(without magnetic coupling)
The equivalent inductance (L) is calculated by the next formula:
Formula 1
L = L1 + L2 + L3 + … + Ln
Where:
L is the equivalent inductance in henry (H)
L1, L2, L3...Ln are associated inductances in henry (H)
Note: Submultiples of the henry (uH or mH) can be used.
Formula 2
If the associated coils (n) have the same inductances the becomes.
L = n x L1
Data:
L is the equivalent inductance in henrys (H)
n is the number of associated coils
L1 is the value of one of the associated coils in henry (H)
Application Example:
Coils with inductances of 10 mH, 20 mH and 50 mH are wired in series. What is the equivalent inductance?
Note: Henry´s submultiples can be used, but be sure that all the elements are expressed in the same submultiple and the result also.
Data:
L1 = 10 mH
L2 = 20 mH
L3 = 50 mH
L = ?
Applying fórmula.1:
L = 10 + 20 + 50 = 80 mH