1. What is Transformer Capacity?

Transformer capacity, measured in volt-amperes (VA), represents the maximum load a transformer can handle. It's calculated by multiplying the voltage (V) by the current (I) that the transformer can deliver.

2. How Does the Calculator Work?

The calculator uses the basic power equation:

Where:

• \( V \) — Voltage in volts
• \( I \) — Current in amps

Explanation: This simple formula gives the apparent power of the transformer, which is the product of the voltage and current it can supply.

3. Importance of Capacity Calculation

Details: Proper transformer sizing is crucial for electrical system design. Undersized transformers may overheat and fail, while oversized ones are inefficient and costly.

4. Using the Calculator

Tips: Enter the transformer's rated voltage and current values. Both values must be positive numbers for accurate calculation.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between VA and watts?
A: VA (volt-amperes) measures apparent power, while watts measure real power. They're equal only for purely resistive loads.

Q2: How do I account for three-phase transformers?
A: For three-phase, multiply by √3 (1.732) for line-to-line voltage: Capacity = √3 × V × I.

Q3: What safety factor should I use?
A: Typically 1.25-1.5 times the calculated load to allow for future expansion and prevent overheating.

Q4: How does temperature affect capacity?
A: Higher temperatures reduce capacity. Manufacturers provide derating factors for different ambient temperatures.

Q5: Can I use this for DC transformers?
A: This calculation works for DC, but most transformers are AC devices. For DC, you'd typically use a switching power supply.