1. What Is The Transformer Sizing Formula?

The transformer sizing formula calculates the required kVA rating based on the load current and voltage. It provides an accurate assessment of the transformer capacity needed for a given electrical load.

2. How Does The Calculator Work?

The calculator uses the transformer sizing formula:

Where:

• \( I \) — Current in amperes (A)
• \( V \) — Voltage in volts (V)
• 1.732 — Constant for three-phase systems (√3)
• 1000 — Conversion factor to kVA

Explanation: The formula accounts for the three-phase power calculation, converting the product of current and voltage to kVA rating.

3. Importance Of Transformer Sizing

Details: Proper transformer sizing is crucial for efficient power distribution, preventing overload conditions, ensuring system reliability, and optimizing energy efficiency.

4. Using The Calculator

Tips: Enter current in amperes and voltage in volts. All values must be valid (current > 0, voltage > 0).

5. Frequently Asked Questions (FAQ)

Q1: Why use 1.732 in the formula?
A: 1.732 (√3) is used for three-phase power calculations to account for the phase difference in three-phase systems.

Q2: What are typical transformer size ranges?
A: Transformer sizes typically range from small units (5-25 kVA) for residential use to large units (1000+ kVA) for industrial applications.

Q3: When should transformer sizing be calculated?
A: Transformer sizing should be calculated during electrical system design, when adding new loads, or when upgrading existing power systems.

Q4: Are there limitations to this formula?
A: This formula provides basic sizing for balanced three-phase loads. Additional factors like load diversity, future expansion, and power factor should be considered for precise sizing.

Q5: Should derating factors be applied?
A: Yes, derating factors for ambient temperature, altitude, and harmonic content should be considered for accurate transformer selection.