Essential Motor Braking Solution

The Fuji BU55-4E Dynamic Braking Unit Kit is an essential accessory for 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 BU55-4E unit covers two motor ratings (45kW and 55kW), 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.
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 BU55-4E unit is the same for both applications, but the resistance value changes to handle the different regenerative energy profiles of the 45kW and 55kW motors.

Option Selection (Kit)	BU Unit Model	Required Resistor Model	Resistance Value (?)
45kW	BU55-4E	DB45-4C	10
55kW	BU55-4E	DB55-4C	7.5

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 (BU55-4E)	150	320	160	5.5
Resistor (DB45-4C)	100	800	145	16
Resistor (DB55-4C)	100	950	145	18

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Fuji BU55-4E Dynamic Braking Unit Kit (45kW to 55kW, 400V Class)

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