LM YN DC 5V Digital Thermostat Module User Manual

1. Product Overview

The LM YN DC 5V Digital Thermostat Module is a high-precision temperature control device designed for various heating and cooling applications. It features a dual LED display (Red and Green) for clear temperature indication and precise control. This module is equipped with a 20A relay and a 1-meter waterproof NTC sensor probe, making it suitable for a wide range of uses.

Key Features:

• Dual LED display for current and set temperatures.
• Wide temperature range: -58℉ to +257℉ (-50℃ to +125℃).
• High resolution: 0.1℉ for -3.9℉ ~ 99.9℉, 1℉ for other ranges.
• Accurate temperature measurement: ±1℉.
• Fast refresh rate: approximately 0.5 seconds.
• Input Power: DC 5V.
• Relay Load: DC 14V 20A / AC 125V 20A (recommended not to exceed 10A for prolonged use).
• Includes a 1-meter NTC (10K 0.5%) waterproof metal sensor.

Image 1: LM YN DC 5V Digital Thermostat Module with its waterproof sensor probe.

2. Safety Information

Before operating this device, please read all instructions carefully. Improper use can lead to electric shock, fire, or damage to the product. Ensure all connections are secure and correct according to the wiring diagrams. For detailed safety guidelines, refer to the manufacturer's safety document available at: LM YN Digital Thermostat Temperature Controller Module User Manual Download Link.

3. Setup and Wiring

Proper circuit connection is crucial for the safe and correct operation of the thermostat module. Refer to the following wiring diagrams to connect the power supply and your heating/cooling load.

3.1. Circuit Connection Overview

The module requires a DC 5V power input. The relay output can control either AC or DC loads up to 20A (10A recommended for continuous operation). Ensure the temperature sensor is securely connected before powering on the device.

Image 2: Wiring diagrams for controlling AC/DC heating/cooling devices and using a single power supply for both module and load.

Wiring Diagram Descriptions:

• 1. Control AC Heating/Cooling Device: Connect the DC 5V power supply to the module. The AC heating/cooling device is connected to the relay output (K0, K1) and an AC power supply.
• 2. Control DC Heating/Cooling Device: Connect the DC 5V power supply to the module. The DC heating/cooling device is connected to the relay output (K0, K1) and a DC power supply.
• 3. Use One Power Supply to Power the Device and Module at Same Time: For a 12V fan example, the DC 5V power supply powers the module, and the 12V fan is connected to the relay output, drawing power from a separate 12V DC supply. If using a single AC 110V power supply, an AC to DC 12V transformer is needed to power both the module and the 12V fan.

Note: The provided wiring diagrams serve as a reference. Professional installation or consultation is recommended for complex setups.

4. Operating Instructions

This section details how to operate your digital thermostat module, including button functions and parameter settings.

Image 3: Instructions for Use, Part 1, covering basic connections, indicator status, and button functions.

4.1. Indicator and Digital Display Status

• Indicator Light: The indicator light turns off when the relay is disconnected. The indicator light turns on when the relay is pulled in (active).
• Digital Display "--- ": This display indicates one of the following conditions:
  1. The temperature sensor is missing or damaged.
  2. Heating mode high temperature protection is active.
  3. Cooling mode low temperature protection is active.
  In protection mode, the relay is automatically disconnected.

4.2. Use of Keys

The thermostat panel has three buttons:

• "+" Button: Increases the value.
• "-" Button: Reduces the value.
• "SET" Button: Used to access and confirm settings.

4.3. Setting Temperature (Short Press SET)

To quickly set the desired temperature:

1. Short press the "SET" button. The digital display B (green) will flash, indicating it's ready for temperature adjustment.
2. Use the "+" and "-" buttons to adjust the temperature to your desired value.
3. Press "SET" again to confirm the setting, or wait for 5 seconds for the setting to automatically save. The dual LED displays will then show the measured temperature.

Image 4: Instructions for Use, Part 2, detailing short press and long press SET functions for parameter configuration.

4.4. Parameter Settings (Long Press SET)

To enter the parameter setting interface:

1. Long press the "SET" button for approximately 3 seconds. The display will show "P0".
2. Use the "+" and "-" buttons to navigate through parameters P0 to P5.
3. Short press "SET" to select a parameter (e.g., P0). The current setting for that parameter will flash.
4. Use the "+" and "-" buttons to modify the parameter value.
5. Short press "SET" again to confirm the new value and return to the parameter list.
6. To exit the parameter setting interface, long press "SET" again, or wait for 10 seconds for it to automatically exit.

Notes on Parameters:

• P3 (Set Run Time): If set to "1", the thermostat will run for 1 minute and then stop. To trigger it again, long press SET.
• P4 (Set Stop Time): If set to "1", the thermostat will start working 1 minute after the normal work cycle. Press SET repeatedly to trigger again.
• P5 (Data Lock): Default setting is OFF. To prevent unauthorized changes, you can set P5 to ON. Once ON, you need to set P5 to OFF again to unlock and change other settings.

5. Maintenance

To ensure the longevity and accurate performance of your thermostat module, follow these maintenance guidelines:

• Cleaning: Gently wipe the module and display with a dry, soft cloth. Avoid using abrasive cleaners or solvents, which can damage the plastic and electronic components.
• Sensor Care: The NTC sensor probe is waterproof, but avoid unnecessary bending or harsh pulling of the cable. Ensure the sensor tip is clean and free from debris for accurate readings.
• Environmental Conditions: Operate the module within its specified humidity range (20% to 75%). Avoid exposure to extreme temperatures, direct sunlight, or corrosive environments.
• Connection Checks: Periodically inspect all wiring connections to ensure they are secure and free from corrosion or damage.

6. Troubleshooting

If you encounter issues with your thermostat module, refer to the following common problems and solutions:

• Display shows "--- ":
  • Check if the temperature sensor is properly connected. Reconnect it firmly.
  • Inspect the sensor cable for any damage. Replace if necessary.
  • This display can also indicate that the module has entered a protection mode (high temperature in heating, low temperature in cooling). Check your set temperature and current ambient temperature.
• Relay not activating/deactivating:
  • Verify the power supply to the module is DC 5V and stable.
  • Check the wiring to the load (heating/cooling device) according to the diagrams in Section 3.
  • Ensure the set temperature and hysteresis (P1) are configured correctly for your desired operation.
  • Check if P3 or P4 (delay settings) are active and causing a delay in operation.
  • If the indicator light is off, the relay is disconnected. If it's on, the relay is active.
• Temperature readings are inaccurate:
  • Ensure the sensor probe is placed in the area where temperature needs to be measured accurately and is not affected by external heat sources or drafts.
  • Check parameter P2 (Temperature Correction) to ensure no offset has been accidentally applied. Reset to 0 if unsure.
  • Inspect the sensor for physical damage.

7. Specifications

Detailed technical specifications for the LM YN DC 5V Digital Thermostat Module:

• Product Name: High-precision Digital Temperature Control Device
• Model Number: LMYNDT05 (Manufacturer Part Number: DT-40932)
• Input Power: DC 5V
• Display Type: Dual LED (Red + Green)
• Temperature Range: -58℉ to +257℉ (-50℃ to +125℃)
• Resolution: 0.1℉ for -3.9℉ ~ 99.9℉; 1℉ for other ranges
• Temperature Measurement Accuracy: ±1℉
• Hysteresis Accuracy: 0.1℉
• Refresh Rate: Approximately 0.5 seconds
• Measuring Input: 1 meter NTC (10K 0.5%) waterproof metal sensor
• Relay Load: DC 14V 20A / AC 125V 20A (Max. 10A recommended for continuous operation)
• Humidity: 20% to 75% (non-condensing)
• Dimensions (L*W*H): 46 * 40 * 16mm (1.81" * 1.57" * 0.63")
• Weight: 30g (0.06 Pounds)
• Material Type: Metal (sensor probe)
• Control Type: Button Control
• Mounting Type: Wall Mount (via mounting holes)

8. Warranty and Support

8.1. Manufacturer Warranty

This LM YN Digital Thermostat Module comes with a 1-year manufacturer warranty. This warranty covers defects in materials and workmanship under normal use. It does not cover damage caused by misuse, accident, unauthorized modification, or improper installation.

8.2. Customer Support

For technical assistance, troubleshooting beyond this manual, or warranty claims, please contact your retailer or the manufacturer directly. Please have your product model number (LMYNDT05) and purchase information ready when contacting support.