Calculators

Motors & Protection calculators

Motors and protection: FLA, branch circuits, overcurrent devices, overloads, and multi-motor feeders per NEC 430.

6 calculators in this family

Calculator

Motor Branch Circuit Sizer

Gauge-picked conductor at 125% FLA, ground reference, conduit fill hint and voltage at motor. 6 inputs, 4 outputs with grouped results.

Outputs: Min conductor ampacity · Chosen gauge adequate (1=yes) · Drop at motor

Calculator

Estimate FLA from HP, efficiency and PF, cross-checked against the NEC Table 430.250 dataset. 4 inputs, 5 outputs with grouped results.

Outputs: Estimated full-load current · NEC 430.250 table FLA · Estimate vs table

Calculator

Overload pickup at 115/125% FLA per NEC 430.32 with service-factor and temperature-rise selection. 4 inputs, 3 outputs with grouped results.

Outputs: Overload pickup · Setting band low · Setting band high

Calculator

Feeder for up to five motors: 125% largest + rest per NEC 430.24, plus other load, standard main. 8 inputs, 5 outputs with grouped...

Outputs: Motor total · Feeder ampacity · Feeder kVA

Calculator

Continuous vs noncontinuous, motor inrush reference, standard NEC 240.6 size via dataset ceiling lookup. 4 inputs, 4 outputs with grouped results.

Outputs: Sized load · Standard OCPD size · Motor branch calc

Calculator

Drive input current from motor HP with efficiency, feeder at 125%, and the reactor call. 5 inputs, 3 outputs with grouped results.

Outputs: Drive input current · Feeder at 125% · Add line reactor (1=yes)