Temperature limit fuses Manufacturers online

Temperature fuses (also known as thermal fuses) protect electrical and electronic devices from overheating.

They interrupt the circuit as soon as a certain temperature is reached, thus preventing damage or dangerous situations such as fires.

Below is an overview of the variants and uses of thermal fuses:

Types of thermal fuses:

1. Fusible links (thermal fuses):
These types contain a special solder that melts at a certain temperature and breaks the circuit. They are simple and reliable and are used in many household appliances.

2. Bimetal fuses (thermal cutoffs):
These consist of two different metals that expand differently when heated. At a certain temperature, the bimetal bends and interrupts the circuit. Some bimetal fuses are resettable and can be used again after cooling down.

Use of thermal fuses:

1. Protection of electric motors:
Thermal fuses protect electric motors (e.g. in washing machines, vacuum cleaners, pumps) from overheating due to overload or blocked operation. They switch off the motor before it is damaged by the heat.

2. Overheating protection in transformers and power supply units:
In transformers, power supply units and chargers, thermal fuses prevent overheating that could be caused by short circuits, overload or a defect.

3. Protection of lighting systems:
In lighting systems such as ceiling lights, LED lights and halogen lamps, thermal fuses prevent overheating caused by defective components or unfavorable ambient conditions.

4. Battery and rechargeable battery packs:
In rechargeable batteries and battery packs (e.g. for laptops, smartphones or electric vehicles), thermal fuses prevent overheating that can occur due to short circuits, overcharging or malfunctions.

5. Heaters and electric heating systems:
In electric heating systems, such as underfloor heating or radiant heaters, they serve as a safety mechanism to prevent overheating due to malfunctions or insufficient ventilation.

6. Electronic circuits and semiconductor devices:
Protecting sensitive electronic components such as microprocessors, power transistors and amplifiers from thermal damage.

7. Overheating protection in household appliances:
In appliances such as coffee makers, hair dryers, kettles, microwaves, irons and fan heaters, thermal fuses prevent overheating by switching off the power supply as soon as the set maximum temperature is exceeded.

Advantages of thermal fuses:

• Thermal fuses provide reliable protection against overheating.
• They are inexpensive and easy to integrate into electrical circuits.
• They can be used in a wide range of devices and systems, from simple household appliances to complex industrial applications.

Thermal fuses are crucial for the safety and longevity of electrical and electronic devices, as they effectively protect against overheating and the resulting damage.

Here is an overview of the most important criteria to consider when purchasing thermal fuses:

When buying thermal fuses, there are a number of criteria you should consider to ensure that the fuse is suitable for the application in question.

• The nominal cut-off temperature is the temperature at which the thermal fuse interrupts the circuit. This temperature must be selected so that it is safely below the maximum permissible temperature of the protected device or component. usual values range from 70°C to 250°C. Select the appropriate rated cut-off temperature based on the maximum permissible operating temperature of the appliance.
• Current carrying capacity indicates how much current the fuse can withstand before it blows or trips. Ensure that the fuse is rated for the maximum current flowing through the protected circuit. This value is given in amperes (A) and must match the specific application.
• Most thermal fuses are single-trip fuses (non-resettable). After tripping, they must be replaced. However, there are also resettable fuses (e.g. bimetal fuses) that reset themselves after cooling down. Select the type of fuse based on the application:
• One-time fuses are suitable for critical applications where permanent protection against overheating is required.
• Resettable fuses are suitable for applications where frequent temperature peaks occur that do not require permanent shutdown.
• The design and size must match the installation situation and the available space. Thermal fuses are available in various shapes (e.g. cylindrical, flat, radially wired). Choose a design that can be easily integrated into the circuit or device.
• The response time indicates how quickly the fuse reacts to a change in temperature. In applications where a fast response is required to prevent damage (e.g. in high-performance devices), a fuse with a short response time should be selected.
• Consider the environmental conditions under which the thermal fuse will operate:
• Choose thermal fuses that are protected against moisture and corrosion if they will be used in humid or corrosive environments.
• In environments with strong vibrations or mechanical loads, the fuse should be robust and shock-resistant.
• Pay attention to the electrical insulation of the fuse, especially in applications with high voltages.
• Pay attention to the quality and reliability of the fuse. Choose products that comply with the applicable standards and certifications (e.g. UL, VDE, IEC). This ensures a high level of reliability and safety during operation.
• Check the service life and ageing characteristics of the fuse. Some fuses can lose their properties over time or through repeated loading. For long-term applications, you should look for long-life fuses with a low ageing tendency.
• Ensure that the thermal fuse is compatible with the specific application, including the electrical system and electrical requirements of the appliance in which it will be used.
• Consider the cost of thermal fuses and their availability on the market. High-quality and certified fuses can be more expensive, but also offer more safety and reliability. Also check if the fuse is available in bulk in case you need to replace it regularly.
• Pay attention to the packaging size and storage options, especially if you buy the fuses in large quantities. Some thermal fuses are sensitive to moisture or need to be stored under certain conditions.
• Consider special requirements such as the need for a thermal connection (e.g. thermal paste or special terminals) or integration into existing circuits and assemblies.

By taking these factors into account, you can ensure that the selected thermal fuse reliably fulfills the required protective functions and guarantees the safety and longevity of the device or application.

Thermal fuses can be purchased from various suppliers. You will find comprehensive information on manufacturers and suppliers of thermal fuses around the world on Exportpages.