A resistor is an electronic component used to limit current or voltage, usually made of conductor material. It serves to impede the passage of current, thereby controlling the potential difference and the magnitude of current in a circuit.
Resistance has the size of the points, its unit is Ω, except Ω in addition to kΩ, MΩ, the conversion relationship between them is:
1kΩ = 1000Ω; 1MΩ = 1000kΩ.
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Letter |
C |
S |
N |
W |
T |
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Types of Resistors |
Solid |
Oxide Film Resistors |
Metal Oxide Film Resistors |
Clinker |
Fusible Resistors |
According to the different size of resistance value, resistors can be divided into two types: fixed resistors and variable resistors. Among them, fixed resistors can be divided into cylindrical, square, flat round and other types according to its shape; variable resistors include potentiometers, sliding varistors and so on.
When the current through the resistor, will produce a certain amount of heat, this is because the resistor on the current obstruction leads to the process of electrical energy into heat.
Therefore, under certain conditions, the higher the current through the resistor, the more heat is generated.
The parameters of resistors mainly include nominal resistance value, power rating, operating temperature range, etc.. Among them, the nominal resistance value refers to the resistor in the standard working condition can achieve the resistance value; rated power refers to the resistor can withstand the maximum operating power; operating temperature range refers to the temperature range of the resistor can work normally.
IV. the use of resistors precautions
In the use of resistors need to pay attention to the following points:
1. Select the appropriate resistance value: According to the size of the required current and voltage in the circuit, select the appropriate resistance value to ensure the stability and safety of the circuit.
2. Pay attention to heat dissipation: As the resistor will generate a certain amount of heat when working, it is necessary to take appropriate measures to dissipate heat in order to avoid overheating damage to the resistor or other circuit components.
3. Avoid overloading: If too large a load is connected to the resistor, it may cause the resistor to overheat or even burn out. Therefore, you need to make sure that the resistor is within its power rating when using it.
4. Regular inspection and maintenance: In order to prolong the service life of the resistor and ensure its normal working condition, you need to regularly inspect and maintain the resistor's appearance, electrical performance and other aspects.
