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How to Select Circuit breaker for the High Efficiency Motor? 

To select circuit breaker for the High efficiency motor, Please follow as specified. 

1) If the subtransient starting current is known (indicated by the motor manufacturer) and is less than 19 In motor (A peak). In this case, the starter components can be selected directly from the coordination tables from the latest Complimentary Technical Catalog, whatever the value of the starting current (for Id > 7.5 In).
Example: for a 110 kW 380/415 V 3-phase motor, the selected components are: NSX250-MA220/LC1-F225/LR9-F5371

2) If the subtransient starting current is unknown or greater than 19 In motor (A peak).In this case, the value used for the motor power in the coordination tables should be increased by 20 % to satisfy optimum starting and coordination conditions.
Example: for a 110 kW 380/415 V 3-phase motor, the selected components are
those for a motor power of 110 + 20 % = 132 kW: NSX400 Micrologic 4.3M/LC1-F265/LR9-F5371

Attached document for further reference. 
 
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