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What CPT or Control Power Transformer should I use with the S611 soft starter?

There are two versions of power demand requirements for the S611 soft starters.

Frame A-D  require 85VA to seal and 600VA for inrush for 50ms

Frame E-F require 115VA to seal and 1200VA for inrush for 50ms

The control power for the S611 has to be maintained to at least 90% of rating so using the formula and chart for sizing CPTs dictates that


Frames A-D can use a 200VA CPT

Frames E-F can use a 250VA CPT

For Eaton S611s in enclosures in our Enclosed Control line we just always use the 250VA transformer.


See Industrial Control Transformers catalog for picking CPTs accordingly.