K-WANG

+086-15305925923
Service expert in industrial control field！
English 简体中文
Product
Article
NameDescriptionContent
Adequate Inventory, Timely Service
pursuit of excellence 
Ship control system
Equipment control system
Power monitoring system
Current position:
Home >> ABB >> ABB REX 521 protective relay
新闻动态
newS
   
Brand

ABB REX 521 protective relay

From: | Author:Wang | Time :2025-05-20 | 350 visit: | 🔊 Click to read aloud ❚❚ ▶ | Share:

ABB REX 521 protective relay

Product positioning and hardware configuration

REX 521 is a multifunctional protective relay that supports multiple hardware versions (Basic/Medium/High/Sensor) and standard configurations (such as B01/B02/M01/H01, etc.), suitable for different voltage levels and protection requirements.

Hardware differences:

Basic: Basic type, supports basic overcurrent and ground fault protection, with fewer digital inputs/outputs.

Medium: Enhanced, extended digital input/output, supports directional protection and automatic reclosing.

High/Sensor: A high-end model that integrates advanced functions such as sensor interfaces, voltage/frequency protection, and motor start monitoring.

Key components:

Built in current/voltage transformer interface, supporting 1A/5A current and 100V voltage input.

Provide digital input/output, communication ports (RS-232/RS-485), and optional fiber optic modules, supporting protocols such as Modbus and DNP 3.0.


Core functions and protective features

1. Protection function

Overcurrent protection:

Supports three-phase overcurrent (3I>, 3I>>, 3I>>>) and ground fault (Io>, Io>>, Io>>>), including directional (67N) and non directional configurations, supporting definite time (DT) and inverse time (IDMT) characteristics.

Built in harmonic suppression and excitation inrush current detection (3I2f>) to avoid misoperation.

Voltage and frequency protection:

Overvoltage/undervoltage protection (3U>, 3U<<), residual voltage protection (Uo>), frequency anomaly protection (f1/f2), supporting voltage imbalance and phase sequence protection (U1U2<>_1).

Motor and transformer protection:

Motor start-up monitoring (Is2t n<), thermal overload protection (3Ithdev>), phase sequence reversal protection (3I()), fuse fault detection (FUSEF).

Automatic reclosing (O ->I):

Supports up to 5 reclosures, can be triggered by protection start or trip signals, and has dead time and discrimination time settings.

2. Measurement and monitoring

Electrical quantity measurement:

Real time measurement of three-phase current/voltage, power, frequency, and energy, supporting true RMS and fundamental wave analysis.

The disturbance recorder (DREC) can capture fault waveforms and supports manual or triggered recording.

Status monitoring:

Circuit breaker wear monitoring (CB wear1), trip circuit supervision (TCS1), power input supervision (MCS 3I/3U).

Power quality monitoring (PQ 3Inf/PQ 3Unf), supporting harmonic analysis and THD/TDD calculations.

3. Communication and Control

Protocol support:

Standard SPA, Modbus RTU/ASCII, DNP 3.0, optional IEC 61850 adapter (requires expansion module).


Remote control:

Support local/remote switching (I<->O POS), circuit breaker opening and closing control (I<->O CB1), and integrated interlocking logic.

3、 Standard configuration and application scenarios

1. Basic Configuration (Basic: B01/B02)

Function: Non directional overcurrent/ground fault protection, thermal overload protection, B02 supports automatic reclosing.

Application: Single busbar system for outgoing or incoming line protection, suitable for resistance grounding or solid grounded networks.

2. Intermediate configuration (Medium: M01/M02)

Function: Add directional grounding fault protection (67N), phase sequence protection, M02 supports reclosing and angle control (BACTRL).

Application: Compensate for grounding or isolated networks, requiring selective protection for outgoing scenarios.


  • Rolls-Royce R10I53S 98H0101A0000I Marine Panel Computer for Ship Automation and Integrated Vessel Control Systems
  • Woodward 8406-121 - EGCP-2 / EGCP - 2 Digital Control REV G
  • Woodward 8440-1019 A - SPM-D10/SPM-D Sync Controller synchronizing system
  • Woodward 5466-318 - MicroNet TMR Kernel P.S Module
  • Woodward 8270-1060 - SPEED CONTROLLER REV.D DYN1-10504-004-0-24 FINAL ASSY
  • Woodward 8440-1884 - EASYGEN-2500-5/P1 Genset Controller Rev. A WITHOUT ACCS
  • Woodward 9907-018 - LOW VOLTAGE 2301A LOAD SHARING AND SPEED CONTROL REV.H
  • Woodward 8440-2028 - DIGITAL I/O EXPANSION MODULE REV. NEW IKD1 IKD1M WITH CD
  • Woodward 5431-640 C - Dual Dynamics 1000 Series Speed Control Module
  • Woodward MFR2S45B/EVC1 - CONTROLLER RL20710
  • Woodward 8237-2600 - TURBINE CONTROL PANEL PROTECH GII, 8200-1302
  • Woodward 9907-838 - LOAD SHARING MODULE REV NEW
  • Woodward 8272-582 - APM MOTOR CONTROL 110-220V AC/DC
  • Woodward 5460-570 - SPEED REFERENCE MODULE
  • Woodward 8440-1041 - CONTROL MODULE
  • Woodward 5466-5026 - MICRONET SIMPLEX HIGH DENSITY ANALOG MODULE
  • Woodward 5441-693 - DIGITAL I/O MODULE
  • Woodward 9905-214 - 701 DIGITAL SPEED CONTROL REV J
  • Woodward 8273-1013 - 2301E-ST LOAD SHARING & SPEED CONTROL REV NEW
  • Woodward 9907-018 - 2301a / 2301A Low Voltage Load Sharing AND Speed Control REV.E
  • Woodward MRU4A0AB - HIGH PROTEC VOLTAGE PROTECTION RELAY REV:Y
  • Woodward DPG 2201-002 - Speed Governor (DPG-2201-002)
  • Woodward DYNT 17200 - MAGNETIC PICKUP SENSOR 3/8 07-16
  • Woodward 8440-2028 - IKD1M Digital I/O Expansion Module REV :NEW
  • Woodward 9907-018 - 2301A Load Sharing & Speed Control Rev: H Low Voltage
  • Woodward 8440-1884 - GENSET CONTROLLER EASYGEN-2500-5/P1 REV: K
  • Woodward 9907-173 - Module Load Sharing 120 Volt REV B
  • Woodward APECS MODEL 4500 - PROGRAMMABLE ENGINE CONTROL
  • Woodward 8406-121 - egcp-2 digital control
  • Woodward 8402-214 - SOGAV105 VALVE (24V) GAS METERING WITH 5852-130 800 N SOLENOID
  • Woodward 8440-1041 G - EXPANSION BOARD IKD1
  • Woodward 8444-1104 - MFR300 MULTI FUNCTION RELAY
  • Woodward LS-5 - Motherboard Synchronization Load Distribution Controller
  • Woodward 5460-571 A - SPEED SENSOR MODULE
  • Woodward 8272-582 - APM Motor Control 100-220V AC/DC
  • Woodward 8440-1614 - GCP-32 Genset Control Package REV:H
  • Woodward NC3116 - SEG GENERATOR CONTROLLLER 16463777
  • Woodward 9907-014 - 2301A SPEED CONTROL REV H
  • Woodward 8272-582 - APM MOTOR CONTROL
  • Woodward 8270-1060 - SPEED CONTROLLER REV.C DYN1-10504-004-0-24 FINAL ASSY
  • Woodward 8444-1074A - lsg / LSG Load Share Gateway Transducer Rev: LSG
  • Woodward 9907-018 - LOW VOLTAGE 2301A LOAD SHARING AND SPEED CONTROL REV.E
  • Woodward 8290-189 - Speed Controller Rev. U
  • Woodward 8290-189 - Speed Controller Rev. V
  • Woodward 8272-583 - APM Motor Control 24vdc
  • Woodward 8404-2006 - Lseries ITB 30m Actuator with Position Control logic
  • Woodward 8516-050 - 2400 RPM CW DRIVE SHAFT ROTATION MOTOR
  • Woodward 9905-016 B - Process Control Unit
  • Woodward 5484-721 - motor
  • Woodward 5501-470D - NETCON CPU_040 W/O LL MEMORY Rev A
  • Woodward 3522-1004 - BUM60-1224-54-B-001 EM- DRIVER BUM60-VC-A0-0093
  • Woodward 9907-019 - LOW VOLTAGE 2301A LOAD SHARING & SPEED CONTROL REV.H
  • Woodward 9907-018 - 2301A LOAD SHARING AND SPEED CONTROL REV.H
  • Woodward 8256-021 - EPG Rotary Actuator Model 524
  • Woodward 8446-1048 - EASYGEN RP-3000 ANNUNCIATOR REV:H HMI
  • Woodward 5501-471C - NetCon SIO Module Rev A
  • Woodward 8273-140 - 2301D LOAD SHARING AND SPEED CONTROL UNIT REV.A
  • Woodward 9905-211 - 701 DIGITAL SPEED CONTROL REV.J
  • Woodward 8272 64 - Motorized Potentiometer (MOP)
  • Woodward 9907-173 - Load Sharing Module 120V
  • Woodward 9905-797 - Digital Syncronizer
  • Woodward 8272-685 Rev L - Digital Reference Unit BRAND NEW IN BOX-
  • Woodward 8444-1081 - UMT1 Control Module 2751) [ ]
  • Woodward 9906-226 - 721 Digital Control 18W NEW LISTING
  • Woodward 8272-518 - Motor Control 110VDC Input Woodward P/N 8272 518
  • Woodward 8521-367 - UG-8 Governor P/N R R.P.M 750-1280 / UG8
  • Woodward 9907-019 Rev New 9703 - Low Voltage 2301A Load Sharing & Speed Control
  • Woodward 2001-12E2U1B1S1A 2000-4505 - FUEL SHUTOFF STOP SOLENOID VALVE
  • Woodward Easygen-2500-5 - GENSET CONTROLLER - FOR PART
  • Woodward 2001-12E2U1B1S1A 2000-4505 - FUEL SHUTOFF STOP SOLENOID VALVE
  • Woodward 9907-018 - 2301A speed control board
  • Group 8272-583 - Apm Motor Control DC24V
  • Woodward 8272-583 - Amp Motor Control DC24V
  • Woodward DPG-2201-002 - Digital Controller Revision New
  • Woodward 8440-1884K REV,K - GENERATOR CONTROLLER EASYGEN-2500-5
  • Woodward 8272-824 REV.C - LVDT SIGNAL CONDITIONER
  • Woodward 8272-582 - APM Motor Control
  • Woodward 9907-838 - LOAD SHARING MODULE REV. NEW
  • Woodward SA-4478 - EPS1000 Speed Switch
  • Woodward z 21 - governor motor rpm 1350
  • Woodward 5418-151 - Computer Assy : for Woodward 8273-256 Atlas Controller
  • Woodward 8272-517 - Pm Electric Motor
  • Woodward 5448-914 - GCP-20 Genset Controller GCP-20 REV D P/N:
  • Woodward 8440-1884 Rev J E231544 - Easy Gen 2000 Genset Controller
  • Woodward 5501-471 REV B - NETCON 5000B SIO W/SCREW POSTS
  • Woodward 8440-2512 REV B - LS-5 CIRCUIT BREAKER CONTROL PROTECTION LS-511-5/P1
  • Woodward 5466-256J REV F - Discrete I/O Module PCB
  • Woodward 8290-048 Rev. F - Generator Load Sensor 8290048
  • Woodward 9906-619 REV A - 723 PLUS DIGITAL CONTROL
  • Woodward 8440-1832 - GCP-31 NATIONAL OILWELL VARCO
  • Woodward 5466-031 REV H - NETCON IO CONTROLLER
  • Woodward ProTech 203 - Overspeed Protection System, For Parts/Repair
  • Woodward 8404-1006 - Control Module
  • Woodward 8444-1002 REV G - UMT1 MEASURING TRANSDUCERS
  • Woodward 8440-2151 REV:A - LS-522-5/P1 HMI DISPLAY [BRAND NEW ]
  • Woodward 8270-274k - Pamp Generator
  • Woodward 9907-028 REV E - SPM-A SYNCHRONIZER MODULE
  • Woodward XRW1-47 / XRW147 - 1pc XRW147 XRW1-47
  • Woodward 8440-2050 J REV - EASYGEN-3200-5 GENSET CONTROLLER (TESTED FAST SHIP)
  • Woodward 8406-011 REV.AC - GEN PART 6000 24V DC CONTROLLER - W/O ANY ACCS.
  • Woodward 8444-1019 E - Measuring Transducer WOODWARD UMT 1
  • Woodward 9907-166 Rev R - 505 Turbine Control Operator Panel New
  • Woodward 5501-471 - Actuator Driver Module, 4 Channel, (UPP)
  • Woodward 5484-875 - PM MOTOR 24VDC 5 RPM
  • Woodward 8405-062 - Actuator
  • Woodward smm40 - speed adjusting motor
  • Woodward DPG-2201-002 REV D - DIGITAL CONTROLLER NEW LISTING
  • Woodward 5484-875 - PM MOTOR 24 VDC 5 RPM
  • Woodward 5437-845 - board-notch filter 3khz
  • Woodward BL20400 - 3X400 VAC Battery Charger
  • Woodward 8800 - 1001 Rev-C - DSS-2, 2 Channel Digital Speed Switch I/N:
  • Woodward 9905-971 Rev J - Linknet 16 Channel Discrete Input Module 18-32VDC 14.2W
  • Woodward 5501-224 revC - Control Board
  • Woodward 8901-037 - Booster Servo Motor
  • Woodward 1767-367 S/N: 0920702 - Z21 WK GOVERNOR MOTOR 2700 RPM KM 58-20 K 230V
  • Woodward CSC3SUWA REV K - CSC3SUWA Controller
  • Woodward 8272-583 - APM MOTOR CONTROL
  • Woodward 5437 18 Rev.A - module netcon derivative analog
  • Woodward 5448-885 REV F - MFR1 MULTI FUNCTION RELAY
  • Woodward 8273-456 REV.A - ATLAS W/O PC104 MODULE
  • Woodward 9905-377 - 2301A Load Sharing and Speed Control
  • Woodward 5466-031 REV. C - Netcon Control Module
  • Woodward 8270-007 - Load Signal Control
  • Woodward 8440-1884 C - Controller Easygen 2500-5
  • Woodward 8270-975 REV.G - 2301 AMPLIFIER MODULE
  • Woodward 1766-463 - Governor Speed Adjusting Motor 24 VDC
  • Woodward 9907-162 Rev:F - 505 Turbine Controller
  • Woodward 9907-838 - Speed control