13. About the Decibel
The decibel is the unit of bell(B) with an auxiliary unit of deci (d) which means 1/10. The definition of bell is “logarithm of the ratio of a phisical quantity relative to a specified or implied reference level” generally it requires two values.
Decibel value of electric power |
The decibel value is calculated by the following formula when the measured electric power is Wm and reference electric power is Wb. decibeldB: ![]() |
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Decibel value of voltage |
The decibel value is calculated by the following formula when measured electric voltage is Vm and reference electric voltage is Vb. DecibeldB: ![]() *Relations between voltage and electric power are square, it is multiplied by 20 which is 2 times of 10 since it takes the logarithm. |
Decibel value of electric current |
The decibel value is calculated by the following formula when the measured electric current is Im and reference electric current is Ib. DecibeldB: ![]() *Relations between current and electric power are square, it is multiplied by 20 which is 2 times of 10 since it takes the logarithm. |