Transformer Sizing Calculator
Transformer Capacity Sizing
Transformer capacity sizing calculator — considers connected load, diversity factor, future expansion to suggest transformer kVA rating. Includes oil type and dry type comparison.
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Excel
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How to Use
Follow these simple steps to get started
Enter connected load (kW)
Enter diversity factor and power factor
Select future expansion %
View recommended transformer kVA
View oil type vs dry type comparison
Tool Preview
Screenshot will be shown here
Who Needs This
Frequently Asked Questions
Not all loads run at the same time — so actual demand is less than connected load. Typical diversity factor = 0.6-0.8.
Yes, oversized transformer gives low efficiency under no-load condition. Right size is best.
Indoor = Dry type (fire safe), Outdoor = Oil type (cheaper, efficient). Dry type is recommended for RMG factories.
Generally 20-25% future expansion factor is kept.
100, 150, 200, 315, 500, 750, 1000, 1500, 2000 kVA — the nearest standard size is selected.
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