Inductor Time Constant Calculator

Calculate the RL time constant for an inductor-resistor circuit.

mH
Ω

Time Constant (tau)

0.001000 s

Time Constant (ms)1.000 ms
Settling Time (5 tau)5.000 ms

Time Constant (tau) vs Inductance

RL Time Constant

tau = L / R

Current in an RL circuit rises to 63.2% of final value in one tau. After 5 tau, current is at ~99.3% of steady state.

Example Calculation

100 mH inductor with 100 ohm resistance.

  1. 01tau = 0.1 / 100 = 0.001 s = 1 ms
  2. 025 tau = 5 ms to reach steady state

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A complete guide to Ohm's Law. Learn the relationship between voltage, current, and resistance, with practical examples, the power triangle, and circuit analysis tips.

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