What is tolerance and power rating of resistor?
The power rating of a resistor is the specification given with a resistor that serves to tell the maximum amount of power that the resistor can withstand. Thus, if a resistor has a power rating of 1/4 watts, 1/4 watts is the maximum amount of power that should be fed into the resistor.
What is power rating in resistor?
The power rating of a resistor indicates how much power a resistor can handle before it becomes too hot and burns up. Power is measured in units called watts. The more watts a resistor can handle, the larger and more expensive the resistor is. Most resistors are designed to handle 1/8 W or 1/4 W.
What does the resistor tolerance mean?
Tolerance is the percentage of error in the resistor’s resistance, or how much more or less you can expect a resistor’s actual measured resistance to be from its stated resistance. A gold tolerance band is 5% tolerance, silver is 10%, and no band at all would mean a 20% tolerance.
Why does a resistor have tolerance?
Some projects require your measurements to be more precise than others, and for this reason the tolerance band is useful in identifying which resistor will give you a more accurate resistance reading. The smaller the tolerance percentage is, the higher the precision in your measurements.
Why is power rating important?
Resistor power rating is an important parameter to consider when choosing a resistor for a particular application. The job of a resistor is to resist current flow through a circuit and it does this by dissipating the unwanted power as heat.
How do you determine tolerance?
Tolerance Calculation Formulas
- c = a – b. Upper limit dimension of the closing element:
- c max = a max – b min Lower limit dimension of the closing element:
- c min = a min – b max Tolerance of the closing element (subtracting equation 3 from equation 2)
- c max – c min = a max – a min – (b min – b max )
- T c = T a + T b
How do you determine the power rating of a resistor?
A resistor’s power rating can usually be deduced by observing its package size. Standard through-hole resistors usually come with ¼W or ½W ratings. More special purpose, power resistors might actually list their power rating on the resistor. These power resistors can handle a lot more power before they blow.
How do you calculate the power of a resistor?
Power can also be calculated using either P = IV or P=V2R P = V 2 R , where V is the voltage drop across the resistor (not the full voltage of the source). The same values will be obtained.
Why is resistor tolerance important?
The tolerance of a resistor tells you how far, in percentage, from its nominal value the actual measured resistance of that resistor may be.
What is resistor power rating and why is it important?
Resistor power rating can be defined as the maximum power a resistor can handle safely without any damage. We know that, resistor dissipates the excess energy in form of heat. Power rating indicates the maximum heat a resistor can dissipate safely.
What is tolerance in resistor?
Resistor Tolerance. The tolerance of a resistor is the deviation that a resistor may vary from its nominal value resistance, measured at 25°C with no load applied. In other words, the resistor tolerance is the amount by which the resistance of a resistor may vary from its stated value.
What are the tolerance series of preferred values?
The tolerance series of Preferred Values shown above are manufactured to conform to the British Standard BS 2488 and are ranges of resistor values chosen so that at maximum or minimum tolerance any one resistor overlaps with its neighbouring value. For example, take the E24 range of resistors with a 5% tolerance.
What is the importance of resistor color codes?
Resistor color codes helps to read resistance, tolerance and voltage. Other than these three values, there is another important parameter required, for using the resistor in a circuit. This is power rating of a resistor.It is very important to use correct power rated resistor in the circuit to prevent the circuit from damaging.