The development of technical means has allowed people to improve the quality of their lives everywhere. Therefore, today everyone can press a button and set the desired temperature range in the room. In this case, it is no longer necessary to constantly control the fuel supply using a switch, since this function is performed by a thermostat with an air temperature sensor. We will consider how to connect this device in this article. So let's get started!
In practice, there is a fairly large assortment of wiring diagrams for thermostats with an air temperature sensor. The main differences are determined not only by the type of device, but also by the features of the heating equipment. So, the simplest connection scheme is considered to be a direct connection to a 230 V circuit.
In this case, power is supplied directly from the phase and neutral conductors or from the contacts of the outlet, depending on the design of the device. This arrangement is suitable for low power heaters where the threat from emergency operation is relatively small. In other cases, it is more practical to use a scheme with the installation of a separate machine for powering a heating boiler or refrigeration unit.
As you can see in the diagram, the phase and neutral conductors are connected to the switchboard, which are connected to the UDT differential current device. Then the neutral conductor N is directly output to the terminal of the thermostat 4, and the phase L through the AB circuit breaker to pin 5 is the power circuit. From terminals 3 and 6 of the thermostat, power is supplied to the electrical heating element. An air temperature sensor is connected to terminals 1 and 2.
To supply power industrial heating devices, use a power circuit with a contactor:
As in the previous version, the thermostat is powered through the automatic switch AB and UDT to terminals 5 and 6. But the load power pins 3 and 4 are connected to the control circuit of the contactor A1 and A2. The heating element itself is powered from the mains through the outputs of the contactor 2 and 4, bypassing the thermostat. Such a scheme is recommended for all cases of power supply to a load exceeding 2/3 of the nominal value of the thermostat.