Breakaway torque

Understanding Breakaway Torque: The Unsung Hero of Motor Starting

In the world of electric motors, torque is king. It's the force that drives rotation, enabling machines to perform tasks from simple stirring to complex industrial processes. But while continuous torque describes the sustained force a motor can deliver, breakaway torque, often overlooked, plays a crucial role in the very act of starting.

What is Breakaway Torque?

Breakaway torque, sometimes referred to as "starting torque", is the absolute minimum torque a motor needs to overcome static friction and begin rotating a load. Imagine a heavy door: You need to push harder initially to get it moving than to keep it moving at a steady pace. Similarly, a motor requires a specific amount of torque to overcome the initial resistance of a stationary load.

Why is Breakaway Torque Important?

Breakaway torque is critical for two key reasons:

1. Smooth Starting: A motor with insufficient breakaway torque will struggle to overcome static friction, resulting in stuttering starts, excessive wear and tear on the motor and load, and potential damage to the system. This is particularly important for loads with high inertia, like large conveyor belts or pumps.

2. Reliable Operation: A motor with enough breakaway torque ensures reliable starting even under challenging conditions, such as:

   • Low voltage: Voltage fluctuations can impact motor performance, making sufficient breakaway torque essential for successful starts.
   • Heavy loads: Starting a heavy load requires significantly more torque compared to lighter ones.
   • High friction: Loads with high friction, such as bearings with high wear, demand higher breakaway torque.

How to Determine Breakaway Torque Needs:

Knowing the exact breakaway torque requirements for a specific load is crucial for selecting the right motor. Factors to consider include:

• Load inertia: Heavier loads require more torque to get moving.
• Friction: Higher friction levels necessitate increased breakaway torque.
• Operating environment: Temperature, humidity, and dust can influence friction levels and impact breakaway torque needs.
• Voltage fluctuations: Anticipating voltage drops requires a motor with adequate breakaway torque to compensate.

Breakaway Torque vs. Continuous Torque:

While both torque types are vital, they serve distinct purposes:

• Breakaway Torque: Focuses on the initial start of the load.
• Continuous Torque: Describes the sustained force the motor can deliver while running.

A motor's datasheet typically provides both breakaway and continuous torque specifications. Selecting a motor with enough breakaway torque ensures smooth and reliable operation, even under challenging conditions.

In Conclusion:

While often overshadowed by continuous torque, breakaway torque plays a crucial role in ensuring a smooth and reliable start for any motor-driven application. Understanding its importance and selecting a motor with sufficient breakaway torque can prevent costly breakdowns and ensure optimal system performance.