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How do I select the proper Buck & Boost Transformer to go from 208V to 230V, or from 230V to 208V?

Issue:

Procedure for selection of SquareD/Schneider Electric Buck and Boost Transformers

Product Line:

LV Transformers

Environment:

Applies to all SquareD/Schneider Electric Buck and Boost Transformers

Cause:

Requirement to change a source voltage to a higher or lower load voltage

Resolution:

Use Buck & Boost catalog 7414CT0001, Buck & Boost `slide rule` 7414SP9901, or:

1. If load is single phase:
A. Multiply 24 volts times the load amperage needed to obtain VA of Buck & Boost Transformer
B. Choose a `SV43` transformer of next larger standard size above the VA obtained in A.
Example: If load is 11 amperes, multiply 11 x 24V = 264VA, choose catalog number 500SV43B
C. Connect using wiring diagram #4 in Buck & Boost literature
2. If load is three phase 3-wire:
A. Use same procedure as in single phase except two transformers must be used.
Example: If load is 27 amperes, multiply 27 x 24V = 648VA, choose (2) catalog number 750SV43F
B. Connect using wiring diagram #6 in Buck & Boost literature
3. If load is three phase 4-wire:
A. Multiply 12 volts times the load amperage needed to obtain VA of Buck & Boost Transformer
B. Choose three `SV43` transformers, each of next larger standard size above the VA obtained in A.
Example: if load is 11 amperes, multiply 11 x 12 = 132VA, choose (3) catalog number 150SV43A
C. Connect using wiring diagram #7 in Buck & Boost literature Warning: Three phase 4-wire loading requires a 3-phase 4-wire primary source for wiring diagram #7. Attempts to create a neutral with Buck & Boost Transformer connections can result in damage to load equipment!