ME201WC Ultrasonic Liquid Level Monitor User Manual

1. Introduction

The ME201WC is a digital ultrasonic liquid level monitor designed for remote monitoring of water and oil tanks. It integrates with the Tuya SmartLife app via WiFi, providing real-time data and control over connected pumps. This device is suitable for home automation systems and various plumbing applications, offering reliable liquid level measurement and alarm functions.

2. Safety Information

Please read and understand all safety instructions before installation and operation. Failure to follow these instructions may result in electric shock, fire, or serious injury.

• Ensure the power supply is disconnected before performing any wiring or installation.
• Only use the specified power supply (100-240VAC to DC 5V) for the device.
• Do not expose the device to extreme temperatures outside its operating range (-20°C to 70°C).
• Keep the device away from strong electromagnetic interference.
• Ensure all connections are secure and properly insulated.

3. Product Overview

3.1. Components

• ME201WC Wireless Level Sensor
• AC/DC Adaptor (100-240VAC to DC 5V)
• Solid State Relay (for pump control, if included/connected)
• Water Pump (user-supplied, if connected)

3.2. Features

• Type: Digital
• DIY Supplies: Plumbing
• Brand Name: morayelec
• Model Number: ME201WC
• Origin: Mainland China
• Certification: CE
• Product Name: Fluid Level Monitor
• Application: Water /Oil Tank
• Usage: Home Automation System
• Operating Temperatures: -20°C to 70°C
• Operation System: Android, iOS APP
• APP: Tuya SmartLife
• Measuring Range: 0.1m ~ 4.0m
• Accuracy: ±0.02m
• Power Supply: 100-240VAC to DC 5V
• Relay: 40A@480V AC (if connected)
• Network Mode: 2.4G WiFi (max 50m no obstacle between sensor and router)
• Protection: IP65

3.3. Product Diagrams and Applications

4. Setup

4.1. Physical Installation

1. Remove the release paper from the gasket and attach the gasket to the center of the tank where the hole will be drilled.
2. Drill a hole in the middle of the tank with a diameter of >55mm.
3. Place the sensor over the gasket, ensuring it is aligned with the screw holes and unobstructed.
4. Fasten the sensor with a self-tapping screw.

Note: If the mounting surface is curved, fix the sensor with screws to prevent stress. If data is abnormal, loosen the screws slightly.

Installation Guidelines to Avoid Pseudo-Echo

• Hold the sensor perpendicular to the liquid surface.
• Install the sensor away from the water inlet to avoid pseudo-echo.
• The sensor installation cannot be close to the bulkhead, otherwise it will cause a strong pseudo-echo.
• Ensure no obstacles are present in the reflective area of the sensor.

4.2. Wiring

Refer to the electrical definition and diagram for proper wiring of the sensor and any connected pump/relay.

Note: The diagram in Figure 1 and 2 provides a visual representation of the wiring connections.

4.3. App Connection (Tuya Smart / Smart Life APP)

1. Power on the AC/DC ADAPTOR first, and then power on the sensor. The sensor's LED light will flash.
2. Scan the QR code provided in the product packaging or search your app store to download the "TUYA Smart APP" or "Smart Life APP" on your mobile device.
3. Network Reset: Press and hold the button on the sensor for 5 seconds. The LED light will flash rapidly. Release the button to initiate network reset. The device will then attempt to connect to the network automatically.
4. Connecting Sensors to APP:
   • Turn on WiFi and Bluetooth on your phone.
   • Open the app and navigate to the "Add Device" section.
   • The app should automatically detect nearby devices. Select the ME201W Level Sensor.
   • Follow the on-screen prompts to enter your WiFi information (password) and complete the connection.
   • Once connected, click on the Level Sensor in the app to enter its liquid level interface.

Important Notes:

• WiFi frequency can only be 2.4GHz, not 5GHz.
• When adding a device, ensure that the sensor and your phone are connected to the same WiFi network.
• After successful setting, the indicator must work under steady light. If the phone cannot find the device or fails to connect, hold down the button for 5 seconds until the indicator flashes to add the device again.

5. Operation

5.1. App Interface and Settings

Once connected, the app will display real-time liquid level information:

• Liquid Level Ratio: Percentage of liquid in the tank.
• Liquid Level Depth: Actual depth of the liquid in meters.
• Liquid Level Status: Indicates Normal, Lower Alarm, or Full Alarm.
• Supply Voltage: Current voltage of the sensor.

Initial Settings:

1. Installation Height (A): Set the distance from the sensor to the tank bottom.
2. Liquid Maximum Depth (B): Enter the maximum height of liquid the tank can hold.
3. Set Max: Configure the high-level alarm threshold (actual liquid level value C).
4. Set Min: Configure the low-level alarm threshold.

Example: Installation height A=4m; Liquid maximum depth B=3m; Actual liquid level value C=2m; Set Max=60%, Set Min=20%. Level Status: Full alarm (C/B*100% = 2/3*100% = 67%).

5.2. Auto Pump Control

The level sensor can automatically control a connected pump based on liquid levels.

• On-Auto (Default): The pump is automatically controlled by the full and low alarm values.
• Off-Manual: The full and low alarm values do not control the pump automatically.

5.3. Pump Working Mode

• Supply (Refilling Water) (Default): When a full alarm is triggered, the pump turns off. When a low alarm is triggered, the pump turns on.
• Drainage: When a low alarm is triggered, the pump turns off. When a full alarm is triggered, the pump turns on.

5.4. Pump Switch

This allows for manual control of the pump.

• On-Start: Turns on the pump manually.
• Off-Stop (Default): Turns off the pump manually.

Note: When Auto Pump Control is enabled, the Pump Switch status will update automatically.

5.5. Liquid Level Status Demonstration

Video 1: Demonstration of the ME201WC liquid level sensor showing real-time liquid level changes and alarm notifications (Lower alarm, Full alarm) on the smartphone app.

6. Maintenance

• Regularly inspect the sensor for any dirt, debris, or obstructions that might affect its accuracy. Clean gently with a soft, damp cloth if necessary.
• Ensure all wiring connections remain secure and free from corrosion.
• Periodically check the sensor's mounting to ensure it is still perpendicular and securely fastened, especially if installed on a curved surface.

7. Troubleshooting

7.1. Common Issues

• Device not connecting to WiFi:
  • Ensure your WiFi network is 2.4GHz (5GHz is not supported).
  • Make sure your phone and the sensor are connected to the same WiFi network during setup.
  • Perform a network reset by holding the sensor button for 5 seconds until the LED flashes rapidly, then try connecting again.
  • Ensure the sensor is within 50m of the router without significant obstacles.
• Inaccurate liquid level readings or data abnormal:
  • Check the sensor installation for pseudo-echo issues (refer to Section 4.1 and Figure 6). Ensure it's perpendicular, away from water inlets, and not too close to bulkheads.
  • If installed on a curved surface, ensure the mounting screws are not overtightened, which can stress the sensor. Loosen them slightly if necessary.
  • Verify that the 'Installation Height' and 'Liquid Maximum Depth' settings in the app are correct.
• Pump not activating/deactivating as expected:
  • Check the 'Auto Pump Control' setting in the app. If set to 'Off-Manual', the pump will not operate automatically.
  • Verify the 'Pump Working Mode' (Supply/Drainage) is correctly configured for your application.
  • Ensure the 'Set Max' and 'Set Min' alarm thresholds are appropriately set.
  • Confirm the solid-state relay and pump are correctly wired and functional.

7.2. User Tips

• For pump control, ensure you understand the difference between 'Supply' and 'Drainage' modes to prevent unintended pump operation.
• Always double-check your wiring, especially for the solid-state relay, to ensure the pump operates safely and as intended. The electrical diagram in Section 4.2 is crucial for this.
• If you experience connection issues, try restarting your router, phone, and the sensor before attempting to reconnect.

8. Specifications

9. Warranty and Support

For warranty information, technical support, or further assistance, please contact your retailer or the manufacturer directly. Keep your purchase receipt as proof of purchase.

A detailed user manual in PDF format is also available for download: View User Manual (PDF)