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Users often confuse the differences between electromagnetic braking, regenerative braking, and dynamic braking, which can lead to selecting the wrong accessories. Understanding these distinctions is crucial for proper system design and operation.

Dynamic braking involves a resistor that dissipates energy during faults, emergency stops, or power outages, helping to stop the servo motor more quickly by converting kinetic energy into heat. This method is especially useful when immediate stopping is required, but it requires external control via relays.

Regenerative braking, on the other hand, sends the energy generated during deceleration back to the DC bus through an inverter, where it can be stored or used elsewhere. This process is automatic and only works when the system is operating normally. It's ideal for reducing energy waste but cannot be used during faults or power failures.

Electromagnetic braking uses mechanical means to lock the motor shaft, ensuring the motor remains stationary even when power is removed. It’s commonly used in applications where holding torque is essential, such as lifting systems or conveyor belts.

The main differences between these braking methods are as follows:

• Power Requirements: Regenerative braking requires the system to be operational, while dynamic and electromagnetic brakes work without power.
• Control Mechanism: Regenerative braking is automatic, whereas dynamic and electromagnetic brakes need external relay control.
• Usage Scenarios: Electromagnetic brakes should be activated after the servo is turned off to prevent overload, and dynamic brakes should be used after the system is powered down to avoid overheating the resistor.

When choosing the right accessory, consider the following factors:

• For systems like conveyors or lifting devices that require rapid stopping, dynamic braking is recommended. These systems often have high inertia, so selecting the appropriate resistor based on load weight and motor speed is essential.
• If maintaining a static position with long stopping time is necessary, using a motor with an electromagnetic brake is preferable. Relying solely on the servo's self-locking function may cause overheating or amplifier overload.
• Mitsubishi servos come with built-in regenerative braking units, but frequent use may cause high DC bus voltage. In such cases, a separate regenerative resistor might be needed. Always refer to the user manual for specific requirements. The number of brakes listed is based on no-load conditions, so actual selection should account for the inertia ratio of the system and the motor.

By carefully analyzing your application and understanding the functions of each braking method, you can ensure optimal performance and safety in your servo system.