The YF-S201 Water Flow Sensor is a reliable and widely used flow measurement device designed to monitor the rate and volume of water flow in pipes. It operates using a Hall effect sensor and internal rotor, generating pulse signals proportional to the flow rate.

With a flow range of 1–30 liters per minute and support for up to 1.75MPa pressure, this sensor is ideal for water management systems, automation projects, and IoT applications. Its 0.5-inch (½”) threaded connection allows easy inline installation in standard piping systems.

Features

• Flow measurement range: 1–30 L/min
• Hall effect sensing technology for accurate detection
• Generates pulse output proportional to flow rate
• Compact and lightweight design
• Low power consumption (~15mA)
• High-quality sealing to prevent leakage
• Standard 0.5-inch (½”) pipe connection
• Easy integration with Arduino, ESP32, and microcontrollers
• Durable plastic body with internal rotor mechanism

Specifications

• Model: YF-S201
• Sensor Type: Hall Effect Water Flow Sensor
• Operating Voltage: 5V – 18V DC
• Current Consumption: ≤15mA
• Flow Range: 1 – 30 L/min
• Accuracy: ±10%
• Max Water Pressure: ≤1.75MPa
• Output Type: Digital pulse (5V TTL)
• Pulse Rate: F (Hz) = 7.5 × Flow rate (L/min)
• Pulses per Liter: ~450
• Working Temperature: -25°C to +80°C
• Connection Size: ½ inch (0.5”) threaded
• Wire Interface:
  • Red: VCC
  • Black: GND
  • Yellow: Signal Output

Applications

• Water flow monitoring systems
• Smart water meters
• Liquid dispensing machines
• Irrigation and agriculture systems
• Coffee machines and water dispensers
• Industrial fluid control systems
• IoT-based water usage tracking
• Arduino / ESP32 automation projects

Usage Notes

• Install in the correct flow direction (arrow marked on body)
• Use a filter to prevent debris from damaging the rotor
• Not suitable for high-temperature or corrosive liquids
• For 3.3V microcontrollers (ESP32), use level shifting if required