What is the Role of Thermal Fuse in the Circuit?
Thermal fuse is also called thermal fuse, it is a new type of electrical overheating protection element. This kind of component is usually installed in heat-prone electrical appliances. Once the electrical appliance fails to generate heat, when the temperature exceeds the abnormal temperature, the thermal fuse will automatically fuse to cut off the power supply to prevent the electrical appliance from causing a fire. In recent years, all household appliances whose main function is to generate heat, such as rice cookers, electricity hoppers, electric stoves, etc., have been installed with thermal fuses, which can cut off the power supply in time when the internal parts of the machine fail to prevent further damage to the electrical appliances. , Also put an end to the fire caused by this. The thermal fuse is the same as the fuse we are familiar with. It is usually only used as a power path in the circuit. If it does not exceed its rated value during use, it will not fuse and has no effect on the circuit. It will fuse and cut off the power supply circuit only when the electrical appliance malfunctions and produces an abnormal temperature.
This is different from a fuse fuse, which is blown by the heat generated when the current exceeds the rated current in the circuit.
Thermal fuse has the characteristics of accurate melting temperature, high withstand voltage, small size and low cost. The rated temperature and rated current are marked on the housing of the thermal fuse, so it is not difficult to identify and it is very convenient to use. It can be widely used in electrical equipment, electric heating equipment and practical electrical appliances for overheating protection.
The thermal fuse mainly has the following parameters:
①Rated temperature: Sometimes called the operating temperature or the fusing temperature, it refers to the temperature at which the temperature rises to the fusing temperature at a rate of 1°C per minute under no-load conditions.
②Fusing accuracy: refers to the difference between the actual fusing temperature of the thermal fuse and the rated temperature.
③Rated current and rated voltage: Generally, the nominal current and voltage of thermal fuse have a certain margin, usually 5A and 250V.
Thermal fuse is a one-time-use protection element. Its use effect not only depends on the performance of the element itself, but more importantly, how to select and install the thermal fuse correctly. The thermal fuse is generally connected in series in the circuit when it is used. Therefore, when choosing a thermal fuse, its rated current must be greater than the current used in the circuit. Never allow the current through the thermal fuse to exceed the specified rated current. Before selecting the rated temperature of the thermal fuse, you must understand and actually measure the temperature difference between the temperature to be protected and the location where the planting fuse is installed. In addition, the length of the fusing time and the availability of ventilation are also closely related to the selection of the rated temperature of the thermal fuse.
