Inputs
- Motor HP
- Line voltage
- Coil voltage
Motor Starter Sizing Tool
Input motor horsepower and voltage to automatically generate a coordinated motor starter.
Enter inputs to automatically resolve FLC, breaker, contactor, overload, and generated data.
InputsMotor HP, line voltage, coil voltage
Lookup OutputFLC, contactor, breaker, overload
Voltage Options240 or 480 V line, 24 or 120 V coil
Motor Range1 to 30 HP
Automatic motor starter sizing and coordination
This starter is generated directly from the same logic used in the workspace.
- At 1 HP @ 240 V: 4.2 A FLC, 15 A breaker, 10 A contactor, 5-10 A overload.
- At 30 HP @ 480 V: 40 A FLC, 100 A breaker, 60 A contactor, 20-40 A overload.
Change horsepower or voltage and the starter updates automatically.
Increasing motor size updates breaker, contactor, overload, and motor data together.
These changes are reflected directly in structured output data.
| Motor | FLC (A) | Breaker (A) | Contactor (A) | Overload Range (A) |
|---|---|---|---|---|
| 1 HP @ 240 V | 4.2 | 15 | 10 | 5-10 |
| 30 HP @ 480 V | 40 | 100 | 60 | 20-40 |
Geometry and data stay aligned because they are generated from the same logic.
Inputs and outputs
Motor requirements resolve the coordinated starter components and the reported outputs together.
Outputs
- FLC
- Contactor rating
- Breaker size
- Overload range
- Schematic
Lookup-driven starter design logic
A lookup table maps motor horsepower and voltage to the required electrical components.
Resolved logic
- Motor data comes from a lookup table with FLC based on HP and voltage.
- Contactor current is selected from the same lookup data.
- Breaker size is selected from the coordinated table output.
- Overload trip range is selected automatically.
- Coil voltage propagates into the contactor portion of the starter design.
Why that matters
This keeps breaker, contactor, overload, and motor aligned as one system. Changing motor requirements updates the entire starter automatically.
Coordinated selections are reflected directly in the resolved starter outputs.
| Motor | FLC | Breaker | Contactor | Overload |
|---|---|---|---|---|
| 1 HP @ 240 V | 4.2 A | 15 A | 10 A | 5-10 A |
| 5 HP @ 240 V | 15.2 A | 40 A | 20 A | 10-20 A |
| 15 HP @ 480 V | 21.0 A | 60 A | 40 A | 20-40 A |
| 30 HP @ 480 V | 40.0 A | 100 A | 60 A | 20-40 A |
Generated Data
The resolved starter produces usable engineering data that can be exported and kept aligned with the schematic.
Motor, breaker, contactor, and overload values are available as generated data from the same evaluated starter.
Exported data stays aligned with the visible result, which keeps reporting and downstream review in sync with the design.
Generated data can be exported as CSV or JSON.
| Component | Role | Resolved output |
|---|---|---|
| Motor | Load | 5 HP, 240 V, 15.2 A |
| Contactor | Control | 20 A contactor, 24 V coil |
| Circuit Breaker | Protection | 40 A, 3-pole, 240 V |
| Overload | Protection | 10-20 A range, class 10 |
Manual sizing versus LogiDraft
Motor starter sizing is a coordination problem. One change should update the whole starter definition consistently.
Look up, calculate, then reconcile
- Check FLC from a table.
- Select breaker and overload separately.
- Verify the contactor still matches the motor condition.
- Update notes and BOM data after the schematic changes.
One model resolves the starter
- Motor FLC, breaker, contactor, and overload come from coordinated logic.
- Changing HP or voltage updates the whole starter at once.
- Structured data exports stay aligned with the schematic.
- The result is faster to review and harder to mismatch.
Open the example and see the system in action
Open the example, change horsepower or voltage, and review the updated result.