Oil-Immersed Transformers

S□-M Oil-Immersed Power Transformer

Sealed mineral-oil distribution transformers, 30–2500 kVA at 10/10.5 kV — grain-oriented core with multi-step 45° mitred joints, corrugated tank breathing with the oil, maintenance-free with no oil change.

Factory-direct supply Worldwide delivery & export documentation 12-month warranty · extended options
  • Core of premium cold-rolled grain-oriented silicon steel, stacked with multi-step 45° fully mitred joints
  • Low no-load and load losses in service
  • Cylindrical winding structure with balanced ampere-turns — strong short-circuit withstand
  • Elastic corrugated tank or panel radiators absorb oil volume change from heating and cooling
  • Tank surface de-rusted, de-greased and phosphated before primer and topcoat — fit for metallurgy, petrochemica
  • Maintenance-free: no insulating-oil replacement
Overview

A cleaner, more reliable approach to MV switching

The HP-ELS series replaces SF₆ with environmentally friendly insulating media while keeping the proven safety and performance utilities expect from gas-insulated switchgear.

Product Overview

The S□-M series oil-immersed power transformer uses mineral oil as its insulation system; its oil-tank processing meets special outdoor requirements for metallurgical and petrochemical systems and for humid, polluted areas. It complies with the GB/T 1094 series, GB/T 25446-2010 and GB 20052-2024.

Specifications

Technical specifications

Headline ratings at a glance, followed by the full technical data sheet. Exact values are confirmed per project configuration.

HV / LV voltage10·10.5 kV / 0.4 kV
Tap range / vector group±2×2.5 %·±5 % / Dyn11·Yyn0
Short-circuit impedance4.0 / 4.5 / 5.0%
ParameterValue
HV / LV voltage10·10.5 kV / 0.4 kV
Tap range / vector group±2×2.5 %·±5 % / Dyn11·Yyn0
Short-circuit impedance4.0 / 4.5 / 5.0 %
30 kVA — no-load / load70·65 / 505·455
100 kVA — no-load / load135·120 / 1265·1140
315 kVA — no-load / load305·270 / 3065·2760
630 kVA — no-load / load510·460 / 4960·4460
1250 kVA — no-load / load870·780 / 9600·8640
2500 kVA — no-load / load1440·1280 / 16960·15270
NoteDyn11 / Yyn0 by rating · full range 30–2500 kVA
Model Meaning

Reading the model designation

S Three-phase
Loss level code
M Sealed type
Rated capacity kVA
System nominal voltage kV

Generated automatically from each product's model code.

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