Dual Voltage Transformers 11.9-6.9kV
Dual Voltage Transformers
Transformers with dual voltage primaries have been widely employed as a means to reduce the number of transformers required to accommodate facilities with multiple primary voltage sources. Padmount, station, or secondary unit substation configurations may be provided with dual voltage capabilities thereby reducing the number of spare transformers inventoried as back-ups in critical load environments
There are several means in which to provide the dual voltage option.
Three phase dual voltage switches (also known as series/multiple switches) are available to allow for connection changes to the windings by way of a switch handle located on the outside wall of the transformer tank. They are however, no-load devices and therefore may only be operated while the transformer is deenergized.
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