FR-BU2-H75K 400V Brake Unit without Brake Resistor

Overview

FR-BU2-H75K is a 400V-class high-power braking unit, with a voltage adaptable to three-phase 400V class and a rated power of 75kW. It is suitable for the needs of high-power equipment such as mining and port loading and unloading. Up to 10 units can be operated in parallel, and the parallel connection does not exceed the overcurrent tolerance of the connected inverter. It can be connected to inverters without built-in braking transistors, and is used with GRZ G-shaped, FR-BR, MT-BR5 Using other types of external braking resistors can achieve stronger braking capabilities than simply external braking resistors.

FAQ:

1.What is the minimum resistance value of the discharge resistor required by FR-BU2-H75K? How many watts of continuous allowed power can it reach?

1. Minimum resistance value of the discharge resistor: The braking unit requires the minimum resistance value of the discharge resistor to be 6.5 ohms. This resistance standard is the key to ensuring the efficient and stable operation of its discharge function, and to avoid excessive loop current from damaging the internal components of the unit due to too small resistance.
2. Continuous allowable power: Its continuous allowable power is 7500 watts (7.5 kilowatts). This power parameter determines the discharge power load that the braking unit can stably carry under continuous operating conditions, adapting to the continuous consumption demand of regenerated electric energy in high-frequency braking scenarios of 75kW-level equipment.

2.FR-BU2-H75K is suitable for GRZ G-shaped, FR-BR and other types of braking resistors. How to choose the corresponding braking resistor model according to the braking torque requirement of the 75kW equipment?

Core logic: First convert the braking torque into braking power/current, ensure that the resistance value is ≥6.5Ω and the power matches the demand
GRZ G type (requires series adaptation to 400V):
8 pieces GRZG300 (8Ω): normal braking torque
12 pieces GRZG400 (24Ω): small torque/low frequency braking
6 pieces GRZG400 (2Ω): need to be adjusted in parallel to ≥6.5Ω, suitable for high torque/high frequency braking
FR-BR type (400V only):
FR-BR-H75K (6.5Ω/7500W): full load high frequency braking
FR-BR-H55K (24Ω/3910W): medium and low torque
FR-BR-H30K (40Ω/1990W): small torque/auxiliary braking

3.In addition to natural cooling, does FR-BU2-H75K support additional forced cooling devices to adapt to high-temperature industrial scenarios?

FR-BU2-H75K is designed for natural cooling:

1. Install an axial flow fan/cooling fan in the cabinet and reserve air ducts to prevent hot air from returning;
2. The directional fan blows directly into the heating core area, avoiding the wiring terminals and preventing dust accumulation.
3. No need to modify the internal circuit, suitable for high temperature scenarios >50℃