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Calcimator

Transformer Sizing Calculator

Size single-phase and three-phase transformers: calculate required KVA, full load current, and select next standard size.

Inputs

V
A
phase

Results

Required KVA

156.5 kVA

Next Standard Size

167 kVA

Full Load Current188.24 A
Percent Loading85%
How to Use This Calculator
  1. Enter the System Voltage in volts — this is the transformer's secondary (output) voltage.
  2. Enter the Total Load Current in amperes — sum all connected loads on the secondary.
  3. Set the Power Factor for the load mix: 0.80–0.95 is typical for industrial and commercial applications.
  4. Set the Demand Factor — the ratio of maximum expected demand to total connected load (0.6–0.9 for most applications).
  5. Select the Number of Phases (1 for single-phase, 3 for three-phase).
  6. Read the Required KVA and the Next Standard Size to select the correct transformer from manufacturer catalogs, then review the Percent Loading to ensure the transformer is not oversized.
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