1. Introduction
The CERTEON Hall Effect Water Flow Sensor is designed for precise measurement of liquid flow rates. Utilizing the Hall effect principle, these sensors provide a pulse output proportional to the flow, making them suitable for various applications requiring accurate flow monitoring and control. This manual provides essential information for the safe and effective installation, operation, and maintenance of your flow sensor.
Figure 1: CERTEON Hall Effect Flow Meter (YF-S402B model shown)
2. Safety Information and Precautions
Please read and understand the following safety guidelines before installing or operating the sensor:
- To prevent particles or debris from entering the sensor and affecting its performance, a filter screen must be installed at the water inlet.
- The flow sensor is designed for indoor use or installation within equipment. Avoid exposing it to outdoor environments, high humidity, extreme temperatures, or other harsh conditions.
- Keep the sensor away from strong impacts and corrosive chemicals. Do not drop the sensor or subject it to collisions, as this can cause damage.
- Ensure proper electrical connections as described in the installation section to prevent electrical hazards or damage to the sensor.
3. Product Specifications
The CERTEON Hall Effect Water Flow Sensors are available in several models, each with specific characteristics. Refer to the tables below for detailed specifications.
General Model Overview
| Model | Inner Diameter | Flow Range | Thread/Connector Size |
|---|---|---|---|
| YF-S401 (2.0) | 2.0 mm | 0.5–3 L/min | 7 mm thread |
| YF-S401 (3.5) | 3.5 mm | 0.5–5 L/min | 7 mm thread |
| YF-S402 | 7.6 mm | 0.5–6 L/min | M11 × 1.25 thread |
| YF-S402B | 6.5 mm | 0.3–6 L/min | 1/4" PE quick connector |
| YF-S402C | 9.0 mm | 0.5–10 L/min | G3/8 thread |
| YF-S403 | 13.0 mm | 1–30 L/min | G3/4 thread |
Figure 2: Summary of Flow Sensor Models and Basic Characteristics
Detailed Specifications by Model
The following tables provide detailed electrical and performance specifications for individual models.
YF-S401 (2.0) & YF-S401 (3.5)
| Parameter | YF-S401 (2.0) | YF-S401 (3.5) |
|---|---|---|
| Model | YF-S401 (2.0) | YF-S401 (3.5) |
| Thread Size | 7 mm | 7 mm |
| Voltage Range | DC 3.5–24V | DC 3.5–24V |
| Inlet ID / OD | ID: 2.0 mm / OD: 7.2 mm | ID: 3.5 mm / OD: 7.2 mm |
| Thread Length | 14 mm | 14 mm |
| Body Material | POM (Polyoxymethylene) | POM (Polyoxymethylene) |
| Flow Range | 0.5–3 L/min | 0.5–5 L/min |
| Pulse Output Formula | f = 90 × Q (±2%) | f = 43 × Q (±2%) |
| Pulses per Liter | ≈ 5400 pulses/L | ≈ 2580 pulses/L |
| Pressure Resistance | ≤0.8 MPa | ≤0.8 MPa |
| Output High Level | > DC4.7V (at DC5V input) | > DC4.7V (at DC5V input) |
| Output Low Level | < DC0.5V (at DC5V input) | < DC0.5V (at DC5V input) |
| Insulation Resistance | >100MΩ | >100MΩ |
| Pulse Duty Cycle | 50% ±10% | 50% ±10% |
Figure 3: Detailed Specifications for YF-S401 Models
YF-S402 (with Nut)
| Parameter | Specification |
|---|---|
| Model | YF-S402 (With Nut) |
| Interface Size | M11.25 (2分PE) |
| Voltage Range | DC3.5 ~ 24V |
| Inner Diameter | 7.6mm |
| Outer Diameter | 11mm |
| Thread Length | 10.3mm |
| Material | POM |
| Flow Range | 0.5 ~ 6L/min ±3% |
| Pulse Frequency | F=(68Q-2)±2% Q=L/MIN, 4078 pulses per liter of water |
| Water Pressure Resistance | ≤0.8MPa |
| Output Pulse High Level | >DC 4.7V (Input Voltage DC5V) |
| Output Pulse Low Level | <DC0.5V (Input Voltage DC5V) |
| Insulation Resistance | >100MΩ |
| Output Pulse Duty Cycle | 50±10% |
Figure 4: Detailed Specifications for YF-S402 Model
YF-S402B
| Parameter | Specification |
|---|---|
| Model | YF-S402B |
| Interface Size | Quick Connector |
| Voltage Range | DC3.5 ~ 24V |
| Inner Diameter | 6.5mm |
| Material | POM |
| Flow Range | 0.3 ~ 6L/min |
| Pulse Frequency | (Hz)=[38Q]±3% (Q is Flow Rate L/min), 2280 pulses per liter of water |
| Pressure Resistance | ≤0.8MPa |
| Output Pulse High Level | >DC 4.7V (Input Voltage DC5V) |
| Output Pulse Low Level | <DC0.5V (Input Voltage DC5V) |
| Insulation Resistance | >100MΩ |
| Output Pulse Duty Cycle | 50±10% |
Figure 5: Detailed Specifications for YF-S402B Model
YF-S402C
| Parameter | Specification |
|---|---|
| Model | YF-S402C |
| Interface Size | 3/8" (G3/8) |
| Operating Voltage Range | DC3.5 ~ 24V |
| Inner Diameter | 9mm |
| Outer Diameter | 16mm |
| Thread Length | 11.5mm |
| Material | POM |
| Water Pressure Resistance | ≤0.8MPa |
| Output Pulse High Level | >DC 4.5V (Input Voltage DC5V) |
| Output Pulse Low Level | <DC 0.5V (Input Voltage DC5V) |
| Insulation Resistance | >100MΩ |
| Flow Range | 0.5 ~ 10L/min ±3% |
| Flow Pulse Characteristics | (Hz)=[23Q]±3%, 1380 pulses per liter of water |
Figure 6: Detailed Specifications for YF-S402C Model
4. Installation and Setup
Proper installation is crucial for the accurate and reliable operation of your flow sensor.
Physical Installation
- Install the sensor in a horizontal position with the flow direction matching the arrow indicated on the sensor body.
- Ensure a filter screen is installed at the water inlet to prevent debris from entering the sensor.
- Mount the sensor securely to prevent vibrations or movement during operation.
- Refer to the dimensional drawings for appropriate space requirements and connection types for your specific model.
Dimensional Drawings
Figure 7: YF-S401 Dimensional Drawing
Figure 8: YF-S402 Dimensional Drawing
Figure 9: YF-S402B Dimensional Drawing
Figure 10: YF-S402C Dimensional Drawing
Figure 11: YF-S403 Dimensional Drawing
Electrical Wiring
The sensor typically comes with a 3-wire connection. Follow the wiring instructions carefully:
- Red wire (IN): Connect to the Positive Pole of your DC power supply.
- Black wire (GND): Connect to the Negative Pole (Ground) of your DC power supply.
- Yellow wire (OUT): This is the Signal Output Wire, which provides the pulse signal to your control system.
Figure 12: Wiring Method Diagram
5. Operation
The Hall Effect Water Flow Sensor operates by generating a series of electrical pulses. The frequency of these pulses is directly proportional to the rate of liquid flow through the sensor. Your control system (e.g., microcontroller, PLC) will read these pulses to calculate the flow rate.
Pulse Output Characteristics
The relationship between flow rate (Q in L/min) and pulse frequency (f in Hz) is defined by a specific formula for each model, as detailed in the specifications section. For example, for YF-S401 (2.0), the formula is f = 90 × Q (±2%).
Output Waveform
The sensor outputs a square wave signal. An example of this waveform is shown below:
Figure 13: Output Waveform Diagram
6. Maintenance
These Hall Effect Water Flow Sensors are designed for long-term, reliable operation with minimal maintenance. However, adhering to the following guidelines can help ensure optimal performance and extend the product's lifespan:
- Filter Inspection: Regularly check the filter screen installed at the water inlet for any accumulated debris. Clean or replace the filter as necessary to maintain unrestricted flow and prevent sensor clogging.
- Environmental Conditions: Ensure the sensor remains in a stable indoor environment, protected from excessive humidity, high temperatures, and direct exposure to sunlight or harsh weather.
- Avoid Physical Stress: Do not subject the sensor to strong impacts, drops, or collisions. The sealed housing is designed to prevent leakage and ensure durability, but extreme physical stress can compromise its integrity.
- Chemical Exposure: Avoid exposing the sensor to corrosive chemicals, which can degrade the POM body material and internal components.
- Temperature of Liquid: While the sensor is robust, prolonged use with hot water may reduce its overall lifespan. It is recommended for cold or room-temperature water applications.
7. Troubleshooting
If you encounter issues with your flow sensor, consider the following common problems and solutions:
- No Pulse Output:
- Check power supply connections (Red to positive, Black to ground). Ensure the voltage is within the specified DC 3.5-24V range.
- Verify the wiring of the yellow signal output wire to your control system.
- Inspect for blockages in the water inlet or within the sensor. A clogged filter or internal debris can prevent the turbine from rotating.
- Inaccurate Readings:
- Ensure the sensor is installed correctly, with the flow direction matching the arrow on the body.
- Check for air bubbles in the water line, which can interfere with accurate flow measurement.
- Confirm that the pulse output formula used in your control system matches the specific model of your sensor.
- Verify that the water temperature is within acceptable limits, as extreme temperatures can affect accuracy.
- Reduced Lifespan:
- Exposure to hot water over extended periods can reduce the sensor's lifespan. Use with cold or room-temperature water is recommended.
- Repeated physical impacts or exposure to corrosive substances can cause premature failure.
8. User Tips
- For optimal longevity, use the sensor with cold or room-temperature water. Hot water may accelerate wear and reduce the product's operational life.
- Always install a filter at the water inlet to prevent small particles from entering and potentially damaging the internal turbine or affecting measurement accuracy.
- When integrating with a microcontroller, ensure your code correctly implements the pulse output formula (e.g., f = 90 * Q for YF-S401 (2.0)) for precise flow rate calculations.
9. Applications
The CERTEON Hall Effect Water Flow Sensors are versatile and ideal for various applications requiring accurate liquid flow measurement and control. Common uses include:
- Coffee machines
- Water dispensers
- Vending water machines
- Water purification systems
- General flow monitoring and control in small appliances and automated systems.
10. Frequently Asked Questions (FAQs)
- Q1: Can it be used with hot water?
- A1: It is recommended for cold or room-temperature water. Hot water may reduce the product’s lifespan.
- Q2: How accurate is the flow measurement?
- A2: The sensor offers ±2% accuracy, ensuring dependable performance in most applications.
- Q3: Are there any specific precautions during installation?
- A3: Yes, avoid impact, chemical exposure, dropping, or physical collision to prevent sensor damage. Also, ensure a filter is installed at the water inlet.
11. Support and Contact Information
For technical assistance, bulk orders, or any inquiries, please contact CERTEON using the information below:
- Company: SHANGHAI CHIKONG AUTOMATION INSTRUMENT CO., LTD
- WhatsApp: +86 19542723588
- Email: celiachen008@gmail.com
Figure 14: CERTEON Contact Information