Calculation
Ltotal = L1 + L2 (+ L3)
With no magnetic coupling, inductances of series-connected coils add directly, as with resistors.
Busch 2006, Abschnitt 2.6.1, Gl. (2.52)
Inductors in series (uncoupled)
With no magnetic coupling, inductances of series-connected coils add directly, as with resistors.
MINTSI
02
Result
Select a target and calculate.
Understand the inputs
- Total inductance Ltotal — Inductance of the complete series chain with no mutual coupling.
- Inductance L1 — First inductor in the series chain.
- Inductance L2 — Second inductor in the series chain.
- Inductance L3 (optional) — Third inductor; set to 0 if only two inductors are present.
Example
10 mH and 22 mH in series give 32 mH.
Assumptions and limits
No magnetic coupling (mutual inductance M=0) and ideal, resistance-free coils; coupling requires additional ±2M terms.
Understand Inductors in series (uncoupled)
This calculator determines the total inductance of two or three magnetically uncoupled inductors connected in series.
What does this quantity describe?
With no magnetic coupling, inductances of series-connected coils add directly: Ltotal=L1+L2(+L3), analogous to resistors in series.
Formula and variables
Ltotal = L1 + L2 (+ L3)
Ltotal = L1 + L2 (+ L3)
| Symbol / input | Meaning |
|---|---|
| Total inductance Ltotal | Inductance of the complete series chain with no mutual coupling. |
| Inductance L1 | First inductor in the series chain. |
| Inductance L2 | Second inductor in the series chain. |
| Inductance L3 (optional) | Third inductor; set to 0 if only two inductors are present. |
Choose the inputs correctly
L1, L2 and optionally L3 are the inductances of the series-connected, uncoupled coils.
How to use the calculator
Take inductance values from a datasheet or measurement; ensure there is no significant magnetic coupling between the coils.
Worked example
10 mH and 22 mH in series give Ltotal=32 mH.
Understand the result and units
Ltotal grows linearly with each added coil; with coupling present, an additional ±2M term would apply.
All inductances are entered in the same or convertible units (H, mH, µH).
Typical applications
Combining available coils into a required total inductance, e.g. in filter circuits or chokes.
Assumptions, limits and common mistakes
No magnetic coupling (M=0) and ideal, resistance-free coils. Real winding resistance and coupling are not included.
Common mistake: Do not assume zero coupling without checking when coils are placed close together or share a common core.
Frequently asked questions
What is “Inductors in series (uncoupled)” used for?
Combining available coils into a required total inductance, e.g. in filter circuits or chokes.
Where do the input values come from?
L1, L2 and optionally L3 are the inductances of the series-connected, uncoupled coils.
What does the result not cover?
No magnetic coupling (M=0) and ideal, resistance-free coils. Real winding resistance and coupling are not included.