HaruTools Lab | Free Online Utility Tools

RLC Circuit Impedance Calculator

Instantly calculate AC impedance and vector diagrams

AdvertisementYour Ad Code Here

Input Parameters

[V]
[Hz]
[Ω]
[mH]
[μF]
Impedance Z-
Phase Angle θ -
Circuit Current I-
Resonant Freq f₀-
Disclaimer & Notice
  • This tool calculates theoretical values based on ideal components (R, L, C). Actual components include parasitic elements like DCR (Inductor) or ESR (Capacitor).
  • In high-frequency ranges, stray capacitance and inductance from wiring may affect results. Physical layout impacts the total impedance.
  • HaruTools Lab is not responsible for any losses, circuit damage, or injuries resulting from the use of this tool. Always verify designs with measurement equipment like network analyzers.

Vector Diagram (Auto-Scaling)

AdvertisementYour Ad Code Here

What is an RLC Circuit Impedance Calculator?

In AC circuits, Impedance (Z) represents the total opposition to alternating current, combining Resistance (R), Inductance (L), and Capacitance (C). This tool is an online simulator that calculates impedance, current, phase difference, and resonant frequency for series and parallel circuits, providing visual vector diagrams for better understanding.

1. Series Circuit Impedance Formula

In a series circuit, the same current flows through all components. The impedance $Z$ is calculated using the following formula:

$$Z = \sqrt{R^2 + (X_L - X_C)^2} \quad [\Omega]$$

Where $X_L = 2\pi f L$ is inductive reactance and $X_C = \frac{1}{2\pi f C}$ is capacitive reactance. The phase angle $\theta$ is $\tan^{-1}(\frac{X_L - X_C}{R})$.

2. Parallel Circuit Admittance Calculation

In a parallel circuit, the same voltage is applied across components. It is easier to use Admittance (Y), the reciprocal of impedance.

$$Y = \sqrt{(\frac{1}{R})^2 + (\frac{1}{X_C} - \frac{1}{X_L})^2} \quad [S]$$ $$Z = \frac{1}{Y} \quad [\Omega]$$

3. What is Resonant Frequency (f₀)?

Resonance occurs when inductive reactance and capacitive reactance cancel each other out, making the circuit purely resistive.

$$f_0 = \frac{1}{2\pi \sqrt{LC}} \quad [Hz]$$

In series resonance, impedance is minimized (current is maximized). In parallel resonance, impedance is maximized (current is minimized).

Features

Frequently Asked Questions (FAQ)

Q. What is the difference between "Lagging" and "Leading" current?

A. If the circuit is inductive (L is dominant), the current lags behind the voltage (Lagging). If it is capacitive (C is dominant), the current leads the voltage (Leading).

Q. Do I need to convert units?

A. No, you can input inductance in mH and capacitance in μF directly. You can also switch to direct reactance (Ω) input.

Related Tools

AdvertisementYour Ad Code Here