Motor Winding Calculator
A motor winding calculator that computes coil turns, synchronous RPM, back-EMF, and Kv constant for DC, BLDC, AC induction, and stepper motors. Features an interactive SVG stator cross-section diagram with color-coded phase slots, star/delta connection visualization, and wire gauge selection with slot fill analysis. Free, no signup required.
Design Parameters
Calculation Results
15 turns/coil × 2 coils × 3 phases = 90 total turns
Winding Visualization
Stator Cross-Section
Winding Distribution
Connection Diagram
Slot Assignment
Wire Selection
Need 30 turns/slot but only 0 fit — increase slot size or use thinner wire
AWG Reference Table
| AWG | Diameter | Max A | Ω/m |
|---|---|---|---|
| 14 | 1.628 mm | 5.9 A | 0.00828 Ω |
| 18 | 1.024 mm | 2.3 A | 0.02095 Ω |
| 22 | 0.644 mm | 0.92 A | 0.05296 Ω |
| 26 | 0.405 mm | 0.361 A | 0.1339 Ω |
| 30 | 0.255 mm | 0.142 A | 0.3385 Ω |
| 34 | 0.16 mm | 0.056 A | 0.8561 Ω |
| 38 | 0.101 mm | 0.022 A | 2.164 Ω |
⚠️ Warning: Required 30 turns/slot but only 0 fit. Consider thinner wire or larger slots.
AWG 10 (2.588 mm) × 2.7 m = 127.3 g Cu
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What is a Motor Winding Calculator?
A motor winding calculator determines the number of coil turns needed for a given motor design based on supply voltage, target RPM, magnetic flux density, and core dimensions. It calculates key parameters including synchronous speed (RPM = 120f/P), back-EMF, winding factor, and Kv constant. This tool supports DC brushed, BLDC (brushless DC), AC induction, and stepper motor types with interactive stator cross-section diagrams showing phase slot assignments and star/delta connection layouts.
How to Use This Calculator
- Select your motor type (DC, BLDC, AC Induction, or Stepper) or choose a preset like NEMA 17 or BLDC 2212
- Set the number of poles and slots for your stator configuration
- Enter supply voltage, target RPM, magnet type, and core area
- View calculated turns per coil, actual RPM, back-EMF, and Kv constant in the results panel
- Switch to Visualization tab to see the interactive stator diagram and connection layout
- Use the Wire Selection tab to find the optimal AWG gauge based on target current and slot dimensions
Frequently Asked Questions
How do I calculate the number of turns for a BLDC motor?
For a BLDC motor, the turns per coil are calculated using the EMF equation: E = 4.44 × f × N × Φ × Kw, where f is electrical frequency, N is turns, Φ is magnetic flux, and Kw is the winding factor. Enter your supply voltage, target RPM, flux density, and core area, and the calculator will determine the optimal turns per coil.
What is the difference between star (Y) and delta (Δ) connection?
In star (Y) connection, phase voltage equals line voltage divided by √3 (about 57.7% of line voltage), resulting in more turns with thinner wire. In delta (Δ) connection, phase voltage equals line voltage, requiring fewer turns but thicker wire. Star is common for high-voltage motors; delta for high-current applications.
How does the number of poles affect motor RPM?
Synchronous RPM is inversely proportional to the number of poles: RPM = 120 × frequency / poles. A 2-pole motor at 60Hz runs at 3600 RPM, while a 4-pole motor runs at 1800 RPM. More poles give lower speed but higher torque for the same power.
What wire gauge should I use for motor winding?
Wire gauge depends on the target current and available slot space. The calculator recommends an AWG gauge based on your current requirement, then checks if the required turns fit in the available slot area considering the fill factor (typically 40-55%). A current density below 8 A/mm² is recommended for continuous operation.
What is the winding factor and why does it matter?
The winding factor (Kw) is the product of the distribution factor and pitch factor, typically between 0.85 and 0.96. It represents how effectively the winding produces a sinusoidal magnetic field. A higher winding factor means better utilization of the stator slots and more efficient torque production.