9600, 19200, 38400, 57600, 115200 Averaging time, s 0 - 100 Automatic data output interval, s 0 - 255 Measuring period, s 1 e erat re eas r n ran e, С - 80 … + 80 Computer controlled accelerometer calibration yes Liquids to be measured Fuels petrol, diesel oil, paraffin oil Oils Engine oils, transmission lubricants, power steering fluids and hydraulic oils Bio fuel Ethanol Е100, Е85, Е50, Е20, Е10, ethanol Range Accuracy Rate of ambient temperature change -20 С…+80 С, % ax ±0,7 Rate of ambient temperature change -80 …+80 С, % ax ±0,9 Operation conditions IP Code IP 67 erat n te erat re, С -80…+80 EMC Immunity Level SAE J1113/2 1996 Figure 1 shows the straight-line relation between the fuel level and sensing data. Figure 2 provides data about relation between accuracy and temperature. Figure 3 shows volume and temperature relationship of a fuel. For demonstration purposes, this relationship showed for diesel oil with average density.
- 4. Fig. 1. Metrological characteristics of the fuel level sensor. Fig. 2. Constancy of Pro Sensor fuel gauge unit readings at -60 °С… +80 °С temperature range. Fig. 3. Relation between diesel fuel volume and temperature. Average density of the diesel fuel (810kg/m3) at 20 °С. 0 500 1000 1500 2000 2500 3000 3500 4000 4500 0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100% Unitreadings Fuel level Relation between fuel level and output data 0,0% 0,1% 0,2% 0,3% 0,4% 0,5% 0,6% 0,7% -60 -40 -20 0 20 40 60 80 Additionalpercentageerror,% Temperature, °С Relation between accuracy of the fuel level sensing and temperature of the environment 1,149 1,169 1,189 1,209 1,229 1,249 1,269 1,289 -60 -40 -20 0 20 40 60 80 Specificvolume,l/kg Temperature, °С Relation of fuel level and temperature
- 5. 3. General view 3.1. Dimensions 33мм 67мм 25мм L 1 2 3 4 5мм 67мм 330±100мм 5 http://fuel-sensor.com Fig. 4. General view, mounting dimensions of the Pro Sensor. 1 - he eas r n art of the n t has a len th of 200…6000 and cons sts of two arallel aluminum tubes having anodized coating. 2 - The case made of high-strength polymer. 3 - Flexible protection tube. 4 - Four-pin connector. 5 - Fixing holes. Due to the commonly used location of holes, the unit can easily be mounted instead of the regular (float sensors) fuel gauge units. 3.2. Description of connector pins A – + 9-30 V B – B (RS-485) C – GND (-) D – A (RS-485) Fig. 5. The layout of the connector pins of Pro Sensor unit.
- 6. red/green yellow blue black/brown Fig. 6. The layout of the pins of Pro Sensor fuel gauge unit. А – yellow; В – blue; «+» – red/green; GND («-») – blackbrown. The Pro Sensor is protected against polarity reversal; the protection against polarity reversal will protect the electronics from incorrect connection of the voltage. RS-485 circuits are protected from overvoltage (up to 30V) and short circuit. The improper connection of the unit results in termination of the warranty liabilities of the unit supplier. Regardless the unit modification, it is prohibited to connect the unit to the in vehicle network without installing two additional fuses for “+” and “-” that come with the unit. The fuses should have a capacity less than 500 mA. 4. Wiring diagram to connect the power supply and control module There are two recommended schemes to connect the power supply: 1) Connection to the power of the vehicle with the battery disconnect switch. 2) Connection to the power supply avoiding the battery disconnect switch. Pro Sensor has a galvanic isolation (1000 V) between its electric circuits. Besides, the unit polymeric case is isolated from the car body. That is why the Pro Sensor can be connected directly to the car battery avoiding the battery cut off switch.
- 7. 4.1. Diagram of wiring through the battery disconnect switch Vehicle battery Fleet management terminal RS485 A RS485 B Battery disconnect switch GPSM Pro sensor with built-in galvanic isolation F1F2 F3 Vehicle electrical system The unit case has electric isolation from the car disconnect switch Fig. 7. Connection diagram №1. Connecting the unit to the power source through the battery disconnect switch. 4.2. Diagram of avoiding the battery disconnect switch Vehicle battery Fleet management terminal RS485 A RS485 B Battery disconnect switch GPSM Pro sensor with built-in galvanic isolation F1 F2 F3 Vehicle electrical system The unit case has electric isolation from the car disconnect switch Fig. 8. Connection diagram №2. Connecting the unit to the power source directly to the vehicle’s battery. 5. The GPSM Pro Sensor installation and calibration It is recommended to install the fuel level sensor in geometric center of the fuel tank. It helps to reduce error in measurement when the vehicle is inclined. If it is needed to install two sensors
- 8. in one tank, they should be placed in one diagonal line. Examples of the proper sensor mounting are given below: Fig. 9. Tank, side view. Recommended installation place. It is recommended to install two units in a tank to reduce the measurement uncertainty when the vehicle is inclined or if the tank length exceed 1.2 meters. 68% 32% 50% 50% 32% 68% 32%+68% 2 50% 68%+32% 2 50% Fig. 10. Tank, side view. Installation of two sensors in one tank. Place the fuel level sensor as close to the tank geometric center as possible. If two sensors installed into one tank, they should be placed on one diagonal line. GPSM GPSM GPSM Fig. 11. Tank, top view. Recommended positions for installation of one or two Pro Sensor units.
- 9. 5.1. Installation procedure It is required to remove the tank, fill it with water and/or evaporate residual fuel before starting the unit installation! It also refers to all tanks containing flammable liquids. Dealing with diesel fuel tanks, it is required to get rid of the fuel steams to avoid the explosion! 1. Having finished the steaming, drill a small hole on the unit would-be location. Take a rod and check for the absence of blocks like bumps/dimples in a tank bottom or a baffle. 2. Make a hole in a tank (35-40mm) with a crown milling cutter or dual-cut drill. 3. Measure the tank height and cut the unit making it 10-200 mm shorter than a tank. 20 мм L, мм Fig. 12. Choosing the Pro Sensor unit length. 4. Remove the cutting burrs from the unit tubes. 5. Try the unit on a tank and mark the positions for drilling the holes for five self-tapping screws. 6. Drill the holes for self-tapping screws. 7. Perform the unit calibration testing (see Attachment A) 8. Install the unit with a sealing; screw the self-tapping screws supplied as a set tightening every next screw located opposite. Fig.13. The sequence of tightening the self-tapping screws while installing the Pro Sensor fuel gauge unit.
- 10. 9. Enable the unit to the extending cable by connecting the pins, after putting two additional fuses for “+” and “-” of the in vehicle network. 5.2. Tank tare Calibration test means obtaining a table of correspondence of the unit output signal (in nominal units) to the fuel volume. 1. Before starting calibration, put the vehicle on the level ground. 2. Drain the fuel from the tank. 3. Fuel until the unit readings start changing. Write the unit readings and the used fuel volume into a Table. 4. Fill the tank with 10-40 liters of fuel at a blow (depending on the tank volume) and each time write the output signal values and the corresponding amount of fuel into a Table. 6. Operation concept The unit uses the capacity method of measuring the liquid level, which is based on the dependence of capacity of condenser from dielectric capacitance of the medium between its plates. For the operational comfort, Pro Sensor unit has a built-in LED having two operation modes: 1) Flashing at the unit acceleration and tank vibration; 2) Flashing at transferring the data to an external device. You can switch the LED off at the settings of the unit profile program. 7. Operating rules The unit operating rules: - it is prohibited to expose the unit to aggressive influences, magnetic fields having the activity exceeding the one specified in SAE J1113/2 1996, mechanical stresses, sudden alteration of temperatures differing from the natural ones, also to operate the unit under conditions differing from conditions described in this manual; - it is prohibited to connect the unit to devices having interface differing from the one described in this manual; - the installation and setting of the unit should be performed by the staff who has studied the occupation standards, the unit operation concept, its operating features and technical specification. 8. Component parts The supply package includes: - Pro Sensor fuel gauge unit; - extension cable (up to 8 m); - rubber pad;
- 11. - self-tapping screws (5 pcs) fastening the unit to a tank; - a fuse for a fuel gauge unit; - a device for setting the fuel gauge unit (optional); 9. Servicing The unit does not require servicing. 10. Repair The unit is maintainable if there is no mechanical damage. 11. Warranty Warranty period is 24 months since production date. The production date can be seen in the unit datasheet. Removing the device number from the unit leads to the cessation of the warranty. The manufacturer guarantees the normal operation of the unit if the customer follows the operating rules.