Brushless Motor Torque Calculator

A brushless motor can give strong torque with low loss. But how do you find its torque? Our brushless motor torque calculator makes it easy. You can use torque, current, speed, or power data. The tool then gives torque in N·m.

This tool can help with motor tests, machine design, robots, drones, pumps, fans, and other motor work.

What Is Brushless Motor Torque?

Torque is the twist force of a motor. Think of a wrench. A longer wrench gives more turning force. A motor does the same job with its shaft.

Brushless motor torque tells you how hard the shaft can turn a load. This value helps you pick a motor and check its load needs.

Brushless Motor Torque Formula

The main brushless motor torque equation is:

T = Kt × I

Here, T is torque in N·m. Kt is the torque constant in N·m/A. I is motor current in A.

If you know Kv, use:

Kt = 60 / (2π × Kv)

Then:

T = 60I / (2π × Kv)

If you know power and speed, use:

T = 60P / (2π × N)

Here, P is power in watts. N is speed in RPM.

The calculator also uses this common form:

T ≈ 9550 × P(kW) / N(RPM)

The exact form is T = 60P / (2πN). This is the key electric motor torque calculation formula used in the power and RPM method.

How to Use Online Brushless Motor Torque Calculator

1. Pick your method. Choose Kt and current, Kv and current, or power and RPM.
2. Enter your motor data. Use the units shown in the calculator.
3. Check your values. Current must be zero or more. Kt, Kv, power, and RPM must be above zero.
4. Click Calculate. The tool converts units when needed.
5. Read your result. You’ll get torque in N·m. The tool also gives useful torque unit conversions.

Example Brushless Motor Torque Calculation

Suppose a brushless motor has Kt = 0.05 N·m/A. The motor draws 10 A.

Use:

T = Kt × I

T = 0.05 × 10

T = 0.50 N·m

So, the motor torque is 0.50 N·m.

Now, let’s use Kv. Say Kv is 1000 RPM/V. Current is 10 A.

First:

Kt = 60 / (2π × 1000)

Kt ≈ 0.00955 N·m/A

Then:

T = 0.00955 × 10

T ≈ 0.0955 N·m

For power, say the motor gives 1 kW at 3000 RPM.

T = 9550 × 1 / 3000

T ≈ 3.18 N·m

These examples show the main ways of calculating torque of a motor.

Final Verdict

A brushless motor torque calculator saves time and cuts math work. Use T = Kt × I when Kt and current are known. Use the Kv form when Kv is given. Use the power form when power and RPM are known.

The tool works as an electric motor torque calculator, torque calculator for motor work, and motor torque calculator to N·m. Enter correct motor data and check the units for a sound result.

FAQs

What is the brushless motor torque equation?

The main equation is T = Kt × I. Kt is in N·m/A, while I is in A.

How do you calculate torque of a motor?

Use T = Kt × I. If power and RPM are known, use T = 60P / (2πN).

How do I calculate electric motor torque?

You can use Kt and current, or use power and RPM. Pick the method that matches your motor data.

How do I convert motor torque to N·m?

Convert the torque value to N·m before comparing motor results. One N·m equals about 10.197 kg·cm.

What is the difference between Kt and Kv?

Kt links current to torque. Kv links voltage to motor speed. The calculator uses Kt = 60 / (2πKv).

Can I use this for a brushless DC motor?

Yes. The calculator supports brushless DC motor torque calculations. It uses the torque equations shown above.