Emirates Transformer & Switchgear

    Transformer Sizing Guide — How to Select the Right Capacity

    Engineering guide to selecting the correct transformer size. Covers load analysis, voltage class, environment, cooling and insulation fluid selection.

    5-Step Transformer Sizing Methodology

    Sum all connected loads in kW, apply diversity factors (typically 0.6–0.8 for commercial, 0.4–0.6 for residential), and convert to kVA using the expected power factor. Include future expansion margin of 15–25%.

    Full Guide

    Quick Reference — Typical Sizing by Application

    These are indicative configurations. Actual sizing requires detailed load study and site assessment.

    ApplicationRecommended SizeVoltageCoolingProduct
    Residential Complex (200 units)2 × 1,000 kVA11/0.4 kVONANDistribution
    Commercial Tower (30 floors)2 × 2,500 kVA11/0.4 kVONAN/ONAFDistribution
    Shopping Mall (50,000 m²)3 × 2,000 kVA11/0.4 kVONANPackage Substation
    Data Centre (5 MW IT Load)4 × 2,000 kVA Dry-Type11/0.4 kVAN/AFCast Resin Dry-Type
    Solar PV Plant (50 MWp)2 × 40 MVA33/132 kVONAN/ONAFSolar PV / GSU
    Industrial Factory1 × 5 MVA11/0.4 kVONANMedium Power
    Oil & Gas Facility2 × 10 MVA (ATEX)33/11 kVKNANOil & Gas
    Wind Farm (30 MW)1 × 50 MVA33/132 kVONAN/ONAFSolar PV / GSU
    Battery Storage Site (50 MWh)2 × 25 MVA33/132 kVONANBESS
    Power Plant Step-Up (200 MW)1 × 250 MVA15.75/400 kVODAFGSU
    EHV Transmission Substation2 × 315 MVA400/220 kVODAFEHV Power
    Electrolysis / Smelter (10 MW)2 × 12.5 MVA33/0.8 kVOFAFRectifier

    Related Resources

    01

    FAQ

    Answers to common questions about transformers, ordering and standards.

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    03

    Standards

    IEC vs IEEE vs UL — side-by-side comparison.

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    05

    Compliance

    Regional regulatory requirements across key markets.

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