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Calculadora de Limitador de Corriente de Irrupción

Calcula los componentes necesarios para limitar la corriente de irrupción al encender una fuente de alimentación.

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Fórmula

R_cold = V_s / I_inrush, τ = R_cold × C_f, E = 0.5 × C_f × V_s²

V_sSupply voltage (V)
I_inrushTarget inrush current (A)
C_fFilter capacitance (F)
R_coldNTC cold resistance (Ω)
τTime constant (s)

Cómo Funciona

An inrush current limiter is an electronic component designed to reduce the initial surge of current when a device or circuit is first energized. When electrical equipment is first switched on, it can draw several times its normal operating current, which can stress power supplies, trip circuit breakers, or damage sensitive components. The limiter typically uses a thermistor or other temperature-sensitive resistor that initially has high resistance, which then reduces as the component heats up during the startup phase.

Ejemplo Resuelto

For a 120V AC motor with a typical inrush current of 10A and steady-state current of 2A: Calculate initial resistance needed to limit current. Use formula: R = V/I Initial resistance = 120V / 10A = 12 ohms. After warm-up, resistance drops to approximately 2 ohms, allowing normal current flow. Final calculated power dissipation would be 120W during initial startup, reducing to 28.8W during steady-state operation.

Consejos Prácticos

  • Always select an inrush current limiter with voltage and current ratings matching your specific application
  • Consider thermal characteristics and power dissipation capabilities
  • Use temperature-compensated designs for more stable performance
  • Implement proper heat sinking for high-power applications

Errores Comunes

  • Underestimating peak current requirements
  • Selecting limiters with insufficient power handling capacity
  • Ignoring temperature effects on component performance
  • Failing to account for system-specific startup characteristics

Preguntas Frecuentes

What is the primary purpose of an inrush current limiter?

To reduce the initial high current surge when electrical equipment is first energized, protecting components and preventing potential damage or nuisance tripping.

How do inrush current limiters work?

They typically use thermistors or other temperature-sensitive resistors that start with high resistance and decrease resistance as they warm up, gradually allowing more current to flow.

When should I use an inrush current limiter?

Use in applications with motors, transformers, capacitive power supplies, or any circuit where initial current surge could potentially damage components or cause system instability.

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