After correct connection(can be viewed in), we move on to setting the temperature and other settings.
Depending on what we need to heat or cool (at a given temperature, the relay will either close or open the contacts), we set one of two modes: cooling or heating. To do this, press and hold the "SET" button for more than two seconds, the display will show "P0", which means that we have entered the program menu. The "+" and "-" buttons navigate through the program menu, but in our case we are at the desired value "P0", so we press the "SET" button again and select the desired mode: "C" is cooling, and "H" heat.
The next setting in the "P1" menu is hysteresis, this is the temperature difference at which the thermostat turns on or off, ( factory setting 2°C). For example, the thermostat is set to turn off at +40°C, when this temperature is reached, the relay will open. And it will turn on only when the temperature drops to the set hysteresis, that is, at + 38 ° C.
The next two menu items are:
- "P2" upper limit for setting the maintained temperature ( factory setting+110°C).
- "P3" lower limit for setting the maintained temperature (factory setting -55°C). When these temperatures are reached, the W1209 thermostat will turn off.
The menu item "P5" is responsible for the delay of the relay on time, it can be set up to 10 minutes. (default setting 0 min).
The last item "P6" allows you to control the overheating protection. OFF – protection is disabled, ON – protection is enabled.
Setting the temperature: press the "SET" button, the indicator will blink, use the "+" and "-" buttons to set the desired temperature.
To reset to factory settings, you must:
- turn off the power
- press and hold the "+" and "-" buttons
- apply power to the thermostat
The LED display will show "888" followed by the current temperature.
From this article you will learn what the W1209 device is, how it works, how to connect it.
Shipped from China in 2-8 weeks. Free delivery. Item will be shipped within 1 business day after payment is received. Included with the product will be only a board, a bag, a microcircuit and a sensor.
The thermostat is small. If you compare it with a matchbox, it will look even smaller.
The most noticeable detail of the product is a digital display that shows the temperature down to one tenth of a degree. There are also three buttons and slots for connecting special wires.
W1209 connects very simply. Even ordinary user, who has no idea about electricity and the principles of its work, will be able to do it on his own and without any effort. To connect an electronic thermometer, you need to find a special socket under the right screw, to the right of the display.
Temperature controller W1209 ideal for temperature control of a homemade incubator. You can buy it for only 145 rubles on the Bangud website by clicking on this link .
Wiring diagram W1209
W1209 works from direct current- 12 volts. Below is a diagram for connecting the W1209. There are four slots on the central unit. The left two slots are for connecting heating elements, the right two are for connecting power.
According to the diagram, the thermostat can be powered from a 220 volt network. However next element in this circuit there must be a special transformer that could convert 220 volts to 12 volts DC.
To the left of the gray block is located heating element(with two characters), which can be connected directly to the W1209. The contact opens in the thermostat and the heater turns off.
Work W1209 on the example of connecting to an incubator
The connection diagram of the thermostat here is almost the same as described above, only the heating elements are added more: a cooling fan, a 12 volt adapter, a fan, a heating element - incandescent bulbs.
The figure below shows the diagram by which the incubator is connected. The wires of all electrical appliances are connected to the W1209 thermostat. Let's start with AC input.
On the right side, you can see the block for connecting the thermostat to a 220-volt DC network. However, it is not connected directly, but through a 12-volt adapter that converts 220 to 12 volts. This adapter is connected to two right slots - "minus" and "plus".
In addition, a 12 volt fan is connected to the same wires. Incandescent lamps are connected to the two left slots. Please note that the light bulbs are connected to the network directly without transformers.
The thermostat itself provides a mode in which, in the event of an increase normal temperature, the circuit opens automatically and the lights go out. The lamps themselves are connected in parallel so that more powerful incandescent bulbs can be screwed in and also they could only work at half their power.
The W1209 temperature sensor is not made in the best way, because the length of its wires does not exceed 50 centimeters. In most cases, this is not enough for the correct installation of the device in order to correctly measure the temperature.
Since the display only shows us the current temperature value, the user will want to set the desired value for him. How to do it? As mentioned above, there are three more buttons on the thermostat: “set”, “plus” and “minus”.
Thanks to these buttons, you can set the desired temperature parameters. This is done as follows - first you need to press the "set" button, then use the "minus" and "plus" buttons to set the required temperature at which the relay will turn on. Actually, the sensor will monitor these indicators.
If the temperature is below the set value, then the contacts of the power terminals will close. The thermostat must be paired with a heater or cooler. If you hold down the "set" button for five or more seconds, then the W1209 will enter the settings mode. The following settings are available:
P0 - choice of heater or cooler
P1 - hysteresis 0.1-15 °C, default 2 °C
P2 - setting the upper operating temperature limit by default 110 ° C
P3 - setting the lower operating temperature limit by default -50 ° C
P4 - temperature correction -7 +7 ° C, default 0
P5 - relay on / off delay 0-10 sec, default 0
P6 - alarm overtemperature 0 +110 °C, off by default
Where P is the program, H is the heater (from the English heat, hot) and C is the cooler (cool). Mode P1 is a hysteresis that keeps the temperature fluctuation within certain limits. It is set in the settings.
Unfortunately, you cannot make all equipment work exclusively from a 12 volt adapter, because this voltage will not be enough to turn on incandescent lamps.
Another option for connecting the thermostat is the ability to connect it not to a constant voltage network (220 volts), but to a 12 volt power source, for example, it can be a car battery.
The figure below shows the connection diagram battery to the thermostat. To the left of the w1209 is a heating element that runs on 12 volts.
Outcome
The W1209 thermostat is an excellent product for temperature control applications such as homemade device like an incubator. It perfectly maintains the optimum temperature.
In case of failure during a sudden power surge, it can be replaced with an analog. In addition, it costs 140-150 rubles. W1209 - very easy to use, even the most novice user without much knowledge of how it works electrical circuit be able to plug it in and use it effectively.
Thermostat W1209 - video on how to use this device
The W1209 digital thermostat module from China is popular because of its versatility and attractive price.
It can be used for both the incubator (in "heating" mode) and for the fan (in "cooling" mode).
It can also be used to control and maintain the temperature of the engine in a car or car interior by connecting an electric fan to its contacts. Suitable for cooling system block computer or, for example, attach to a freezer, water tanks, steamer, industrial equipment, underfloor heating, baseboard or ceiling and many other temperature-controlled heating or cooling systems.
For the module, you can also inexpensively buy a collapsible transparent case. 
It should be noted that you do not need to use an additional thermometer to work with the module — it displays the actual temperature value in the sensor area. The module comes with a waterproof temperature sensor (NTC 10K 0.5%).
W1209 MODULE DIAGRAM
For proper and long-term operation of the thermostat, it is necessary to supply a stabilized power supply of +12 volts. The module remains operational when the power supply drops to 10V. A 5V stabilizer (m / s AMS1117) is installed on its board.
There is a relay on the module board that switches the load with voltage up to 220V, current up to 10A.
Specifications W1209:
- Temperature control range: – 50 … + 110 ° C
- Resolution: 9.9 to 99.9; 0.1°C; 1 ° C
- Measurement accuracy: 0.1 ° C
- Control accuracy: 0.1°C
- Accuracy (Hysteresis): 0.1 to 30°C
- Temperature update rate: 0.5 sec.
- Power supply: + 12 V (stabilized!)
- Measurement inputs: NTC (10K 0.5%)
- Output: relay contacts 14V to 20A, 125V to 20A, 220V to 10A.
Operational requirements:
- Medium temperature: -10 … + 60 ℃
- Humidity 20% ... 85%
- Power consumption:
- Current: 22mA (with relay off)… 72mA (with relay on)
- Size: 48 (L) x 40 (W) x 14 (H) mm
- Total weight: 20g
Temperature setting
Briefly press the “SET” button and then use the “+” and “-” buttons to set the value of the maintained temperature. Press “set” again and the thermostat will save the value and switch to the mode of maintaining the set temperature.
Programming mode
To enter the programming menu, press and hold the "SET" button (about 5 seconds). You will enter the main settings menu. To switch modes P0 … P8, press + or -. To change modes P0 ... P8, press the "SET" button, then + or -. Long press SET (about 5 seconds) or within 10 seconds if no button is pressed, the memorization and exit from the menu will occur.
Setup menu (default values in brackets)
Modules are produced with two firmware versions:
Menu for new firmware
- P1 - hysteresis settings - 0.1 - 30 (2)
- P4 - Temperature error correction -7 ... +7 ° C (0)
- P5 - Start time delay - 0 ... 600 sec (0)
- P6 - Alarm (this function is not used)
- P7 - Upper alarm temperature threshold - 0 ... 110 ° C (OFF) (forced switch-off of the relay, dashes light up on the screen -)
- P8 - Reset to factory settings - S / N (when you switch the parameter, all settings are reset)
Menu for old firmware
- P0 - Cooling / Heating - C / H (C)
- P1 - hysteresis settings - 0.1 - 15 (2)
- P2 - setting the upper limit +110 ° C (110)
- P3 - setting the lower limit - 50 ° C (-50)
- P4 - Temperature error correction -7 ... +7 ℃ (0)
- P5 - Start time delay - 0 ... 10 Minutes (0)
- P6 - Upper alarm temperature threshold - 0 ... 110 ℃ (OFF) (forced switch-off of the relay, dashes light up on the screen -)
Module malfunctions
If on the display: L L L- broken temperature sensor;
N N N or 110 - short circuit of the temperature sensor;
888 - on the display with a new firmware, it means a sensor malfunction (open or short circuit).
Reboot. If the module “freezes”, the display does not light up or the module behaves inappropriately, and the power supply to the module (DC 12 V) is supplied, you need to restart the module and return all settings to the factory values. To do this, turn off the power to the module, press the "+" and "-" buttons simultaneously and then turn on the power to the module.
Modification of the module
On the board, the RESET input (4 pin of the controller) is brought to the contacts for programming and the controller is sometimes falsely reset from strong spark interference from the relay or from the power supply. The upgrade consists in installing a 0.1 uF capacitor on the common wire (-).
Flashing the W1209 module
Sometimes a module starts acting strange, buggy, etc. To flash the module, we need:
- USB programmer ST-Link V2. The cost of such a programmer for aliexpress is about 200 rubles.
- Software for the programmer on offsite:
http://www.st.com/web/catalog/tools/FM147/CL1794/SC1807/SS1747/PF210568 (driver and programming software). Link below. (To download, you need to fill out the table and the link will be emailed). - Comb with a pitch of 2.54 mm for programming (it is possible without it, for we use wiring).
Step 1. We connect the programmer to the programming connector on the W1209 board. Signed on the programmer:
- RESET
Step 2 We start the program ST-Link Visual Programmer, set the programming parameters:
Step 3. Do not apply +12v to the board! Power off ST Link. Connect programmer to USB.
Step 4. Try to read the data. If an error occurs, the chip is read/write protected. It is necessary to unlock: the options tab, the first is the program, the second is its industry, the third is the option bytes (we need the third one below), switch to it and make a write page.
Attention! Now old firmware ERASED!
Step 5. Now we write new firmware. File - open - unpacked from the archive (taken from user comments). Press - Program - All Tabs.
For reliable long-term operation of the thermostat at a load of more than 300W, it is better to use a powerful intermediate relay or triac. 
To make a homemade incubator, I needed to purchase a temperature controller. The requirements for it were as follows: small dimensions, low cost, power supply from 12 V DC, powerful executive relay (to withstand a significant load), indication of readings, parameter setting with control buttons, accuracy of temperature measurement and maintenance set parameters and of course reliability.
On the Internet, I came across such a device-. Reviews about it met my requirements. Came to me from the Aliexpress website. This regulator can be used in many places - electric heating, incubators, refrigerators, drying cabinets, water heating systems, protection of electrical equipment, measuring the temperature of the coolant of a car, followed by turning on the fan of the greenhouse, bathhouses, heated floors, heating pipes, etc ... The regulator itself consists of an electronic board with 3 control buttons installed: SET The SET button is used to select the mode and set the parameters, and the and buttons can directly change the data of the programmable parameters. The LED indicator has three digits. The temperature meter itself is based on a thermometer installed in a case and has a wire length of 30 cm.
The control limits lie in the zone from -50.0 to 110.0 degrees. You can connect loads up to 15 A (at 12 V DC) and up to 5 A (when the load is powered from 220 V mains)
The device is powered by 12 -14 V DC. The measurement accuracy is within 0.1 Celsius. The current consumption of the regulator is 35 mA when the relay is operating: 65 mA. In my article I will tell you how to set up and upgrade this thermostat a little.
The process of setting up the W1209 thermostat is shown in the video:
List of tools and materials
- knife or scissors;
-screwdriver;
- soldering iron;
-tester;
- a plastic tube from ear sticks or a fountain pen rod;
-faulty LED with a diameter of 5 mm - 4 pieces;
- plastic racks-4 pcs;
- connecting wires;
- 12 V power adapter;
- screws;
- a plastic box from under screws with a transparent cover;
-adhesive tape.
Step one. Case manufacturing.
The disadvantage of the board is that it is not suitable for installation in a housing, the buttons and indicator are located below the relay and terminals.
Craftsmen arrange the board of this regulator in different ways - who cut out windows in the case for indicators, relays, connectors, some solder the buttons and the indicator, then mount them separately. But I decided to install the board in a transparent case, a box of screws came up.
At first I wanted to paint it by pasting the window for the LED indicator screen. But then he changed his mind and decided to cover it with a self-adhesive film (pieces from the repair remained). It came out quickly and looks good to me. After we make a window in a film for the screen LED indicator and drill holes for buttons
Step two. Installation of the electronic thermostat board.
I installed the thermostat board on racks made of a plastic tube (from a ballpoint pen) as close as possible to the top cover. We make button pushers from a plastic tube from cotton buds or from a ballpoint pen refill. Then at one end of the tube we increase the diameter with a warm soldering iron and put it on the buttons. The tube sat tightly as it expanded with a soldering iron into a cone.
After we close top cover and we insert faulty LEDs on the protruding pushers, after biting off part of the legs - they will be the buttons themselves.
The board has an LED to control the operation of the relay. It was hard to see it from under the cover. I pasted the transparent part of the burned-out LED on it, it became much brighter.
Step three. Checking and adjusting the regulator.
I connected a 12 V adapter to power the thermostat (you can use any 12 V power source and a current of 0.1 A or more). Compare the temperature readings with the reference electronic thermometer, as a result, they were the same.
Setting up the controller is easy. To enter the programming mode, press and hold the SET button for 6 seconds, then adjust with the buttons. To save the setting, press and hold the SET button, or do not touch the buttons for 10 seconds. All thermostat settings will remain in the non-volatile memory of the controller even after turning off the power to the device.
Setting modes.
P0 cooler or heater mode C/H
P1 hysteresis setting 0.1-15 degrees (relay switching mode difference)
P2 set upper operating temperature limit
P3 setting lower operating temperature limit
P4 temperature adjustment
P5 relay activation delay (0-10 sec.,)
P6 emergency overtemperature. The P4 mode is used to adjust the readings according to the reference instrument.
On this, all the finishing touches and alterations are completed. As a result, by mounting the board in a box, we protected the device from moisture, mechanical damage on electronics and did not allow people to be exposed to electric current. After alteration, you can use the thermostat for its intended purpose.
In general, this is a good inexpensive device (100 rubles) with great potential in the field of application.
Temperature controllers are a class of equipment designed to regulate and maintain the temperature in a controlled space within specified limits. They can be used in both heating and cooling applications. These are artificial climate installations, heating systems, freezing equipment.
Mechanical thermostat
According to the principle of operation, thermostats are divided into:
- Mechanical:
- Bimetallic;
- Capillary.
- Electronic:
- With mechanical temperature setting;
- Programmable.
Brief overview of the module
Temperature controller W1209 is a programmable temperature control relay. The sensor included in the delivery set is operational in the temperature range from -50°C to +110°C. The controller is designed to work with heating and cooling equipment up to 1 kVA.
Temperature controller W1209
Technical characteristics of thermostat w1209:
- Controlled temperature range – -50°C – +110°C;
- Measurement accuracy in the range from 9.9°С to 99.9°С - 0.1°С, over the range - 1°С;
- Control accuracy in the range from 9.9°С to 99.9°С - 0.1°С, over the range - 1 °С;
- Hysteresis setting - from 0.1°С to 30°С;
- Supply voltage - 12V;
- Current consumption - 22-72 mA;
- Overall dimensions - 48x40x14 mm;
- Weight - 20 g;
- Permissible operating temperature – -10°C – +60°C.
Note! Some sellers position this device with the name xh w1209. All devices of this type absolutely identical.
Setting and operation of the thermostat
Installing a programmable thermostat W1209 consists in connecting the device to a stabilized power source, setting up a temperature sensor and a controlled circuit.
Important! The fundamental point is that the device contains only “dry” relay contacts, that is, it switches the circuit and does not provide any power to the line.
How to connect an electric heater
For proper operation of the device, you should know the features of its operation:
- It is possible to delay switching on from 0 to 10 minutes;
- The circuit has an adjustable hysteresis. Hysteresis is the temperature difference between turning on and off. This function important for switching heating or cooling devices with high inertia.
Further setting consists in selecting the required parameters using the control buttons and the LED digital indicator.
On the considered w1209 thermostat, the instruction does not give detailed description circuitry, but enthusiasts compiled a fundamental circuit diagram w1209 with a 12 V dc power supply, from which it is clear that the work is controlled by a programmable microcontroller, included according to the standard scheme.
Setting procedure
Read the instruction manual before switching on.
To control settings schemeW1209 provides three buttons:
- "set";
All provided functions and capabilities are configured by pressing the listed buttons.
According to the instructions for W1209, to change the settings, you must enter the programming mode. To do this, press and hold the “Set” button for 5 seconds. When the setting item number appears on the screen, the button can be released. To move through the settings menu, use the "+" and "-" buttons.
Whole thermostat instructionW1209 provides from 6 to 8 positions, depending on current firmware embedded microcontroller:
- P0 - switching control of heating or cooling;
- P1 - adjustment of the hysteresis range;
- P2 - change in the maximum temperature control limit;
- P3 - change in the minimum temperature control limit;
- Р4 – correction of temperature measurement error;
- P5 - programming the turn-on delay time;
- P6 - alarm (not used in most firmware);
- P7 - forced shutdown when the upper control threshold is reached;
- P8 - reset to factory settings (does not work on all firmware).
By default, when entering the programming mode, the first menu item is set to P0.
Location of terminals and controls
Having entered the desired item, use the "+" or "-" buttons to set the required parameter value. To exit the programming mode, press and hold the Set button for 5 seconds. Exit to the mode of operation with the recording of settings also occurs after 10 seconds, if no button has been pressed during this time.
The instruction for the w1209 dc 12 v thermal relay informs that this device has a malfunction alarm, which is displayed on the indicator:
- LLL - open temperature sensor;
- 110 or HHH - short circuit of the sensor loop;
- 888 - sensor malfunction.
In addition to using the programming mode, a factory reset can be performed as follows:
- Remove power from the regulator;
- Press the "+" and "-" buttons simultaneously;
- Turn on the power.
Thermal relay calibration W1209
Calibration of the thermal relay is carried out in the programming mode in the menu item P4. For calibration, you need to have an exemplary thermometer. Comparing the readings of the standard with the readings of the structure, they lead to the same values by manipulating the "+" or "-" buttons. After exiting the settings, W1209 automatically corrects the measurement temperature in the entire range.
In the absence of a thermometer, you can use the known values:
- Snow melting temperature - 0°С;
- The boiling point of water is 100°C.
Important! To reduce the error during the calibration process, it is required to use distilled water.
For domestic use, the error will be within acceptable limits when calibrated with boiled water instead of distilled water.
Do-it-yourself modernization of the W1209 thermostat module
The design of the device provides ample opportunities for modernization. You can modify the device as follows:
- Place the thermostat in the housing;
- Extend the temperature sensor cable;
- Change firmware version.
The last point can be performed if you have the skills to work with programmable controllers. For this purpose, the ST-Link V2 USB programmer is used. The required firmware version can be downloaded from the official website of the controller manufacturer. Redesigning the device by changing the firmware to a newer one allows you to introduce new functions and improve performance.
Hull variant
Improvement of the loop makes sense due to the short length of the standard sensor wire (about 0.5 m).
Setting the temperature corrector
The thermostat temperature corrector is set during instrument calibration. The essence of the corrector is to change the measured values in accordance with the actual temperature indicators.
Video