ABB REM543/REM545 motor/generator protection and measurement device

Overall characteristics of the product

Input compatible with two collection methods

Conventional: CT (1A/5A), PT voltage transformer;

Sensor mode: Roche coil current sensor, voltage divider, connected through BNC shielded coaxial cable.

Human machine interface: two solutions – local fixed graphic LCD HMI; External independent display panel (powered separately, suitable for cabinet door split installation). The panel supports dynamic simulation MIMIC, programmable LED alarm, and local on/off operation.

Built in IEC61131-3 standard PLC function library, which can achieve interval interlocking and timing logic, and rely on LON bus to achieve logical interaction between devices, reducing hard wiring.

Recording capability: transient disturbance recording (up to 16 analog signals+16 digital signals), event recording, circuit breaker operation counting.

Optional RTD/mA module: collects stator, bearing, and ambient temperature; Provide 4 channels of 0-20mA analog outputs to interface with the dashboard and external PLC.

Communication interfaces: SPA bus, LON bus Modbus‑RTU； Front panel optical RS232 debugging port.

Application scenarios: diesel generators, hydro generators, steam turbine generators; High power high-voltage asynchronous/synchronous motor; Ship crew; Plant power generator transformer unit protection.

Hardware I/O architecture

Hardware version differentiation

Suffix A: No sensor input, only connected to regular CT/VT;

Suffix B: with sensor channel, supporting Roche coil and voltage divider;

Power supply module PS1: Two power supply options: AC110-240V/DC24-60V/DC110-220V.

I/O difference

Model number input power output (trip control) signal output

REM543 15:00 5-way bipolar power output 5-way NO/NC signal output

REM545 25 o’clock 9-way bipolar power output, 5-way NO/NC signal output

Optional RTD module: 8-channel RTD/DC analog input; 4-channel isolated 0-20mA analog output. The output is divided into three categories:

HSPO high-speed power output: used for circuit breaker tripping and closing;

PO power output: switch device control;

SO signal output: alarm, status signal, unable to drive circuit breaker coil.

Terminals and Machinery

Chassis: 1/2 19 inch rack, 6U height; Weighing approximately 8kg;

Protection: front panel IP54, rear terminal IP20;

Electromagnetic compatibility: meets the IEC60255 series, vibration, impact, and earthquake tests; Insulation withstand voltage of 2kV, impulse withstand voltage of 5kV.

Complete protection function (distinguishing between motor M mode/generator G mode)

The device has two functional levels: Motor motor mode and Generator generator mode. Different protection modules are enabled, and each functional block has a corresponding ANSI equipment number.

🔹 short circuit protection

Three phase non directional overcurrent (51/50): low section, high section, instantaneous; Support multiple inverse time curves.

Directional overcurrent (67): Generator mode is available.

Differential protection (87M/87G)

Diff3: High impedance/flux balanced differential, universal for motors and generators;

Diff6G: Stable three-phase differential, specifically designed for generators.

🔹 Ground fault protection

Non directional grounding overcurrent (51N/50N) low/high/instantaneous;

Directional grounding fault protection (67N);

High impedance limited grounding REF1A (87N, generator);

Remaining overvoltage protection of 59N.

🔹 Overload and unbalance protection

TOL3Dev (49) thermal overload: motor/generator/transformer thermal model, supporting stator and rotor time constants, restart lockout;

Negative sequence overcurrent protection NPS3 (46) reflects three-phase imbalance and phase failure.

🔹 Voltage protection

Overvoltage 59, undervoltage 27, phase sequence voltage protection.

🔹 Frequency protection (generator mode)

Over frequency, under frequency, df/dt frequency slip, up to 5 segments, used for low-frequency load shedding.

🔹 Generator specific protection

Underexcitation protection UE6 (40);

Overexcitation protection OE1 (24) U/f protection;

Reverse power/low power protection UPOW6 (32);

Directional over power OPOW6.

🔹 Motor specific protection

Motor start monitoring MotStart (48/14/66): Monitor start time, locked rotor, allowed start times, restart after start prohibited;

Undercurrent protection NUC3 (37);

Reverse phase protection PREV3 (46R).

🔹 Public Additional Protection and Surveillance

Circuit breaker failure protection CBFP (62BF);

Excitation inrush current detection Inrush 3 (68);

PT fuse failure monitoring FuseFail (60);

Check the same period/no pressure SCVC (25), and connect the generator to the grid for use.

Control and status monitoring functions

Device Control

Up to 2 circuit breakers, 5 isolating switches, and 2 three state isolating switches;

Local/remote control; Complete interval interlocking logic;

The HMI panel allows direct operation of switches.

Equipment status monitoring Condition monitoring

Trip circuit monitoring TCS, detecting disconnection in the tripping and closing circuit;

Circuit breaker electrical wear counting and operation time statistics;

Circuit breaker spring energy storage, SF6 gas pressure monitoring;

Plan maintenance alerts.

Measurement function

Three phase current and voltage, zero sequence quantity, active and reactive power, power factor, bidirectional electrical energy, frequency; External RTD is used to measure the temperature of windings and bearings.

Wave recording

MEDREC16 disturbance recording: up to 16 analog+16 digital channels;

Event SOE record; Run statistical counters.

Software tools and configuration methods

CAP505: Main engineering software, completes protection setting, I/O mapping, and IEC61131-3 PLC logic programming;

Relay Mimic Editor: Edit HMI local dynamic simulation MIMIC screen;

CAP501: Fixed value tool;

LNT505: LON bus network configuration tool;

Debugging interface: Connect the optical RS232 port on the front panel of the device to a computer;

Support switching between multiple fixed value groups and remote modification of fixed values.

PLC programmable logic

Complete functional block library: AND/OR/NOT, timer, pulse timer, RS trigger, comparator, data type conversion, can achieve custom interlocking, alarm, timing; Realize signal exchange between multiple devices through LON bus, reducing secondary hard wiring.

Communication capability

SPA bus: ABB’s old internal bus;

LON bus: focus on achieving peer-to-peer communication between devices and cross interval interlocking logic;

Modbus RTU (supported by REM543);

Hardware interface: Front panel optical RS-232; Backboard X3.2 (SPA/Modbus); X3.3（SPA/LON）； Support fiber optic modules RER103 and RER123 for fiber optic isolation.

Note: The REM54 series does not support IEC61850 or the HART protocol, and cannot be used with DHH805-A handheld devices; Debugging relies on CAP505 software and local HMI.

Order coding rules

Order number example: REM543CM212AAAA Segment meaning:

Model: REM543/REM545;

Functional level: M=motor mode, G=generator mode;

Hardware version number;

Power type;

A/B: A=Normal CT/PT; B=Supports Roche sensors;

Display screen: A fixed local HMI, B external independent display panel.

Typical application wiring example

Directly start asynchronous motor protection;

Starting synchronous motor with autotransformer;

Diesel generator single machine grounding system;

Generator transformer unit protection;

Multiple units in the power plant are connected to the grid for protection.

Key points of technical data

Auxiliary power supply: AC 110-240V, DC24-2220V; Power consumption<50W;

The digital input threshold can be configured; The maximum output contact is 250V AC/DC;

RTD supports Pt100, Pt1000, Ni, Cu copper resistors;

Environment: Working -10 ℃~+55 ℃, Storage -40~+70 ℃;

Event recording and waveform recording will not be lost in case of power failure.