Description

Overview

Dynamic braking resistor is designed to safely absorb and dissipate excess regenerative energy generated during motor deceleration in variable frequency drive (VFD) and inverter systems. This aluminum housed braking resistor provides reliable energy conversion, efficient heat dissipation, and stable braking performance for industrial motor control applications.

With a robust aluminum enclosure and optimized thermal design, this resistor ensures consistent operation under continuous load conditions. It is widely used in VFD systems, AC motor drives, automation equipment, and power conversion applications where controlled braking and energy dissipation are required.

Available with different resistance values and power ratings, our dynamic braking resistor solutions can be customized to meet various drive system requirements, including high inertia loads, frequent acceleration and deceleration cycles, and demanding industrial environments.

What Is a Dynamic Braking Resistor?

A dynamic braking resistor is a power resistor used in motor drive systems to absorb and dissipate regenerative energy generated when an electric motor slows down or stops.

During deceleration, the motor can operate as a generator and feed electrical energy back into the variable frequency drive (VFD) DC bus. If this excess energy cannot be released, it may cause DC bus overvoltage faults and trigger drive protection.

A dynamic braking resistor provides a controlled path to convert this regenerated electrical energy into heat, allowing the motor to decelerate safely and smoothly.

Dynamic braking resistors are commonly used in:

• Variable frequency drives (VFDs)
• AC motor control systems
• Industrial automation equipment
• Hoisting and lifting equipment
• Conveyors
• Centrifuges
• Inverters and power conversion systems

How Does a Dynamic Braking Resistor Work?

When a motor decelerates, the stored mechanical energy is converted into electrical energy and returned to the VFD.

The braking process includes:

1. The motor generates regenerative energy during deceleration.
2. The VFD detects an increase in DC bus voltage.
3. The braking circuit activates the resistor.
4. The resistor converts excess electrical energy into heat.
5. The motor achieves controlled and stable braking.

This process helps prevent:

• DC bus overvoltage
• Unexpected drive shutdown
• Excessive braking time
• System instability

How to Select a Dynamic Braking Resistor?

The correct braking resistor depends on several factors:

1. Motor Power

The motor rating determines the required braking capacity.

2. VFD Specifications

The resistor selection should match the VFD manufacturer’s recommended resistance value and braking power.

3. Duty Cycle

Frequent braking applications require higher power handling capability.

4. Installation Environment

Cooling conditions, cabinet space, and ambient temperature should be considered.

Applications