Motor Start Current Calculator
FLA LRA Inrush & Breaker
$4.99 · Designed for iPad. Not verified for macOS.
MotorStartCurrent - professional calculator.
Sizing a breaker or wire for a new motor and need to know the inrush current before you pull the trigger? Enter HP, voltage, and phase to instantly compare starting methods and get breaker size and wire gauge per NEC 430 — so you spec it right the first time.
Enter motor HP, voltage, phase, efficiency, and power factor. Compare four starting methods side by side: DOL (6x FLA), Star-Delta (2x), Soft Starter (3x), and VFD (1.5x). Shows FLA, LRA, inrush kVA, recommended breaker size, and wire gauge per NEC Article 430.
FEATURES:
- Full load amps (FLA) calculation for single and three phase
- Locked rotor amps (LRA) for each start method
- Inrush kVA calculation
- NEC 430 breaker sizing recommendation
- Wire gauge suggestion per NEC ampacity tables
- Single phase and three phase support
Built for electricians, controls engineers, and maintenance technicians. Works offline.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
Bug fixes and performance improvements.
The developer, Shanghai Sheyuan Network Technology Co., Ltd., indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Shanghai Sheyuan Network Technology Co., Ltd.
- Size
- 912.4 KB
- Category
- Utilities
- Compatibility
Requires iOS 17.0 or later.
- iPhone
Requires iOS 17.0 or later. - iPad
Requires iPadOS 17.0 or later. - Mac
Requires macOS 14.0 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- Copyright
- © 2026 Sheyuan Inc.
