Description
ABB REM545BG227AAAA Machine Protection Terminal
Product Overview
The ABB REM545BG227AAAA belongs to the REM 545 family of rotating machine terminals developed for integrated protection, control, measurement, and supervision of electrical machines. Rather than functioning as a conventional PLC input/output card, the ABB REM545BG227AAAA combines protection algorithms, measurement channels, programmable logic, switching-device control, disturbance recording, and self-supervision in one protection terminal. ABB documentation identifies the REM 545 for generator and generator-transformer units in small and medium-power diesel, hydroelectric, and steam power plants, as well as large medium-voltage synchronous and asynchronous motors used in applications such as pumps, fans, mills, and crushers.
From an engineering standpoint, the ABB REM545BG227AAAA is most useful where an existing electrical protection architecture already depends on the REM 54 platform. The terminal accepts conventional current-transformer inputs, with the researched configuration specified for 1/5 A current inputs, and uses a 110–240 VAC or 110–220 VDC auxiliary supply. Available machine-protection functions include phase and earth-fault overcurrent protection, negative-sequence protection, voltage protection, frequency protection, differential protection, thermal overload, underexcitation, underimpedance, reverse/underpower protection, motor start-up supervision, and synchro-check functions, with the actual function set dependent on hardware and functionality level.
For plant engineers, the important point is that the REM 545 sits between the field CT/VT system and the higher-level electrical control or substation automation system. It can provide local HMI operation, switching-object control, interlocking, event information, condition monitoring, and communication to supervisory equipment. The platform also incorporates PLC-style logic functions, allowing certain sequence and automation tasks to remain inside the protection terminal rather than being reconstructed entirely in a separate controller.
The REM545BG227AAAA configuration is documented with 25 binary inputs and 18 relay outputs, giving it substantially more I/O capability than a basic protection relay. Disturbance recording is also available on the platform, supporting post-event analysis of electrical faults and machine behavior.
One procurement warning matters here: this is a legacy ABB platform. A part number match alone does not establish interchangeability. Functionality level, software revision, CT/VT configuration, I/O allocation, communication arrangement, and stored protection settings all need to be checked before installing a replacement unit. ABB’s own documentation shows that REM 543 and REM 545 configurations can vary according to hardware and selected functionality level.
Product Introduction
A failed machine protection relay is not the place to improvise a generic PLC replacement. The ABB REM545BG227AAAA was designed around rotating-machine protection requirements, including fault protection, abnormal operating conditions, motor starting supervision, measurement, control, and event analysis.
For a DCS system upgrade, electrical protection retrofit, or legacy replacement, the practical question is not simply whether the replacement relay has the same physical dimensions. The CT/VT inputs, auxiliary supply, I/O assignment, protection settings, communication interface, and application logic must match the existing protection scheme.
Key Technical Specifications
| Parameter | Value |
|---|---|
| Product Model | |
| Manufacturer / Brand | ABB |
| Product Series | REM 545 |
| Product Family | RE 500 |
| Product Type | Rotating machine protection and control terminal |
| Primary Application | Generator, generator-transformer, synchronous motor, asynchronous motor protection |
| Nominal Current Inputs | 1 A / 5 A |
| Current Input Type | Conventional current transformer |
| Auxiliary Supply | 110–240 VAC or 110–220 VDC |
| Binary Inputs | 25 optocoupled inputs |
| Relay Outputs | 18 |
| Output Types | HSPO, PO, SO |
| Communication | SPA-bus / LON-bus / Modbus RTU, depending on configuration |
| Disturbance Recording | 16 analog + 16 binary channels |
| Measurement | Current, voltage, frequency, power, energy, power factor and related quantities |
| Protection Functions | Overcurrent, earth fault, differential, voltage, frequency, thermal, negative sequence, excitation, power and motor-start functions |
| Programmable Logic | Integrated PLC-style logic and sequence functions |
| Local Interface | Graphic HMI / front-panel operation |
| Manufacturer Location | ABB Oy Distribution Automation, Finland |
| Product Weight | Approximately 7.7 kg according to ABB product data |
| Product Status | Legacy / no longer an active current-generation product |
The detailed protection-function set depends on the selected REM 545 functionality level and hardware configuration. ABB documentation specifically describes separate protection, measurement, control, condition-monitoring, communication, and standard function groups rather than treating every REM 545 unit as having an identical software feature set.
REM545BG227AAAA
Major Features and Advantages
Integrated rotating-machine protection
The primary strength of the REM 545 architecture is its focus on rotating electrical machinery. Protection functions extend well beyond simple overcurrent. Depending on the configured functionality, the platform supports earth-fault, negative-sequence, voltage, frequency, differential, thermal, excitation, impedance, power, and motor-start protection. This makes it suitable for applications where generator or motor behavior must be evaluated as a complete electrical system rather than through one isolated fault element.
1 A / 5 A CT compatibility
The configuration is specified for conventional 1 A / 5 A current-transformer inputs. This matters during replacement because the CT secondary rating is not a cosmetic specification. A relay with the wrong input configuration can create a protection-engineering problem even if its enclosure and communication interface appear compatible.
Extensive hardwired I/O
With 25 binary inputs and 18 relay outputs, this configuration can interface directly with a substantial number of breaker, disconnector, alarm, trip, interlock, and status signals.
That I/O capacity also reduces dependence on external auxiliary relays for some machine-control arrangements. The actual terminal allocation still needs to be checked against the original drawings before replacement.
Integrated measurement and disturbance recording
The REM 545 measures electrical quantities required for protection and operational supervision. Its disturbance-recording capability provides analog and binary event information that can be useful when investigating generator trips, motor starting problems, breaker events, or abnormal network conditions.
Local and remote control
The terminal supports local indication and control of switching objects as well as communication with higher-level systems. ABB documentation describes local HMI operation, remote control, status indication, interlocking, and communication functions as part of the REM 54 architecture.
Integrated programmable logic
The REM 545 platform contains PLC-style logic capabilities for automation and sequence functions. This can be particularly useful in older electrical systems where protection, control, and interlocking logic were intentionally consolidated into the machine terminal.
The downside is equally important: replacing the physical terminal without recovering and validating the original logic can leave the machine protection scheme incomplete even when the relay powers up normally.
Related Products
- ABB REM543 — Closely related REM 54 machine terminal with a different hardware/I/O configuration. Useful when comparing the smaller REM platform against the REM 545.
- ABB REM545 — Same primary machine-terminal family without specifying the complete ordering suffix. Useful as a family-level reference, but the exact hardware code must be verified.
- ABB REM545BG225AAAA — Another REM 545 configuration with 5 A-class current input identification in historical procurement records; compare the complete ordering code before substitution.
- ABB REF543 — Feeder protection and control terminal from the same broader ABB protection generation, but intended for feeder applications rather than being treated as a direct REM 545 replacement.
- ABB RET521 — Transformer protection and control platform; application differs substantially from rotating-machine protection.
- ABB REG216 — Generator and motor protection family used in older ABB protection architectures; useful when assessing legacy protection-system migration.
- ABB SPA-ZC 400 — Communication adapter associated with IEC 61850 connectivity for compatible older ABB protection terminals; verify the exact terminal and firmware architecture before assuming support.
- ABB RE 500 Series — Broader protection and control platform encompassing multiple application-specific terminals.
FAQ
Can I hot-swap the ABB ?
Do not treat it as a routine hot-swappable PLC module. This is a machine protection terminal connected to CT/VT circuits, trip circuits, breaker controls, and protection logic. The replacement procedure must follow the site’s approved protection-maintenance procedure, including appropriate isolation and CT secondary precautions.
Does the support firmware v3.1?
A generic “v3.1” compatibility statement cannot be confirmed for this exact ordering code from the documentation reviewed. REM 545 documentation identifies software revisions and functionality levels, but the replacement unit’s actual software revision should be read from its identification/configuration information. Do not assume that two units with the same hardware part number contain identical application software.
Is this a PLC or DCS I/O module?
No. It is a machine protection and control terminal. It contains programmable logic and substantial I/O capability, but its primary purpose is electrical machine protection and control rather than serving as a general-purpose PLC/DCS I/O rack module.
What should be checked before replacing an existing REM 545?
At minimum, verify:
- Complete part number:
- Hardware and software revision
- CT secondary rating and measurement arrangement
- VT/voltage-divider configuration
- Protection functionality level
- Binary input/output wiring
- Trip-circuit supervision arrangement
- Communication interface and protocol
- Protection settings and application logic
- Disturbance-recording configuration
ABB documentation specifically notes that available functionality depends on hardware configuration and selected functionality level.
Does the retain protection logic?
The terminal supports programmable logic and configuration-based protection functions. However, the physical replacement unit should not be assumed to contain the same site-specific logic or settings as the failed unit. Before commissioning, recover the existing configuration wherever possible and perform a documented functional check.
What does “New Surplus” mean for this part?
“New Surplus” describes the commercial condition of a particular unit; it does not by itself prove that the relay has never been powered, configured, or installed. For a protection relay, procurement inspection should include the nameplate, complete ordering code, serial information, visible condition, auxiliary-power test, display/HMI operation, self-supervision status, and configuration/software information.
Is the ABB suitable for marine applications?
The REM 54 documentation identifies compact marine unit-protection applications for the REM 543/REM 545 family. However, marine project acceptance still depends on the vessel/class requirements, exact hardware configuration, installation conditions, and project certification. Do not infer project approval solely from the REM 545 family name.
Procurement and Compatibility Note
For a legacy replacement, the safest purchasing practice is to treat the complete ordering code as only the first identification layer. Photograph the nameplate, record the hardware/software revision, obtain the existing configuration file if available, and compare the CT/VT and I/O drawings before installation.
ABB’s product data identifies as a REM 545 machine terminal and lists it as a spare-parts product with a 7.7 kg net weight.
For protection equipment, that verification step is worth the effort. A relay that powers up and communicates correctly can still be wrong for the machine if its protection functionality, CT/VT scaling, logic, or trip wiring does not match the original scheme.
