1. What is LED Inrush Current?

Inrush current is the instantaneous high input current drawn by LED drivers when first turned on. This surge occurs due to charging of capacitors and can be significantly higher than the steady-state operating current.

2. How Does the Calculator Work?

The calculator uses the LED inrush current equation:

Where:

• \( I_{inrush} \) — Inrush current (amps)
• \( I_{steady} \) — Steady state current (amps)
• \( N_{drivers} \) — Number of LED drivers (dimensionless)

Explanation: The equation accounts for the typical 100x surge current of LED drivers during startup multiplied by the number of drivers in the system.

3. Importance of Inrush Current Calculation

Details: Calculating inrush current is crucial for proper circuit breaker sizing, preventing nuisance tripping, and ensuring the power supply can handle the initial surge without voltage drops.

4. Using the Calculator

Tips: Enter the steady-state current in amps and the number of LED drivers. All values must be valid (current > 0, drivers ≥1).

5. Frequently Asked Questions (FAQ)

Q1: Why is inrush current important?
A: Inrush current can cause circuit breakers to trip, damage contacts, and lead to voltage sags affecting other equipment.

Q2: How long does inrush current last?
A: Typically lasts from a few milliseconds to several cycles (usually less than 100ms).

Q3: Can inrush current be reduced?
A: Yes, through inrush current limiters, soft-start circuits, or staggered startup of drivers.

Q4: Is this calculation conservative?
A: Yes, it provides a worst-case estimate assuming all drivers experience inrush simultaneously.

Q5: Does temperature affect inrush current?
A: Yes, cold temperatures can increase inrush current due to higher capacitor ESR.