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How to properly connect Square D low voltage single-phase dry type transformers rated for 240 x 480 - 120/240

Some Epoxy Resin Encapsulated Transformers have connection instructions on the nameplate that can be confusing.

Product Line:
LV Transformers

Applies to Single Phase Transformers with 480V x 240V primaries and 240/120V secondaries ONLY.


Wording:  "V On Lines"  and  "Connect"  on Epoxy Resin Encapsulated Transformer nameplates.

Connections depend on your application.

For 480V connect H2 and H3 together and apply primary 480V lines to H1 and H4
For 240V connect H1 and H3 together and connect H2 and H4 together, then apply 240V lines to H1 and H4

For 120/240 Volt 3-wire: Connect X2 and X3 together and bond to equipment ground and building ground. 240V outputs are X1 and X4, neutral is the X2/X3 connection
For 120 Volt 2-wire: Connect X2 and X4 together and bond to equipment ground and building ground. Connect X1 and X3 together. 120V hot line is the X1/ X3 connection, neutral is the X2/X4 connection

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