3-Phase Motor Torque Calculator

3-Phase Motor Torque Formula:

\[ Torque = \frac{Current \times Voltage \times Efficiency \times 9550}{RPM \times \sqrt{3} \times Power\ Factor} \]

Current (I):

Voltage (V):

Efficiency:

(0-1)

RPM:

rev/min

Power Factor:

(0-1)

Torque:

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1. What is 3-Phase Motor Torque?

Torque in a 3-phase motor is the rotational force produced by the motor. It's a crucial parameter for determining the motor's ability to perform work and is directly related to the current and voltage supplied to the motor.

2. How Does the Calculator Work?

The calculator uses the 3-phase motor torque formula:

\[ Torque = \frac{Current \times Voltage \times Efficiency \times 9550}{RPM \times \sqrt{3} \times Power\ Factor} \]

Where:

\( Current \) — Motor current in Amperes (A)
\( Voltage \) — Supply voltage in Volts (V)
\( Efficiency \) — Motor efficiency (0-1)
\( RPM \) — Motor speed in revolutions per minute
\( Power\ Factor \) — Ratio of real power to apparent power (0-1)
9550 — Conversion constant

Explanation: The formula accounts for the electrical power input, motor efficiency, and converts it to mechanical torque output considering the motor's speed.

3. Importance of Torque Calculation

Details: Accurate torque calculation helps in motor selection, performance evaluation, and ensuring the motor can handle the required mechanical load without stalling or overheating.

4. Using the Calculator

Tips: Enter current in Amperes, voltage in Volts, efficiency and power factor as decimals between 0-1, and RPM in revolutions per minute. All values must be positive.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical power factor for motors?
A: Induction motors typically have power factors between 0.85-0.9 at full load, lower at partial loads.

Q2: How does torque vary with speed?
A: In AC motors, torque is inversely proportional to speed for a given power input.

Q3: What affects motor efficiency?
A: Efficiency depends on motor design, load, quality of materials, and operating conditions.

Q4: Why is √3 in the formula?
A: √3 accounts for the phase difference in 3-phase power systems (line-to-line vs line-to-neutral voltage).

Q5: What's the 9550 constant?
A: It's the conversion factor from watts to Nm when combined with RPM (60/(2π) × 1000).