Gravity: Water Flow Sensor 1/2" - Arduino Liquid Flow Meter
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Gravity: Water Flow Sensor 1/2" - Arduino Liquid Flow Meter
The Gravity: Water Flow Sensor (1/2") is a high-quality, compact water flow sensor designed to accurately measure liquid flow rates. Built around the YF-S201 sensor, it includes a plastic valve body, flow rotor, and hall effect sensor that work together to output a pulse signal corresponding to the liquid flow rate. When liquid flows through this G1/2 flow sensor, the magnetic rotor spins, generating pulses that can be read by any microcontroller, such as an Arduino Arduino flow meter system.
This water flow sensor is commonly used at the inlet end of water systems and is ideal for monitoring applications like coffee machines, irrigation systems, home appliances, and automated water control systems. With a Gravity interface, this liquid flow rate sensor is fully compatible with the Arduino IO Expansion Shield, making the Arduino flow meter an easy plug-and-play solution for your projects using a G1/2 flow sensor.
Projects
Key Features
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Measures flow rates from 1–30 L/min
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Compatible with Arduino and other microcontrollers for Arduino flow meter setups
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Gravity interface for easy connection to water flow sensor modules
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Outputs pulse width signal proportional to liquid flow rate
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Durable plastic valve body with magnetic rotor and hall effect sensor
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High accuracy: ±5% (2–30 L/min) for G1/2 flow sensor accuracy
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Ideal for real-time flow monitoring and automation with a water flow sensor

Specifications
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Inner Diameter: 11 mm
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Outer Diameter: 20 mm
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Operating Voltage: 3.5–12V
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Current Consumption: 15 mA (at 5V)
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Flow Range: 1–30 L/min
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Accuracy: ±5% (2–30 L/min)
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Output Signal: Pulse (1L = 450 pulses)
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Pulse High Level: >4.7V
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Pulse Low Level: <0.5V
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Duty Cycle: 50% ± 10%
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Proof Water Pressure: <1.75 MPa
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Operating Temperature: Liquid < 120°C
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Working Humidity: 25%–95% RH (no frost)
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Insulation Resistance: >100 MΩ
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Dimensions: 62 x 36 x 35 mm
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Weight: 52g

Application Notes
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Use this water flow sensor with a 20 mm rifled pipe for optimal performance
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Avoid contact with corrosive liquids
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The G1/2 flow sensor must be installed vertically with no more than 5° tilt
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Ensure the liquid temperature stays below 120°C for consistent liquid flow rate monitoring
In the Box
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1 x Gravity - Water Flow Sensor - 1/2"

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2.1 Germany Domestic Shipping
| Shipping Method | Order Value | Cost | Est. Delivery |
|---|---|---|---|
| Deutsche Post | €0.00 - €50.00 | €4.95 | 2-4 Business Days |
| Deutsche Post | Over €50.00 | Free | 2-4 Business Days |
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DHL Paket (Faster Delivery) |
€0.00 - €50.00 | €6.95 | 1-3 Business Days |
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DHL Paket (Faster Delivery) |
€50.00 - €100.00 | €2.00 | 1-3 Business Days |
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DHL Paket (Faster Delivery) |
Over €100.00 | Free | 1-3 Business Days |
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| Shipping Method | Order Value | Cost | Est. Delivery |
|---|---|---|---|
| FedEx Regional Economy | €0.00 - €100.00 | €7.95 | 3-5 Business Days |
| FedEx Regional Economy | Over €100.00 | Free | 3-5 Business Days |
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| Region | Shipping Method | Order Value | Cost | Est. Delivery |
|---|---|---|---|---|
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Continental U.S. (50 States) |
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| USPS Ground Advantage | Over €45.00 | Free | 3-7 Business Days | |
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| USPS Priority Mail | Over €45.00 | €14.95 | 1-4 Business Days | |
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Non-Continental U.S. (AK, HI, PR, etc.) |
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|---|---|
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