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Does a 9070 Type T or TF Industrial Control Transformer (CPT) have any continuous overload capacity? What about momentary overloads due to high inrush loads (a coil on a contactor?)

Issue:
Control Transformers may experience momentary overloads on high inrush loads

Product Line:
LV Transformers

Environment:
Applies to 9070 T and TF type Control Transformers by SquareD/Schneider Electric

Cause:
Inductive loads such as Motors, Solenoids, and Transformers may produce high inrush currents when first energized


Resolution:

Transformers are 100% rated devices.  As such, they do not have any continuous overload capacity.  CPTs are specifically designed for momentary currrent draw in excess of it`s rating for high inrush type loads.  For directions on selecting the appropriate CPT for Contactor or Starter applications, begin with the Inrush VA and Sealed VA of the Contactor or Starter coil.  Then, see the Regulation chart and associated instructions on page 5 of the Industrial Control Transformer catalog, document # 9070CT9901, attached below.


 

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