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SZ20-3150/35 On-Load Regulating Power Transformer 3150 kVA 35kV

SZ20-3150/35 is a three-phase oil-immersed on-load regulating power transformer rated 3150 kVA, stepping 35 kV down to 10.5 kV with a Yd11 vector group. Its on-load tap changer offers nine positions at ±4×2.5% (38500 V to 31500 V) so output voltage can be corrected while the transformer stays energised. ONAN cooling, a sealed steel tank with TIG-welded seams, multi-fin radiators and a dual-pointer temperature display suit continuous outdoor duty in factory distribution, construction temporary power and rural grid renovation.

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  • SZ20-3150/35

  • SNTOOM

SZ20-3150/35 is a three-phase oil-immersed on-load regulating power transformer built for 35 kV distribution networks. It delivers 3150 kVA at a 35000 V / 10500 V ratio with a Yd11 vector group, and its on-load tap changer moves between nine positions while the unit stays energised, so the downstream voltage is corrected without a shutdown.

Key Features

  • On-load voltage regulation — nine tap positions from 38500 V to 31500 V in 875 V steps, changed under load with no interruption to supply.

  • ONAN oil-immersed cooling — oil-immersed coils and core with multi-fin radiators keep the temperature rise low and support stable full-load operation.

  • Sealed tank — steel welded tank with tight TIG seams, oil-resistant gasket and a bottom drain valve for long-term leak-free service and easy oil changes.

  • Ceramic HV insulators — dark brown ceramic bushings with a smooth surface for stable high-voltage insulation.

  • Dual-pointer temperature display — a black needle shows the current oil temperature and a red needle marks the set limit for quick visual monitoring.

  • Outdoor construction — rated for outdoor operating conditions, with a red handwheel drain valve that allows oil changes without disassembly.

Tap Position and Voltage

Tap Position

HV Voltage (V)

HV Current (A)

LV Voltage (V)

LV Current (A)

1

38500

-

-

-

2

37625

-

-

-

3

36750

-

-

-

4

35875

-

-

-

5 (rated)

35000

51.96

10500

173.2

6

34125

-

-

-

7

33250

-

-

-

8

32375

-

-

-

9

31500

-

-

-

Technical Parameters

Item

Value

Product Model

SZ20-3150/35

Rated Capacity

3150 kVA

Rated Voltage

35000 ± 4×2.5% / 10500 V

Rated Frequency

50 Hz

Phases

3

Vector Group

Yd11

No-Load Loss

2743 W

Load Loss

22321 W

Cooling Method

ONAN

Operating Condition

Outdoor

Impedance Voltage

6.80 %

Insulation Level

LI 200 AC 85 / LI 75 AC 35

Active Part Lifting Weight

3750 kg

Oil Weight

1650 kg

Total Weight

7590 kg

Applications

  • Factory power distribution

  • Residential power supply

  • Construction temporary power

  • Rural grid renovation

All ratings above are taken from the SZ20-3150/35 data sheet. For a different capacity, voltage ratio or vector group, send us the required rating and we will confirm the design and quotation.

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Electric Co., Ltd. was established in2009 , specializes in the production of various high-low-voltage equipment.

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Contact

 86-577-61721053.
     86-577-56848069.
     86-1336978582.
     86-15657768868.
   No.218,Liule Road,Liushi Town325604,Yueqing City,Wenzhou City,Zhejiang Province,China
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