Themostat XH-W1209

Here is a complete breakdown of the module, how to wire it, and how to program it.

 

Key Features

• Precise Control: Senses and controls temperature with a 0.1°C accuracy.
• Wide Temperature Range: Can be set to control temperatures from -50°C to +110°C.
• Onboard Relay: A built-in 10A-20A relay acts as a switch to control your heater or cooling device.
• Digital Display: The 3-digit red LED display shows the current temperature and programming settings.
• Included Sensor: Comes with an NTC 10K (0.5%) waterproof temperature sensor.

 

Technical Specifications

Feature	Specification
Model	XH-W1209
Operating Voltage	DC 12V
Temperature Range	-50°C to +110°C
Resolution	0.1°C (from -9.9°C to 99.9°C)
Control Accuracy	0.1°C
Refresh Rate	0.5 Seconds
Sensor Input	NTC (10K 0.5%) Waterproof Sensor
Output	1-Channel Relay (10A/20A)
Dimensions	48mm x 40mm

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How to Wire the XH-W1209

This is the most important part. There are two separate circuits to wire:

1. Powering the Module (12V DC): This gives the thermostat’s brain and display power.
2. Powering the Load (Your Device): This is the heater or fan you want to control. The relay (K0/K1) acts as a simple light switch for this circuit.

Connections:

• Sensor:
  • Plug the 2-pin white connector from the NTC sensor into the white socket on the board.
• Module Power (12V DC):
  • +12V: Connect the positive wire from your 12V DC power supply.
  • GND: Connect the negative (ground) wire from your 12V DC power supply.
• Load (Heater/Fan) Terminals (K0 / K1):
  • These terminals are just a switch; they are NOT a power source.
  • Think of the relay as cutting one wire of your device’s power cord.
  • K0: Connect this to the live wire of your device (e.g., your 220V AC live wire or 12V DC positive wire).
  • K1: Connect this to the live wire from your device’s power source (e.g., the wall socket or the 12V supply).
  • The neutral/ground wires of your device are connected as they normally would be, bypassing the thermostat completely.

 

How to Program the XH-W1209

There are two main settings: the Target Temperature and the Programming Menu (P0-P6).

 

1. Setting Your Target Temperature

This is the temperature you want to maintain.

1. Press the SET button once. The display will flash.
2. Use the + and - buttons to choose your target temperature.
3. Press SET again (or wait 5 seconds) to save it.

 

2. The Programming Menu (P0 – P6)

To get the module to behave correctly (i.e., heat or cool), you must set these options.

To Enter the Menu: Press and hold SET for 5 seconds. The display will show P0.

Use + or – to move between P0, P1, P2, etc.

To edit a setting, press SET, use +/- to change the value, and press SET again to confirm.

Code	Name	Description	Range	Default
P0	Heating/Cooling	H = Heating Mode. The relay turns ON when temp is below your target. C = Cooling Mode. The relay turns ON when temp is above your target.	H / C	C
P1	Hysteresis	The “return difference.” How many degrees past the target before the relay turns OFF. This stops the relay from rapidly switching on/off.	0.1 – 15°	2.0°
P2	Upper Limit	The highest target temperature you can set. A safety feature.	110°C	110°C
P3	Lower Limit	The lowest target temperature you can set. A safety feature.	-50°C	-50°C
P4	Calibration	If your sensor is off, you can correct the reading here (e.g., set to -0.5 if it reads 0.5° high).	-7.0 – 7.0°	0
P5	Delay Start	Delays the relay from turning on for a set number of minutes. Useful for compressors.	0 – 10 min	0
P6	High-Temp Alarm	If the temperature reaches this value, the relay will turn OFF and the display will flash ---.	0 – 110°C	OFF

 

Example: Setup for a Chicken Incubator

• Goal: Keep the temperature at 37.5°C using a heating bulb.
• Settings:
  1. Set Target Temp: Press SET, use +/- to set the display to 37.5. Press SET again.
  2. Set Mode (P0): Hold SET for 5s. P0 will show. Press SET. Use + to change it to H (Heating). Press SET.
  3. Set Hysteresis (P1): Use + to go to P1. Press SET. Use +/- to set it to 0.5. Press SET.
• Result: The heater will turn ON when the temperature drops to 37.0°C. It will turn OFF when the temperature reaches 37.5°C.