MOTOR STARTING AUTOTRANSFORMER

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Motor starting autotransformers are a special transformers used in the autotransformer starting of a industrial motors. Autotransformer starting of motors is used widely in starting large industrial motors due to its advantage of providing the highest starting torque with lowest starting line current compared to other reduced voltage starting methods. The reduced voltage taps of the motor starting autotransformer are used to reduce the starting current of the transformer. Contactors switch between the taps, incrementally, increasing the votatge applied to motor as it gets up to speed, while ensuring the starting current is limited. Once the motor reached rated speed, the autotransformer is removed from the circuit entirely, avoiding any unnecessary energization losses..

Industry Standards:

  • CSA certified

  • UL listed

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Product Specification

Specification

Q.T.S Standard

Available Options


Capacity


Voltage Class


Conductor

N/A


Cooling

Insulation System

C - Copper

Frequency

Self cooled (ANN)

N/A

60 Hz

50/60 Hz



220°C (150°C Rise)


Temperature Rise


150 ⁰C average rise

115 ⁰C, 80 ⁰C

N/A

Impregnation


Polyester Resin Dipped and Baked

10 to 500 HP

Taps

 0%, 50%, 65%, 80% & 100%

N/A

N/A


Enclosure Type

Seismic

1.2 kV

Sound Level

 Open Core & Coil

Type 1, 2, 3R, 4, 4X or 12 Enclosure 




Shipping


Lead Time

3 to 6 Weeks Typical

Expedited available


NEMA ST-20

N/A

Epoxy dipped and Baked

3 dB below CSA level

Canada Zone 6, USA Zone 4

Specific seismic requirement available

Bolted to skid, with nylon cover

Shrink wrap, special skid, export crating