W1209 Digital DC12V Temperature Controller Module

The W1209 is a low-cost, easy-to-use digital thermostat module designed for temperature control applications. It features an NTC temperature sensor, relay output, digital display, and control buttons, allowing it to automatically switch devices on or off based on the temperature. 

⚙️ Technical Specifications:

• Power Supply: 12V DC
• Temperature Range: -50°C to +110°C
• Accuracy: ±0.1°C
• Sensor Type: NTC 10K 3950 waterproof probe
• Relay Output: 1-channel relay, supports up to 250V AC / 10A or 14V DC / 10A
• Display: 3-digit 7-segment LED display (shows temperature in °C)
• Adjustable Parameters:
  • P0: Working mode (Heating / Cooling)
  • P1: Hysteresis setting (temperature difference)
  • P2: Maximum temperature limit
  • P3: Minimum temperature limit
  • P4: Temperature calibration
  • P5: Relay delay time
  • P6: High-temperature alarm 

🧰 Typical Applications:

• Incubators
• Aquariums
• Temperature-controlled fans
• Pet heaters
• Greenhouse heating/cooling systems
• DIY refrigerators or heaters 
•  

🔌 Wiring:

• VCC (+12V) → Power supply input
• GND → Ground
• Relay Output Terminal (3 pins): COM (Common), NO (Normally Open), NC (Normally Closed)

Usually, COM and NO are used. When the set temperature condition is met, the relay switches between them.

⚠️ Precautions:

• If controlling high-power devices, consider adding protection (fuse, contactor, etc.).
• Works only with 12V DC. Using other voltages may damage the module.
• Do not exceed the relay’s rated current/voltage.