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SZ Series Oil-Immersed Transformers

162 Models available

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SZ Oil-Immersed Transformers

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SZ Series - On-Load Tap Changer Oil-Immersed Transformers

The SZ series oil-immersed transformers integrate an on-load tap changer (OLTC) for automatic voltage regulation under load, available across 6kV, 10kV and 35kV primary voltages per IEC 60076. 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

SThree-phase power transformer
ZOn-load tap changer (OLTC)
162+
Available Models
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Key Features

  • On-load tap changer for voltage regulation under load
  • 6 / 10 / 35 kV primary voltage options
  • IEC 60076 compliant
  • Reliable oil-immersion insulation

Applications

  • Distribution networks with fluctuating loads
  • Voltage-sensitive industrial plants
  • Utility grid voltage regulation

TECHNICAL DRAWING

Model: SZ11-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
SZ11-M-10/10/0.410kVA100.4229 kg650×362×577 mm
SZ11-M-10/6/0.410kVA60.4229 kg650×362×577 mm
SZ11-M-10/35/0.410kVA350.4229 kg650×362×577 mm
SZ11-M-10/10/0.4810kVA100.48229 kg650×362×577 mm
SZ11-M-10/10/0.2210kVA100.22229 kg650×362×577 mm
SZ11-M-10/0.48/0.20810kVA0.480.208229 kg650×362×577 mm
SZ11-M-15/10/0.415kVA100.4247 kg675×382×596 mm
SZ11-M-15/6/0.415kVA60.4247 kg675×382×596 mm
SZ11-M-15/35/0.415kVA350.4247 kg675×382×596 mm
SZ11-M-15/10/0.4815kVA100.48247 kg675×382×596 mm
SZ11-M-15/10/0.2215kVA100.22247 kg675×382×596 mm
SZ11-M-15/0.48/0.20815kVA0.480.208247 kg675×382×596 mm
SZ11-M-20/10/0.420kVA100.4265 kg700×402×615 mm
SZ11-M-20/6/0.420kVA60.4265 kg700×402×615 mm
SZ11-M-20/35/0.420kVA350.4265 kg700×402×615 mm
SZ11-M-20/10/0.4820kVA100.48265 kg700×402×615 mm
SZ11-M-20/10/0.2220kVA100.22265 kg700×402×615 mm
SZ11-M-20/0.48/0.20820kVA0.480.208265 kg700×402×615 mm
SZ11-M-25/10/0.425kVA100.4288 kg784×443×634 mm
SZ11-M-25/6/0.425kVA60.4288 kg784×443×634 mm
SZ11-M-25/35/0.425kVA350.4288 kg784×443×634 mm
SZ11-M-25/10/0.4825kVA100.48288 kg784×443×634 mm
SZ11-M-25/10/0.2225kVA100.22288 kg784×443×634 mm
SZ11-M-25/0.48/0.20825kVA0.480.208288 kg784×443×634 mm
SZ11-M-30/10/0.430kVA100.4311 kg869×483×654 mm
SZ11-M-30/6/0.430kVA60.4311 kg869×483×654 mm
SZ11-M-30/35/0.430kVA350.4311 kg869×483×654 mm
SZ11-M-30/10/0.4830kVA100.48311 kg869×483×654 mm
SZ11-M-30/10/0.2230kVA100.22311 kg869×483×654 mm
SZ11-M-30/0.48/0.20830kVA0.480.208311 kg869×483×654 mm
SZ11-M-40/10/0.440kVA100.4370 kg884×491×673 mm
SZ11-M-40/6/0.440kVA60.4370 kg884×491×673 mm
SZ11-M-40/35/0.440kVA350.4370 kg884×491×673 mm
SZ11-M-40/10/0.4840kVA100.48370 kg884×491×673 mm
SZ11-M-40/10/0.2240kVA100.22370 kg884×491×673 mm
SZ11-M-40/0.48/0.20840kVA0.480.208370 kg884×491×673 mm
SZ11-M-50/10/0.450kVA100.4430 kg899×499×692 mm
SZ11-M-50/6/0.450kVA60.4430 kg899×499×692 mm
SZ11-M-50/35/0.450kVA350.4430 kg899×499×692 mm
SZ11-M-50/10/0.4850kVA100.48430 kg899×499×692 mm
SZ11-M-50/10/0.2250kVA100.22430 kg899×499×692 mm
SZ11-M-50/0.48/0.20850kVA0.480.208430 kg899×499×692 mm
SZ11-M-63/10/0.463kVA100.4480 kg944×519×727 mm
SZ11-M-63/6/0.463kVA60.4480 kg944×519×727 mm
SZ11-M-63/35/0.463kVA350.4480 kg944×519×727 mm
SZ11-M-63/10/0.4863kVA100.48480 kg944×519×727 mm
SZ11-M-63/10/0.2263kVA100.22480 kg944×519×727 mm
SZ11-M-63/0.48/0.20863kVA0.480.208480 kg944×519×727 mm
SZ11-M-80/10/0.480kVA100.4549 kg999×547×769 mm
SZ11-M-80/6/0.480kVA60.4549 kg999×547×769 mm
SZ11-M-80/35/0.480kVA350.4549 kg999×547×769 mm
SZ11-M-80/10/0.4880kVA100.48549 kg999×547×769 mm
SZ11-M-80/10/0.2280kVA100.22549 kg999×547×769 mm
SZ11-M-80/0.48/0.20880kVA0.480.208549 kg999×547×769 mm
SZ11-M-100/10/0.4100kVA100.4597 kg990×670×930 mm
SZ11-M-100/6/0.4100kVA60.4597 kg990×670×930 mm
SZ11-M-100/35/0.4100kVA350.4597 kg990×670×930 mm
SZ11-M-100/10/0.48100kVA100.48597 kg990×670×930 mm
SZ11-M-100/10/0.22100kVA100.22597 kg990×670×930 mm
SZ11-M-100/0.48/0.208100kVA0.480.208597 kg990×670×930 mm
SZ11-M-125/10/0.4125kVA100.4668 kg1079×579×846 mm
SZ11-M-125/6/0.4125kVA60.4668 kg1079×579×846 mm
SZ11-M-125/35/0.4125kVA350.4668 kg1079×579×846 mm
SZ11-M-125/10/0.48125kVA100.48668 kg1079×579×846 mm
SZ11-M-125/10/0.22125kVA100.22668 kg1079×579×846 mm
SZ11-M-125/0.48/0.208125kVA0.480.208668 kg1079×579×846 mm
SZ11-M-160/10/0.4160kVA100.4764 kg1045×685×965 mm
SZ11-M-160/6/0.4160kVA60.4764 kg1045×685×965 mm
SZ11-M-160/35/0.4160kVA350.4764 kg1045×685×965 mm
SZ11-M-160/10/0.48160kVA100.48764 kg1045×685×965 mm
SZ11-M-160/10/0.22160kVA100.22764 kg1045×685×965 mm
SZ11-M-160/0.48/0.208160kVA0.480.208764 kg1045×685×965 mm
SZ11-M-200/10/0.4200kVA100.4842 kg1120×750×1000 mm
SZ11-M-200/6/0.4200kVA60.4842 kg1120×750×1000 mm
SZ11-M-200/35/0.4200kVA350.4842 kg1120×750×1000 mm
SZ11-M-200/10/0.48200kVA100.48842 kg1120×750×1000 mm
SZ11-M-200/10/0.22200kVA100.22842 kg1120×750×1000 mm
SZ11-M-200/0.48/0.208200kVA0.480.208842 kg1120×750×1000 mm
SZ11-M-250/10/0.4250kVA100.4960 kg1189×829×1000 mm
SZ11-M-250/6/0.4250kVA60.4960 kg1189×829×1000 mm
SZ11-M-250/35/0.4250kVA350.4960 kg1189×829×1000 mm
SZ11-M-250/10/0.48250kVA100.48960 kg1189×829×1000 mm
SZ11-M-250/10/0.22250kVA100.22960 kg1189×829×1000 mm
SZ11-M-250/0.48/0.208250kVA0.480.208960 kg1189×829×1000 mm
SZ11-M-315/10/0.4315kVA100.41150 kg1350×930×1040 mm
SZ11-M-315/6/0.4315kVA60.41150 kg1350×930×1040 mm
SZ11-M-315/35/0.4315kVA350.41150 kg1350×930×1040 mm
SZ11-M-315/10/0.48315kVA100.481150 kg1350×930×1040 mm
SZ11-M-315/10/0.22315kVA100.221150 kg1350×930×1040 mm
SZ11-M-315/0.48/0.208315kVA0.480.2081150 kg1350×930×1040 mm
SZ11-M-400/10/0.4400kVA100.41349 kg1300×860×1090 mm
SZ11-M-400/6/0.4400kVA60.41349 kg1300×860×1090 mm
SZ11-M-400/35/0.4400kVA350.41349 kg1300×860×1090 mm
SZ11-M-400/10/0.48400kVA100.481349 kg1300×860×1090 mm
SZ11-M-400/10/0.22400kVA100.221349 kg1300×860×1090 mm
SZ11-M-400/0.48/0.208400kVA0.480.2081349 kg1300×860×1090 mm
SZ11-M-500/10/0.4500kVA100.41504 kg1390×960×1120 mm
SZ11-M-500/6/0.4500kVA60.41504 kg1390×960×1120 mm
SZ11-M-500/35/0.4500kVA350.41504 kg1390×960×1120 mm
SZ11-M-500/10/0.48500kVA100.481504 kg1390×960×1120 mm
SZ11-M-500/10/0.22500kVA100.221504 kg1390×960×1120 mm
SZ11-M-500/0.48/0.208500kVA0.480.2081504 kg1390×960×1120 mm
SZ11-M-630/10/0.4630kVA100.41818 kg1465×1020×1160 mm
SZ11-M-630/6/0.4630kVA60.41818 kg1465×1020×1160 mm
SZ11-M-630/35/0.4630kVA350.41818 kg1465×1020×1160 mm
SZ11-M-630/10/0.48630kVA100.481818 kg1465×1020×1160 mm
SZ11-M-630/10/0.22630kVA100.221818 kg1465×1020×1160 mm
SZ11-M-630/0.48/0.208630kVA0.480.2081818 kg1465×1020×1160 mm
SZ11-M-800/10/0.4800kVA100.42136 kg1525×1060×1200 mm
SZ11-M-800/6/0.4800kVA60.42136 kg1525×1060×1200 mm
SZ11-M-800/35/0.4800kVA350.42136 kg1525×1060×1200 mm
SZ11-M-800/10/0.48800kVA100.482136 kg1525×1060×1200 mm
SZ11-M-800/10/0.22800kVA100.222136 kg1525×1060×1200 mm
SZ11-M-800/0.48/0.208800kVA0.480.2082136 kg1525×1060×1200 mm
SZ11-M-1000/10/0.41000kVA100.42522 kg1750×1270×1230 mm
SZ11-M-1000/6/0.41000kVA60.42522 kg1750×1270×1230 mm
SZ11-M-1000/35/0.41000kVA350.42522 kg1750×1270×1230 mm
SZ11-M-1000/10/0.481000kVA100.482522 kg1750×1270×1230 mm
SZ11-M-1000/10/0.221000kVA100.222522 kg1750×1270×1230 mm
SZ11-M-1000/0.48/0.2081000kVA0.480.2082522 kg1750×1270×1230 mm
SZ11-M-1250/10/0.41250kVA100.42943 kg1720×1240×1300 mm
SZ11-M-1250/6/0.41250kVA60.42943 kg1720×1240×1300 mm
SZ11-M-1250/35/0.41250kVA350.42943 kg1720×1240×1300 mm
SZ11-M-1250/10/0.481250kVA100.482943 kg1720×1240×1300 mm
SZ11-M-1250/10/0.221250kVA100.222943 kg1720×1240×1300 mm
SZ11-M-1250/0.48/0.2081250kVA0.480.2082943 kg1720×1240×1300 mm
SZ11-M-1600/10/0.41600kVA100.44069.5 kg1879×1312×1492 mm
SZ11-M-1600/6/0.41600kVA60.44069.5 kg1879×1312×1492 mm
SZ11-M-1600/35/0.41600kVA350.44069.5 kg1879×1312×1492 mm
SZ11-M-1600/10/0.481600kVA100.484069.5 kg1879×1312×1492 mm
SZ11-M-1600/10/0.221600kVA100.224069.5 kg1879×1312×1492 mm
SZ11-M-1600/0.48/0.2081600kVA0.480.2084069.5 kg1879×1312×1492 mm
SZ11-M-2000/10/0.42000kVA100.44572.5 kg1999×1368×1538 mm
SZ11-M-2000/6/0.42000kVA60.44572.5 kg1999×1368×1538 mm
SZ11-M-2000/35/0.42000kVA350.44572.5 kg1999×1368×1538 mm
SZ11-M-2000/10/0.482000kVA100.484572.5 kg1999×1368×1538 mm
SZ11-M-2000/10/0.222000kVA100.224572.5 kg1999×1368×1538 mm
SZ11-M-2000/0.48/0.2082000kVA0.480.2084572.5 kg1999×1368×1538 mm
SZ11-M-2500/10/0.42500kVA100.45304 kg2179×1062×1515 mm
SZ11-M-2500/6/0.42500kVA60.45304 kg2179×1062×1515 mm
SZ11-M-2500/35/0.42500kVA350.45304 kg2179×1062×1515 mm
SZ11-M-2500/10/0.482500kVA100.485304 kg2179×1062×1515 mm
SZ11-M-2500/10/0.222500kVA100.225304 kg2179×1062×1515 mm
SZ11-M-2500/0.48/0.2082500kVA0.480.2085304 kg2179×1062×1515 mm
SZ11-M-3150/10/0.43150kVA100.46310 kg2299×1167×1615 mm
SZ11-M-3150/6/0.43150kVA60.46310 kg2299×1167×1615 mm
SZ11-M-3150/35/0.43150kVA350.46310 kg2299×1167×1615 mm
SZ11-M-3150/10/0.483150kVA100.486310 kg2299×1167×1615 mm
SZ11-M-3150/10/0.223150kVA100.226310 kg2299×1167×1615 mm
SZ11-M-3150/0.48/0.2083150kVA0.480.2086310 kg2299×1167×1615 mm
SZ11-M-4000/10/0.44000kVA100.47590 kg2498×1247×1730 mm
SZ11-M-4000/6/0.44000kVA60.47590 kg2498×1247×1730 mm
SZ11-M-4000/35/0.44000kVA350.47590 kg2498×1247×1730 mm
SZ11-M-4000/10/0.484000kVA100.487590 kg2498×1247×1730 mm
SZ11-M-4000/10/0.224000kVA100.227590 kg2498×1247×1730 mm
SZ11-M-4000/0.48/0.2084000kVA0.480.2087590 kg2498×1247×1730 mm
SZ11-M-5000/10/0.45000kVA100.49145 kg2698×1328×1845 mm
SZ11-M-5000/6/0.45000kVA60.49145 kg2698×1328×1845 mm
SZ11-M-5000/35/0.45000kVA350.49145 kg2698×1328×1845 mm
SZ11-M-5000/10/0.485000kVA100.489145 kg2698×1328×1845 mm
SZ11-M-5000/10/0.225000kVA100.229145 kg2698×1328×1845 mm
SZ11-M-5000/0.48/0.2085000kVA0.480.2089145 kg2698×1328×1845 mm

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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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