Home
Back
Full Load Current Formula (3-Phase):
| From: | To: |
Full Load Current (FLC) is the maximum current that an electrical device or system draws when operating at its rated capacity. For three-phase systems, it's calculated using apparent power (kVA), voltage, and power factor.
The calculator uses the 3-phase Full Load Current formula:
Where:
Explanation: The formula converts kVA to VA (by multiplying by 1000), then divides by the product of voltage, square root of 3 (for three-phase systems), and power factor to obtain the current in amperes.
Details: Accurate FLC calculation is crucial for proper electrical system design, circuit breaker sizing, cable selection, and ensuring equipment operates within safe current limits without overheating or causing voltage drops.
Tips: Enter apparent power in kVA, voltage in volts, and power factor as a decimal between 0 and 1. All values must be positive numbers greater than zero.
Q1: What's the difference between single-phase and three-phase FLC calculation?
A: For single-phase systems, the formula is \( FLC = \frac{kVA \times 1000}{V \times PF} \) without the \( \sqrt{3} \) factor.
Q2: Why is power factor important in FLC calculation?
A: Power factor accounts for the phase difference between voltage and current. Lower power factor means higher current is required to deliver the same real power.
Q3: What are typical power factor values?
A: Power factor typically ranges from 0.7 to 1.0. Industrial loads often have 0.8-0.9 PF, while heavily inductive loads can have lower values.
Q4: How does voltage affect full load current?
A: Higher voltage results in lower current for the same power level, which is why high-voltage transmission is used for long-distance power delivery.
Q5: When should this calculation be used?
A: This calculation is essential for electrical engineers, technicians, and designers when sizing components for motors, transformers, generators, and other three-phase electrical equipment.