Cement resistor, is the use of cement (in fact, not cement but refractory mud, this is commonly known as) sealed resistor, that is, the resistance wire wound in non-alkaline heat-resistant porcelain pieces, with heat-resistant, moisture-resistant and corrosion-resistant material protection fixed, and wire wound resistance body into the square porcelain frame, with special non-combustible heat-resistant cement filling and sealing. Cement resistors include ordinary cement resistors and cement wire-wound resistors. The shape of cement resistor is shown. Cement resistor is a kind of wire-wound resistor, it belongs to the resistance of high power, can allow the passage of large current. Its role is the same as the general resistance, but can be used in large current occasions, such as series and motor, limit the motor starting current, resistance value is generally not big. Cement resistor has a large size, shock resistance, humidity resistance, heat resistance and good heat dissipation, low price and other characteristics, widely used in power adapters, audio equipment, audio frequency divider, instruments, meters, TV, cars and other equipment.
characteristic
1, shock resistance, humidity resistance, heat resistance and good heat dissipation, low price and other characteristics.
2, completely insulated, suitable for printed circuit board.
3. Wire wound on porcelain rod and welding joint to produce accurate resistance value and prolong life.
4. High resistance value is made of metal oxide membrane (MO) instead of winding.
5, excellent heat resistance, small resistance temperature coefficient, linear change.
6, short time overload resistance, low noise, resistance value for years without change.
7, good explosion-proof performance, play a protective role.
Cement resistance is usually used for large power, large current occasions, there are 2W, 3W, 5W, 10W or even greater power, such as air conditioning, television, and other power in the hundred watt level of electrical appliances, basically will use cement resistance.
The shortcoming of cement resistance is that it is large in size, high in heat when used, easy to distribute, precision often cannot meet the requirements of use, stability and so on. Cement resistance shell is generally made of ceramic, its main composition is: alumina Al2O3, commonly known as corundum porcelain, with fast heat dissipation, high strength characteristics.