Nozzle with Auto Shut-Off | 11A Dispenser Gun | Petrol Diesel Refueling

This 11a automatic shut off fuel nozzle delivers controlled fluid dispensing up to 60 liters per minute. Built for standard tank filling, the automatic diesel fuel nozzle stops flow immediately once liquid covers the vent port, preventing spills on cars, tractors, and portable storage tanks. Features and Benefits - Venturi shut-off mechanism - Shuts off fuel automatically when liquid touches the spout tip to prevent messy tank overflows - Three-position hold open clip - Lets you set continuous dispensing speeds without holding the trigger down the entire time - Aluminum body with 3/4 inch inlet - Connects directly to standard 3/4 inch fuel transfer nozzle hoses while keeping total weight low - Smooth spout geometry - Fits passenger vehicles and off-road machinery without catching or clicking off early from fuel splashback Applications - Fleet vehicle refueling from transfer tanks or mobile service trucks - Agricultural equipment top-offs including combines, tractors, and stationary generators - Commercial dispensing stations handling diesel, kerosene, and unleaded gasoline Safety & Materials Fuel transfer demands strict safety controls, particularly when handling flammable media like petrol, diesel, and oil. Earthing the fuel nozzle to the delivery tank prevents static discharge from igniting vapours. Standard workshop installations use brass or stainless steel pipe fittings alongside fuel-resistant nitrile seals to eliminate leaks under pressure. How does a fuel nozzle shut off during normal operation? Inside the 11A dispenser gun, a venturi port near the spout tip senses pressure drops. When fuel reaches the spout and blocks this airflow, internal diaphragm vacuum triggers the mechanical lever release, cutting supply instantly to prevent overfilling. Core Parts Needed: To build a monitored dispensing rig using this 3/4 inch inlet nozzle, assemble the following components: - 11A automatic fuel nozzle with 3/4 inch inlet - In-line liquid flow sensor with compatible 3/4 inch threaded ports - Microcontroller board such as an Arduino Uno - 12V to 5V DC step-down voltage converter - Digital display module, either 1602 LCD or OLED - Fuel-rated hose, hose barbs, and stainless steel band clamps - Signal cable with grounded shielding to stop electrical interference - Push button switch for resetting batch volume counts Hardware Connection & Schematic Plumbing begins at the fuel source. Fit the delivery pump, run fuel hose into the in-line flow meter, and terminate at the 3/4 inch inlet of the fuel nozzle. How fuel flow meter works within the line is straightforward: moving liquid spins an internal rotor, allowing a magnetic pickup sensor to generate digital output pulses. For the electrical setup, supply 12V power to the pump and the DC step-down converter. Direct steady 5V power from the converter to the Arduino 5V pin. Connect the flow meter signal wire directly to Arduino digital pin 2, sharing a common ground. Calibration & Math Anyone asking how to make a fuel flow meter reliable must calculate the instrument pulse factor, known as the K-factor. A typical turbine sensor outputs a set frequency per litre per minute. Dispense an exact, known volume of diesel into an approved calibration vessel using the nozzle. Divide total counted digital pulses by the dispensed volume in litres to determine your specific pulses-per-litre figure. In code, measure pulse intervals via interrupts. Multiply frequency by sixty, then divide by your verified K-factor to calculate instantaneous flow rate in litres per minute, updating the running volume total with every single pulse received. Arduino Code Example volatile unsigned long pulseCount = 0; float calibrationFactor = 450.0; float totalLitres = 0.0; void pulseCounter() { pulseCount++; } void setup() { Serial.begin(9600); pinMode(2, INPUTPULLUP); attachInterrupt(digitalPinToInterrupt(2), pulseCounter, FALLING); } void loop() { static unsigned long oldTime = 0; if ((millis() - oldTime) > 1000) { detachInterrupt(digitalPinToInterrupt(2)); float flowRate = ((1000.0 / (millis() - oldTime)) pulseCount) / calibrationFactor; oldTime = millis(); totalLitres += (pulseCount / calibrationFactor); pulseCount = 0; attachInterrupt(digitalPinToInterrupt(2), pulseCounter, FALLING); Serial.print("Litres: "); Serial.println(totalLitres); } }