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S11 Series Oil-Immersed Transformers

162 Models available

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S11 Oil-Immersed Transformers

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S11 Series - Oil-Immersed Distribution Transformers (Level 11 Efficiency)

The S11 series represents standard oil-immersed distribution transformers meeting Level 11 energy efficiency standards, widely used in power distribution networks. Rated 10–5000 kVA, 0.48–35 kV primary and 0.208–0.48 kV secondary, mineral-oil insulation with 65 K temperature rise. Suitable for utility distribution networks, substations, solar farms, and industrial power systems.

Model Number Breakdown

11Performance level designation, corresponds to Level 11 energy efficiency standard
SThree-phase power transformer
162+
Available Models
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Engineering Calculators

Key Features

  • Level 11 energy efficiency rating
  • Reliable oil-immersion insulation
  • Proven technology with long service life
  • Suitable for outdoor installation

Applications

  • Power distribution networks
  • Industrial power supply
  • Rural electrification
  • General utility applications

TECHNICAL DRAWING

Model: S11-R-M-250/10/0.48 | Type: Oil-immersed transformer | Capacity: 250 kVA

FRONT ELEVATION

Oil level1U1V1W2U2V2W2NTAPN.P.180mm240mm

ELECTRICAL SCHEMATIC

HV WINDING (Delta)1U1V1WLV WINDING (Star)2U2V2W2NDelta-Wye (IEEE Std)

EFFICIENCY vs LOAD

90%95%98%99%0%25%50%75%100%≈99%load %efficiency %

SIDE VIEW

Oil level135mm

TOP VIEW

1U1V1W2U2V2W2N135mm

TERMINAL BLOCK

HV TERMINAL BLOCK1U1V1W1N1PELV TERMINAL BLOCK2U2V2W2N2PE2122Terminal block configurationTin-plated copper busbar

CORE & WINDING

OIL / TANKHV winding/bushingINSULATIONLV winding/bushingIron coreconcentric cross-section
LEGEND:
Iron core
HV winding/bushing
LV winding/bushing
Dimension line

Specifications Range

All specifications and dimensions can be customized upon request

Model Selector

Key parametersModel Range
Capacity10–5000 kVA
HV Voltage (kV)10, 6, 35, 0.48
LV Voltage (kV)0.4, 0.48, 0.22, 0.208
Frequency (Hz)50, 60
Impedance (%)4, 4.5, 6, 7
CoolingONAN
EfficiencyClass 1
StandardIEC 60076, IEEE C57 / ANSI C84.1
ConnectionDyn11 (IEC), Delta-Wye (IEEE Std)
Insulation classA (105°C)
Allowed temperature rise65
Noise level≤33 dB(A), ≤34 dB(A), ≤35 dB(A), ≤36 dB(A), ≤37 dB(A), ≤38 dB(A)…
Tap Changer±2×2.5% Multi-tap, ±5% Single-tap, ±5×2.5% Multi-tap, ±8×1.25% OLTC
No-load loss57–3892 W
Load loss330–38786 W
Select 2-3 models to compare
CompareModelCapacity (kVA)HV Voltage (kV)LV Voltage (kV)WeightDimensions
S11-R-M-10/10/0.410kVA100.4229 kg650×362×577 mm
S11-R-M-10/6/0.410kVA60.4229 kg650×362×577 mm
S11-R-M-10/35/0.410kVA350.4229 kg650×362×577 mm
S11-R-M-10/10/0.4810kVA100.48229 kg650×362×577 mm
S11-R-M-10/10/0.2210kVA100.22229 kg650×362×577 mm
S11-R-M-10/0.48/0.20810kVA0.480.208229 kg650×362×577 mm
S11-R-M-15/10/0.415kVA100.4247 kg675×382×596 mm
S11-R-M-15/6/0.415kVA60.4247 kg675×382×596 mm
S11-R-M-15/35/0.415kVA350.4247 kg675×382×596 mm
S11-R-M-15/10/0.4815kVA100.48247 kg675×382×596 mm
S11-R-M-15/10/0.2215kVA100.22247 kg675×382×596 mm
S11-R-M-15/0.48/0.20815kVA0.480.208247 kg675×382×596 mm
S11-R-M-20/10/0.420kVA100.4265 kg700×402×615 mm
S11-R-M-20/6/0.420kVA60.4265 kg700×402×615 mm
S11-R-M-20/35/0.420kVA350.4265 kg700×402×615 mm
S11-R-M-20/10/0.4820kVA100.48265 kg700×402×615 mm
S11-R-M-20/10/0.2220kVA100.22265 kg700×402×615 mm
S11-R-M-20/0.48/0.20820kVA0.480.208265 kg700×402×615 mm
S11-R-M-25/10/0.425kVA100.4288 kg784×443×634 mm
S11-R-M-25/6/0.425kVA60.4288 kg784×443×634 mm
S11-R-M-25/35/0.425kVA350.4288 kg784×443×634 mm
S11-R-M-25/10/0.4825kVA100.48288 kg784×443×634 mm
S11-R-M-25/10/0.2225kVA100.22288 kg784×443×634 mm
S11-R-M-25/0.48/0.20825kVA0.480.208288 kg784×443×634 mm
S11-R-M-30/10/0.430kVA100.4311 kg869×483×654 mm
S11-R-M-30/6/0.430kVA60.4311 kg869×483×654 mm
S11-R-M-30/35/0.430kVA350.4311 kg869×483×654 mm
S11-R-M-30/10/0.4830kVA100.48311 kg869×483×654 mm
S11-R-M-30/10/0.2230kVA100.22311 kg869×483×654 mm
S11-R-M-30/0.48/0.20830kVA0.480.208311 kg869×483×654 mm
S11-R-M-40/10/0.440kVA100.4370 kg884×491×673 mm
S11-R-M-40/6/0.440kVA60.4370 kg884×491×673 mm
S11-R-M-40/35/0.440kVA350.4370 kg884×491×673 mm
S11-R-M-40/10/0.4840kVA100.48370 kg884×491×673 mm
S11-R-M-40/10/0.2240kVA100.22370 kg884×491×673 mm
S11-R-M-40/0.48/0.20840kVA0.480.208370 kg884×491×673 mm
S11-R-M-50/10/0.450kVA100.4430 kg899×499×692 mm
S11-R-M-50/6/0.450kVA60.4430 kg899×499×692 mm
S11-R-M-50/35/0.450kVA350.4430 kg899×499×692 mm
S11-R-M-50/10/0.4850kVA100.48430 kg899×499×692 mm
S11-R-M-50/10/0.2250kVA100.22430 kg899×499×692 mm
S11-R-M-50/0.48/0.20850kVA0.480.208430 kg899×499×692 mm
S11-R-M-63/10/0.463kVA100.4480 kg944×519×727 mm
S11-R-M-63/6/0.463kVA60.4480 kg944×519×727 mm
S11-R-M-63/35/0.463kVA350.4480 kg944×519×727 mm
S11-R-M-63/10/0.4863kVA100.48480 kg944×519×727 mm
S11-R-M-63/10/0.2263kVA100.22480 kg944×519×727 mm
S11-R-M-63/0.48/0.20863kVA0.480.208480 kg944×519×727 mm
S11-R-M-80/10/0.480kVA100.4549 kg999×547×769 mm
S11-R-M-80/6/0.480kVA60.4549 kg999×547×769 mm
S11-R-M-80/35/0.480kVA350.4549 kg999×547×769 mm
S11-R-M-80/10/0.4880kVA100.48549 kg999×547×769 mm
S11-R-M-80/10/0.2280kVA100.22549 kg999×547×769 mm
S11-R-M-80/0.48/0.20880kVA0.480.208549 kg999×547×769 mm
S11-R-M-100/10/0.4100kVA100.4597 kg990×670×930 mm
S11-R-M-100/6/0.4100kVA60.4597 kg990×670×930 mm
S11-R-M-100/35/0.4100kVA350.4597 kg990×670×930 mm
S11-R-M-100/10/0.48100kVA100.48597 kg990×670×930 mm
S11-R-M-100/10/0.22100kVA100.22597 kg990×670×930 mm
S11-R-M-100/0.48/0.208100kVA0.480.208597 kg990×670×930 mm
S11-R-M-125/10/0.4125kVA100.4668 kg1079×579×846 mm
S11-R-M-125/6/0.4125kVA60.4668 kg1079×579×846 mm
S11-R-M-125/35/0.4125kVA350.4668 kg1079×579×846 mm
S11-R-M-125/10/0.48125kVA100.48668 kg1079×579×846 mm
S11-R-M-125/10/0.22125kVA100.22668 kg1079×579×846 mm
S11-R-M-125/0.48/0.208125kVA0.480.208668 kg1079×579×846 mm
S11-R-M-160/10/0.4160kVA100.4764 kg1045×685×965 mm
S11-R-M-160/6/0.4160kVA60.4764 kg1045×685×965 mm
S11-R-M-160/35/0.4160kVA350.4764 kg1045×685×965 mm
S11-R-M-160/10/0.48160kVA100.48764 kg1045×685×965 mm
S11-R-M-160/10/0.22160kVA100.22764 kg1045×685×965 mm
S11-R-M-160/0.48/0.208160kVA0.480.208764 kg1045×685×965 mm
S11-R-M-200/10/0.4200kVA100.4842 kg1120×750×1000 mm
S11-R-M-200/6/0.4200kVA60.4842 kg1120×750×1000 mm
S11-R-M-200/35/0.4200kVA350.4842 kg1120×750×1000 mm
S11-R-M-200/10/0.48200kVA100.48842 kg1120×750×1000 mm
S11-R-M-200/10/0.22200kVA100.22842 kg1120×750×1000 mm
S11-R-M-200/0.48/0.208200kVA0.480.208842 kg1120×750×1000 mm
S11-R-M-250/10/0.4250kVA100.4960 kg1189×829×1000 mm
S11-R-M-250/6/0.4250kVA60.4960 kg1189×829×1000 mm
S11-R-M-250/35/0.4250kVA350.4960 kg1189×829×1000 mm
S11-R-M-250/10/0.48250kVA100.48960 kg1189×829×1000 mm
S11-R-M-250/10/0.22250kVA100.22960 kg1189×829×1000 mm
S11-R-M-250/0.48/0.208250kVA0.480.208960 kg1189×829×1000 mm
S11-R-M-315/10/0.4315kVA100.41150 kg1350×930×1040 mm
S11-R-M-315/6/0.4315kVA60.41150 kg1350×930×1040 mm
S11-R-M-315/35/0.4315kVA350.41150 kg1350×930×1040 mm
S11-R-M-315/10/0.48315kVA100.481150 kg1350×930×1040 mm
S11-R-M-315/10/0.22315kVA100.221150 kg1350×930×1040 mm
S11-R-M-315/0.48/0.208315kVA0.480.2081150 kg1350×930×1040 mm
S11-R-M-400/10/0.4400kVA100.41349 kg1300×860×1090 mm
S11-R-M-400/6/0.4400kVA60.41349 kg1300×860×1090 mm
S11-R-M-400/35/0.4400kVA350.41349 kg1300×860×1090 mm
S11-R-M-400/10/0.48400kVA100.481349 kg1300×860×1090 mm
S11-R-M-400/10/0.22400kVA100.221349 kg1300×860×1090 mm
S11-R-M-400/0.48/0.208400kVA0.480.2081349 kg1300×860×1090 mm
S11-R-M-500/10/0.4500kVA100.41504 kg1390×960×1120 mm
S11-R-M-500/6/0.4500kVA60.41504 kg1390×960×1120 mm
S11-R-M-500/35/0.4500kVA350.41504 kg1390×960×1120 mm
S11-R-M-500/10/0.48500kVA100.481504 kg1390×960×1120 mm
S11-R-M-500/10/0.22500kVA100.221504 kg1390×960×1120 mm
S11-R-M-500/0.48/0.208500kVA0.480.2081504 kg1390×960×1120 mm
S11-R-M-630/10/0.4630kVA100.41818 kg1465×1020×1160 mm
S11-R-M-630/6/0.4630kVA60.41818 kg1465×1020×1160 mm
S11-R-M-630/35/0.4630kVA350.41818 kg1465×1020×1160 mm
S11-R-M-630/10/0.48630kVA100.481818 kg1465×1020×1160 mm
S11-R-M-630/10/0.22630kVA100.221818 kg1465×1020×1160 mm
S11-R-M-630/0.48/0.208630kVA0.480.2081818 kg1465×1020×1160 mm
S11-R-M-800/10/0.4800kVA100.42136 kg1525×1060×1200 mm
S11-R-M-800/6/0.4800kVA60.42136 kg1525×1060×1200 mm
S11-R-M-800/35/0.4800kVA350.42136 kg1525×1060×1200 mm
S11-R-M-800/10/0.48800kVA100.482136 kg1525×1060×1200 mm
S11-R-M-800/10/0.22800kVA100.222136 kg1525×1060×1200 mm
S11-R-M-800/0.48/0.208800kVA0.480.2082136 kg1525×1060×1200 mm
S11-R-M-1000/10/0.41000kVA100.42522 kg1750×1270×1230 mm
S11-R-M-1000/6/0.41000kVA60.42522 kg1750×1270×1230 mm
S11-R-M-1000/35/0.41000kVA350.42522 kg1750×1270×1230 mm
S11-R-M-1000/10/0.481000kVA100.482522 kg1750×1270×1230 mm
S11-R-M-1000/10/0.221000kVA100.222522 kg1750×1270×1230 mm
S11-R-M-1000/0.48/0.2081000kVA0.480.2082522 kg1750×1270×1230 mm
S11-R-M-1250/10/0.41250kVA100.42943 kg1720×1240×1300 mm
S11-R-M-1250/6/0.41250kVA60.42943 kg1720×1240×1300 mm
S11-R-M-1250/35/0.41250kVA350.42943 kg1720×1240×1300 mm
S11-R-M-1250/10/0.481250kVA100.482943 kg1720×1240×1300 mm
S11-R-M-1250/10/0.221250kVA100.222943 kg1720×1240×1300 mm
S11-R-M-1250/0.48/0.2081250kVA0.480.2082943 kg1720×1240×1300 mm
S11-R-M-1600/10/0.41600kVA100.44069.5 kg1879×1312×1492 mm
S11-R-M-1600/6/0.41600kVA60.44069.5 kg1879×1312×1492 mm
S11-R-M-1600/35/0.41600kVA350.44069.5 kg1879×1312×1492 mm
S11-R-M-1600/10/0.481600kVA100.484069.5 kg1879×1312×1492 mm
S11-R-M-1600/10/0.221600kVA100.224069.5 kg1879×1312×1492 mm
S11-R-M-1600/0.48/0.2081600kVA0.480.2084069.5 kg1879×1312×1492 mm
S11-R-M-2000/10/0.42000kVA100.44572.5 kg1999×1368×1538 mm
S11-R-M-2000/6/0.42000kVA60.44572.5 kg1999×1368×1538 mm
S11-R-M-2000/35/0.42000kVA350.44572.5 kg1999×1368×1538 mm
S11-R-M-2000/10/0.482000kVA100.484572.5 kg1999×1368×1538 mm
S11-R-M-2000/10/0.222000kVA100.224572.5 kg1999×1368×1538 mm
S11-R-M-2000/0.48/0.2082000kVA0.480.2084572.5 kg1999×1368×1538 mm
S11-R-M-2500/10/0.42500kVA100.45304 kg2179×1062×1515 mm
S11-R-M-2500/6/0.42500kVA60.45304 kg2179×1062×1515 mm
S11-R-M-2500/35/0.42500kVA350.45304 kg2179×1062×1515 mm
S11-R-M-2500/10/0.482500kVA100.485304 kg2179×1062×1515 mm
S11-R-M-2500/10/0.222500kVA100.225304 kg2179×1062×1515 mm
S11-R-M-2500/0.48/0.2082500kVA0.480.2085304 kg2179×1062×1515 mm
S11-R-M-3150/10/0.43150kVA100.46310 kg2299×1167×1615 mm
S11-R-M-3150/6/0.43150kVA60.46310 kg2299×1167×1615 mm
S11-R-M-3150/35/0.43150kVA350.46310 kg2299×1167×1615 mm
S11-R-M-3150/10/0.483150kVA100.486310 kg2299×1167×1615 mm
S11-R-M-3150/10/0.223150kVA100.226310 kg2299×1167×1615 mm
S11-R-M-3150/0.48/0.2083150kVA0.480.2086310 kg2299×1167×1615 mm
S11-R-M-4000/10/0.44000kVA100.47590 kg2498×1247×1730 mm
S11-R-M-4000/6/0.44000kVA60.47590 kg2498×1247×1730 mm
S11-R-M-4000/35/0.44000kVA350.47590 kg2498×1247×1730 mm
S11-R-M-4000/10/0.484000kVA100.487590 kg2498×1247×1730 mm
S11-R-M-4000/10/0.224000kVA100.227590 kg2498×1247×1730 mm
S11-R-M-4000/0.48/0.2084000kVA0.480.2087590 kg2498×1247×1730 mm
S11-R-M-5000/10/0.45000kVA100.49145 kg2698×1328×1845 mm
S11-R-M-5000/6/0.45000kVA60.49145 kg2698×1328×1845 mm
S11-R-M-5000/35/0.45000kVA350.49145 kg2698×1328×1845 mm
S11-R-M-5000/10/0.485000kVA100.489145 kg2698×1328×1845 mm
S11-R-M-5000/10/0.225000kVA100.229145 kg2698×1328×1845 mm
S11-R-M-5000/0.48/0.2085000kVA0.480.2089145 kg2698×1328×1845 mm

Selection Guide

1

Capacity

Sum the connected load and add a 20-30% margin for future growth and starting surges.

2

Voltage

Match the HV side to your supply (10/20 kV) and the LV side to your load (typically 400 V).

3

Cooling

ONAN is standard up to mid-range capacity; choose ONAF for larger units needing higher output.

- Frequently Asked Questions

What is the difference between oil-immersed and dry-type?

Oil-immersed offers higher capacity and better overload at lower cost per kVA, but requires outdoor or ventilated installation.

What cooling does S11 use?

ONAN (oil natural, air natural) standard, with ONAF available for larger units.

What maintenance does S11 need?

Periodic oil testing every 3-5 years for hermetic units; open units may need occasional top-up.

Instant Selection & Quote Calculator

Select your specifications to get an estimated price instantly.

1 · Configure
2 · Your price
EXW (FOB Qingdao)
$2,332
Range $2,146 ~ $2,519 (±8%)
Price Breakdown
Base price (interpolation)$2,332
× Product factor×1.0000
× Country factor×1.0000
× Copper-linked factor×1.0000
+ Options / accessories$0
Shipping quoted separately per destination port.

Aluminum winding — no copper linkage

Reference prices are for estimation only and do not constitute a formal offer.

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