China pad mounted transformer manufactured by Rockwill Electric. These series of pad-mounted transformer is oil-immersed with power rating from 25 to 2500kVA at 50/60 Hz power transmission and distribution system.
33kV 2500kVA pad mounted transformer
General
Oil immersed pad-mounted transformer is suitable for 3.6kV up to 40.5kV power class.These series of pad-mounted transformer is oil-immersed with power rating from 25 to 2500kVA at 50/60 Hz power transmission and distribution system for power supply and lighting inindustrial and agricultural field.These pad-mounted transformer are produced with nominal Voltage in primary winding 6 up to 36 kV. Nominal Voltage in secondary winding is 0.22 up to 0.66kV.Scheme and connection group of windings is optional: Dyn0,Dyn5,Dyn11,Yyn0 etc.according to customer demand it is possible to make transformers with different connection ofthe Voltage s and other construction solution.
Service environment
a) Air temperature: Maximum temperature: +40℃; Minimum temperature:-35℃
b) Humidity: Monthly average humidity 95%; Daily average humidity 90% .
c) Altitude above sea level: Maximum installation altitude: 2500m
d) Ambient air not apparently polluted by corrosive and flammable gas, vapor etc.
e) No frequent violent shake
Pad mounted transformer structure is divided into front and rear parts.The front parts is LV andHV cabin including high and low voltage terminals, load switch, no-load tap-changer, plug-in fuse,pressure relief valve, oil temperature gauge, oil level gauge.The rear parts is oil tank including transformer oil,iron core ,winding and current-limiting backup fuse.
Each different outside coating style for client options
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| A type steel sheet | B type steel sheet | H type steel sheet | S type AL alloy |
Protection
The pad mounted transformer is protected from the combination of current-limiting backup protection fuse and Plug - in fuse . The protection principle is advanced, economical and easy to operate.Plug-in fuse is the brief element of oil-transformer,to protect the equipment when over-current.When install the fuse wire in it,the plug-in fuse will provide the safe,highly efficient protection,according to the current, oil-temperature. The Backup Current limiting fuse highly efficient current-limiting section minimizes the effects of high fault current stresses on equipment and the distribution system.Its minimum interrupting rating is coordinated with that of a low current interrupter to avoid undesirable low current operation;yet its maximum interrupting rating will clear the highest fault currents likely to occur. Higher continuous current ratings can be achievedby connecting two fuses in parallel.
Connector
Load break Elbow connector is a fully-shielded andinsulated plug-in termination for connectingunderground cable to distributionpower system of pad mounted transformer,surrounding power supply branch box,cablebranch box equipped with loadbreak connections.It can meet the demand of lines in nuclear.The loadbreak Elbows are molded using highquality sulfur-cured insulating and semi-conductingEPDM rubber.Standard features include acoppertop connector,tin-plated copperloadbreak probe with an ablative arc-follower tipand stainless steel reinforced pulling-eye.Anoptional capacitive test point.made ofcorrosion resistance plastic,is available for usewith fault indicators.
Load break switch
The Load break switch is three phase gang-operated type,with spring mechanism,andit is able to switch on/off under on load condition.And there is 2 different types Load break switch:2-position& 4-position.2-position is used for radial feeder design distribution system,and 4-position is usedfor loop feeder design distribution system.
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| 2-Position Load break switch | 4-Position Load break switch |
Electrical schematic diagram:
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| Loop feeder design |
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| Radial feederdesign |
| Name | Unit | HV side | Transformer | LV side |
| Rated voltage | kV | 3.6~40.5 | / | 0.4~0.69 |
| Rated current | A | 0.5 | / | 4000A |
| Frequency | Hz | 50/60 | ||
| Rated Capacity | kVA | 25~2500kVA | ||
| Pfr withstand | kV | 35 | 5 | |
| BIL | kV | 95 | ||
| Noisy Grade | dB | Oil type less than 45dB | ||
| Appearance Dimensions | mm | According to primacy wiring circuit schema | ||
Technical Service:
ROCKWILL®, China. Provide with best support
Tel: 0086-577-27869969
Email: barry@rockwill.cn
