High-Capacity Motor Braking Solution

The Fuji BU90-4E Dynamic Braking Unit Kit is an essential accessory for high-power Fuji 400V Variable Frequency Drives (VFDs). This kit is designed to efficiently dissipate the regenerative energy created when an AC motor is rapidly decelerating, ensuring quick and safe stopping of high-inertia loads without triggering VFD overvoltage faults.

The single BU90-4E unit covers two motor ratings (75kW ), but requires a specific, correctly-sized Braking Resistor (DB) to be selected below for optimal performance.

Key Features

Broad Compatibility: Works seamlessly with Fuji FRENIC-MEGA, FRENIC-ACE, and other 400V VFD series, particularly for high-power applications.
Safety and Compliance: Ensures controlled motor stops, protecting your VFD and machinery from damage.
Simple Installation: Designed for easy integration into control panels.

Technical Specifications & Component Pairing

The core BU90-4E unit is the same for both applications, but the resistance value changes to handle the different regenerative energy profiles of the 75kW motors.

Option Selection (Kit)	BU Unit Model	Required Resistor Model	Resistance Value (?)
75kW	BU90-4E	DB75-4C	6

Outline Dimensions (BU Unit and Resistors)

Verify clearances for your control panel using the dimensions below (all measurements in millimeters).

Component	Width (mm)	Height (mm)	Depth (mm)	Weight (kg)
Braking Unit (BU90-4E)	180	400	180	8.5
Resistor (DB75-4C)	120	1100	160	22

Downloads

Braking Unit Instruction Manual
Braking Resistor Instruction Manual

Engineering Tools

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Fuji BU90-4E Dynamic Braking Unit Kit

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