ABB NBRA-656C Brake Chopper Module

Technical Dossier

Product Details And Specifications

ABB NBRA Series Brake Choppers Technical Notes

The ABB NBRA series brake chopper modules are dedicated dynamic braking units designed for use with ABB ACS-family AC drives, including the ACS355, ACS550, ACS580, ACS800, and ACS880 platforms. These modules are deployed globally in heavy industrial environments — chemical processing plants, nuclear facility auxiliary systems, oil refineries, pulp and paper mills, and offshore platforms — where controlled deceleration of high-inertia loads is a critical process requirement. The NBRA series provides a low-impedance discharge path for regenerative DC bus energy during motor braking, protecting the drive inverter from overvoltage trips and enabling precise stop control without grid feedback capability.

ABB brake choppers in the NBRA range are frame-matched to specific drive power ratings and DC bus voltage levels (typically 510–770 V DC for 400 V AC input systems). Each unit connects directly to the drive's DC bus terminals and interfaces with an external braking resistor sized to the application's duty cycle and peak braking power.

The Evolution of NBRA Architecture

ABB introduced dedicated external brake chopper modules for the ACS series in the early 2000s as drive power ratings scaled beyond the internal braking transistor capacity of compact frames. Early NBRA units (NBRA-652C through NBRA-655C) targeted the ACS550 and ACS800 mid-range platforms, operating at fixed switching frequencies with analog fault relay outputs. As the ACS880 and ACS580 platforms were introduced (2012–2016), the NBRA lineup was extended with higher-current variants (NBRA-664C, NBRA-668C) and revised gate-drive circuitry for improved IGBT reliability under repetitive duty cycles.

Compatibility across generations is frame-specific: NBRA units are not interchangeable between ACS550 and ACS880 without verifying DC bus voltage range, chopper current rating, and terminal block configuration. For installations where original NBRA variants have reached end-of-life, ABB's BRCR series and third-party equivalents may serve as functional replacements, but require engineering validation of switching threshold and resistor interface parameters.

NBRA Full Catalog & Functionalities (SKU List)

The following SKUs represent the verified ABB NBRA brake chopper range. Each unit is classified by its primary application and power tier:

NBRA-652C: Brake chopper for ACS550, frame R4, 15–22 kW, 400 V AC input systems.
NBRA-653C: Brake chopper for ACS550, frame R5, 30–45 kW, extended duty cycle rating.
NBRA-654C: Brake chopper for ACS550/ACS800, frame R6, 55–75 kW, dual IGBT configuration.
NBRA-655C: Brake chopper for ACS800, frame R7, 90–132 kW, high-inertia load applications.
NBRA-656C: Brake chopper for ACS800/ACS580, frame R8, 160–200 kW, industrial crane and hoist duty.
NBRA-657C: Brake chopper for ACS800, frame R8i, 200–250 kW, parallel bus bar connection.
NBRA-658C: Brake chopper for ACS880, frame R8i, 250–315 kW, reinforced gate driver board.
NBRA-659C: Brake chopper for ACS880, frame R9, 355–400 kW, high-frequency switching variant.
NBRA-664C: Brake chopper for ACS880, frame R6, 55–75 kW, updated IGBT module generation.
NBRA-668C: Brake chopper for ACS880, frame R7, 90–132 kW, compatible with ACS880-07 cabinet drives.
NOCH0016-62: External braking resistor assembly, 16 Ω, matched to NBRA-652C/653C applications.
NOCH0030-65: External braking resistor assembly, 30 Ω, matched to NBRA-654C/655C, IP21 enclosure.
NOCH0070-65: External braking resistor assembly, 70 Ω, matched to NBRA-656C/657C, forced-air cooled.
NOCH0100-65: External braking resistor assembly, 100 Ω, matched to NBRA-658C/659C, stainless steel housing.
SACE-NBRA-BRK: Brake chopper interface kit, includes DC bus fuse, cable lug set, and mounting hardware for NBRA-65x series field installation.