W1209 Temperature Controlled Thermostat

Temperature Controlled Digital Thermostat W1209

Temperature Control Board Heater Cooler Incubator Aquarium Refrigerator Freezer Oven Boiler

     W1209 is a digital thermostat board powered from 12V DC, with a 3-digit LED display and a relay output. With the waterproof metal-tip NTC 10K temperature probe included in the package it measures air or liquid temperature between -50°C and 110°C, displays it in 0.1°C steps and switches the on-board relay on and off according to the temperature you set. All settings are made with the SET, + and - buttons on the board; no computer or programming is needed.

     It works in heating (H) or cooling (C) mode. In heating mode the relay turns the heater on when the temperature falls to the set point and off when it reaches set point + P1; in cooling mode the relay runs the fan or cooler when the temperature rises above the set point. Hysteresis (P1), temperature correction (P4), delayed start (P5) and high temperature alarm (P6) settings adapt it to the application.

     The 48mm x 40mm board is mounted with screws through the holes at its four corners. Supply (12V, GND) and relay contact (K0, K1) go to the screw terminals, the probe plugs into the white 2-pin socket. It is used for incubators, aquarium water cooling fans, greenhouse heaters, refrigerators and freezers, water tanks and boiler temperature control.

Key features:

     Heating and cooling mode: H (heating) or C (cooling) is selected in menu P0. The same board controls the heater of an incubator or the fan and cooler of an aquarium or cabinet.

     Wide range and 0.1°C display: Measures from -50°C to 110°C; displays in 0.1°C steps between -9.9°C and 99.9°C. The set temperature is also entered in 0.1°C steps.

     Adjustable hysteresis: With P1 the difference between relay on and off is set from 0.1°C to 15°C. A small value keeps the temperature more stable, a large value switches the relay less often.

     Waterproof probe included: The metal-tip NTC 10K probe with about 50cm cable comes in the package and plugs into the white socket; it can be placed in water, soil or inside an incubator.

     Probe correction and alarm: P4 corrects the measured value between -7°C and 7°C; P6 sets a high temperature limit, above which the relay turns off and the display shows "---".

Features:

• Product type: Digital thermostat (temperature control board) with relay output
• Model: W1209
• Supply voltage: 12V DC
• Measuring and control range: -50°C ~ 110°C
• Display step: 0.1°C (between -9.9°C and 99.9°C), 1°C outside this range
• Operating mode: Heating (H) or cooling (C), on-off control
• Hysteresis (P1): 0.1°C ~ 15°C, factory setting 2.0°C
• Temperature correction (P4): -7°C ~ 7°C
• Delayed start (P5): 0 ~ 10 minutes
• High temperature alarm (P6): 0°C ~ 110°C, factory setting off (OFF)
• Output: 1 channel relay, K0 and K1 terminals (dry contact); relay marked "20A 14VDC, 20A 125VAC"
• Recommended load: max 5A at 220V AC (the 20A marking on the relay is not the limit of the board)
• Sensor: NTC 10K thermistor, waterproof metal tip, 2-pin socket
• Display: 3-digit 7-segment LED display
• Buttons: SET, + and -
• Current consumption: less than 35mA with relay off, less than 65mA with relay on
• Measurement refresh: about 0.5s
• Operating environment: -10°C ~ 60°C, 20% ~ 85% humidity (board)
• Connection: screw terminals (12V, GND, K0, K1)
• Color: Green board
• Probe cable length: about 50cm
• Dimensions: 48mm x 40mm, height about 14mm
• Weight: about 20gr

Usage information:

• Connect the positive of the 12V DC supply to the 12V terminal and the negative to GND. Plug the probe into the white socket. Route the supply of the heater or fan through the relay contact (K0 and K1 terminals); the relay shorts these two terminals to run the load.
• Set temperature: press SET once briefly, enter the desired temperature with + and - and press SET again.
• Menu: hold SET for 5 seconds; move between menus P0 ... P6 with + and -, enter a menu with SET, change the value with + and - and save with SET.
• P0: C cooling, H heating (H for incubators). Factory setting C.
• P1 (hysteresis) example: in heating mode with set point 28°C and P1 2.0 the relay turns off at 30°C and turns on again when the temperature falls to 28°C. A smaller P1 keeps the temperature steadier but the relay switches more often; we recommend 0.5°C.
• P2 (110°C) and P3 (-50°C) are the measuring limits of the device, not your on or off temperature; leave them at factory values.
• P4: if the probe reads 3°C high, enter -3; correct it by comparing with a thermometer you trust. P5 (delayed start, minutes) and P6 (high temperature alarm) are left at factory settings unless needed.
• Factory reset: with the supply off, hold the + and - buttons and apply power.
• If the display shows 888 or LLL the probe is not connected or the probe cable is broken (open circuit); temperature cannot be measured.

Areas of use:

•  Incubator temperature control
•  Aquarium water cooling fan and heater control
•  Greenhouse and seedling cabinet heating
•  Refrigerator and freezer thermostat
•  Water tank and boiler temperature control
•  Drying cabinet and fruit-vegetable dryer
•  Electrical panel and device enclosure cooling fan
•  Animal shelter, terrarium and coop heating
•  Industrial cooler and ventilation fan control

Precautions:

•  The board is powered only from 12V DC; do not connect 220V mains to the supply terminals.
•  The relay is marked "20A 125VAC"; this is not the limit of the board. We recommend not connecting more than 5A at 220V AC. Drive large heaters and compressors through a separate contactor or heavy-duty relay.
•  When working with 220V the board is exposed; place it in an insulating enclosure so that the terminals and the underside cannot be touched, and wire it with power off.
•  Only the probe tip is waterproof; protect the board from moisture and water.
•  The 110°C and -50°C values in menus P2 and P3 are measuring limits; do not change them thinking they are the switch-off temperature.

Package contents:

•  1 pcs W1209 Thermostat Module
•  1 pcs Waterproof NTC Temperature Probe (about 50cm cable)
•  Note: 12V adapter and enclosure are not included in the package.