The thermostat is called the device maintaining temperature in any volume of a constant. The exact thermostats stabilizing temperature to degree shares are difficult and expensive. If so high precision is not required, the thermostat can be and self-made.
It is required to you
- Thermoresistor
- Details for production of the thermostat
- Soldering iron, solder and neutral gumboil
- The power supply on 12 V
- Heater
- Control thermometer
Instruction
1. The principle of operation of the thermostat consists in the following. Right after turning on of the device it gives food on the heater. The signal from the sensor of temperature is given on one entrance of the comparator, its second entrance is connected to the regulator. When temperature exceeds set, logical unit at the output of the comparator will be replaced by zero, and the transistor key will remove food from the relay operating the heater. It will begin to cool down and when temperature is lower set, the comparator will give logical unit on a transistor key again. The heater will turn on and process will repeat. The lag effect of the heater provides a thermostat hysteresis.
2. Find the reference to the description of the self-made thermostat at the end of this article. Open it in a separate tab of the browser. If any from necessary details for assembly of the thermostat at you do not appear, get them.
3. Collect the electronic block of the thermostat, but do not connect the heater to it yet. Give on it food. Heating and cooling a termotezistor, make sure that at at achievement of a certain temperature there is an operation of the relay. Rotating the variable resistor, check whether changes at change of provision of its cursor a threshold of operation of the thermostat.
4. Place the power supply and the thermostat in the certain isolating building. Take out the thermoresistor and the heater to the room in which temperature needs to be stabilized, on long cords. However, if the thermostat is located in the same room, as the heater, it is possible to place the thermoresistor and near it. But at all not in the case as then it will heat up the power supply. Connect the thermoresistor and the heater to the thermostat.
5. Turn on the thermostat. On the control thermometer make sure that temperature indoors grows. When it reaches a certain threshold, the heater has to will be switched off. After that it has to join and be switched off periodically, and temperature indoors - almost not to change. If this is so, the thermostat works correctly.
6. Change setup of the thermostat. In half an hour take temperature indoors. Make sure that it, respectively changed in that party in which you changed control, and after that ceased to change again, and the heater joins still periodically and switched off.