Documentation

Complete formula reference and usage guide for DirencHan calculators.

i Getting Started

DirencHan is a browser-based electronics and electrical engineering calculator suite. All computations execute locally using standard IEEE floating-point arithmetic. No account, installation, or internet connection is required after initial page load.

Tip: Use the language button in the header to switch between English and Turkish. The theme toggle changes between dark and light mode. Both preferences are saved in your browser.

Ω Ohm's Law

V = I × R
V = Voltage (volts), I = Current (amperes), R = Resistance (ohms)

Enter any two of the three quantities and DirencHan computes the third automatically, along with dissipated power.

I = V / R — Current from voltage and resistance R = V / I — Resistance from voltage and current V = I × R — Voltage from current and resistance P = V × I — Power in watts

Example

Given: V = 12 V, I = 2 A
R = V / I = 12 / 2 = 6 Ω
P = V × I = 12 × 2 = 24 W

P Power Calculator

P = V × I = I² × R = V² / R
P = Power (W), V = Voltage (V), I = Current (A), R = Resistance (Ω)

The Power Calculator accepts voltage and current as required inputs, with optional resistance for cross-validation. Results are automatically scaled to mW, W, or kW as appropriate.

→ Resistor Networks

Series Configuration

Rtotal = R1 + R2 + R3 + …
Total resistance is the arithmetic sum of all resistors.

Parallel Configuration

1/Rtotal = 1/R1 + 1/R2 + …
Result is always less than the smallest individual resistor.

For two resistors: Rtotal = (R1 × R2) / (R1 + R2).

Voltage Divider

Vout = Vin × R2 / (R1 + R2)
Classic two-resistor unloaded voltage divider.

Voltage Divider Example

V_in = 12 V, R1 = 10 kΩ, R2 = 4.7 kΩ
V_out = 12 × 4700 / (10000 + 4700) = 3.837 V

C Capacitor Calculator

XC = 1 / (2πfC)
Capacitive reactance in ohms. Decreases with increasing frequency.
RC Time Constant τ = R × C (seconds) Stored Energy E = ½CV² (joules) Charge Q = C × V (coulombs) RC Cutoff Freq. fc = 1/(2πRC) (hertz)

L Inductor Calculator

XL = 2πfL
Inductive reactance in ohms. Increases with increasing frequency.
RL Time Constant τ = L / R (seconds) Stored Energy E = ½LI² (joules) Voltage (induced) V = L × dI/dt (volts)

AC AC Circuits

Z = √(R² + X²)   |   X = XL − XC
Impedance Z in ohms, net reactance X = XL − XC
Phase Angle φ = arctan(X / R) (degrees) Power Factor PF = cos(φ) = R / Z Apparent Power S = V × I (VA) Real Power P = S × PF (W) Reactive Power Q = S × sin(φ) (VAR)
A power factor greater than 0.95 is considered excellent.

D LED Resistor Calculator

R = (Vs − n × Vf) / If
Vs = supply, Vf = forward voltage per LED, If = forward current, n = LEDs in series
LED Color Typical Vf Typical If
Red / Yellow1.8 – 2.2 V20 mA
Green2.0 – 2.5 V20 mA
Blue / White / UV3.0 – 3.5 V20 mA
Infrared (IR)1.2 – 1.5 V20 mA

W Wire Size Calculator

Calculates the minimum AWG copper conductor required to carry the specified current while keeping voltage drop within the stated limit.

Standard practice: keep voltage drop to 3% or less for branch circuits, 5% or less for feeder conductors.

R References & Standards

  • IEEE Standard 519 — Harmonic Control in Electric Power Systems
  • NFPA 70 (NEC) — National Electrical Code, wire ampacity tables
  • IEC 60038 — Standard Voltages
  • Boylestad & Nashelsky, Electronic Devices and Circuit Theory
Safety Notice: All calculations are for informational and educational purposes. Verify all results with certified instruments.