SEL-487B Bus Differential and Breaker Failure Relay

ProtectionProtect bus systems with up to 21 terminals (21 CTs per relay, 63 CTs with a three-relay scheme), 6 protection zones, and 3 additional independent check zones. To optimize protection security, the check zones supervise up to 6 zones, and a patented open CT detection algorithm blocks potential misoperations during open or shorted CT conditions. Differential and directional current elements provide increased security and fast fault detection. Reduce protection costs with built-in breaker failure protection.

FlexibilityImplement different ratio CTs and nondedicated CTs with the SEL-487B Bus Differential and Breaker Failure Relay. Eliminate complex wiring by using CT ratios that differ by up to a factor of 10:1. Take advantage of the same CTs for differential protection, metering, backup relaying, and other functions.

Making Electric Power Safer, More Reliable, and More Economical ®

A Powerful Solution for Busbar Differential Protection

Select the SEL-487B for the differential protection of busbar systems with up to 21 terminals.

Automation and ControlReduce project costs and simplify interconnect wiring using multiple communications protocols and ports. Configurable operator controls and simplified variable naming provide added power to SELogic

® control equations.

Monitoring and MeteringProvide accurate, timely monitoring and metering of busbar, feeder, and substation signals. Terminal currents, breaker and disconnect positions, station dc voltage levels, and three-phase voltage are continuously monitored and updated.

Enhanced SecurityIndicate the relay configuration, who accesses it, and at what access level, with programmable alarm bits.

Features and Benefits

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Apply SEL-487B Relays with Ethernet directly to a local network or through an SEL communications processor.

• Use DNP3 LAN/WAN or Modbus® TCP to quickly send information through your networks.

• Provide information to the right people for improved system performance.

• Transfer data with high-speed Ethernet for fast HMI updates and file uploads.

• Use popular Telnet applications for easy terminal communication with SEL relays and other devices.

• Combine IEC 61850 technology, an Ethernet network, and the SEL-487B for the fastest overall performance of IEC 61850 relays for substation automation and control. SEL-2725

SEL-3351

SEL-487B

Network

SEL-351

SEL-351

SEL-351

SEL-3530

• Access basic relay information on a standard Ethernet network with the built-in web server. View relay status, Sequential Events Recorder (SER) reports, metering information, and settings. Web server access requires the relay password and is limited to read-only viewing of information.

• Simplify wiring and installation by receiving a time signal over existing Ethernet networks. SNTP makes a good backup to more accurate IRIG-B time synchronization.

Typical Ethernet network configuration.

Functional Overview

Integrate With Ethernet Networks

Access Security

EIA-232 Ethernet*(Copper or Fiber-Optic)

16 CSE

4 2

IRIG-B

1

HMI

OperatorInterface

SEL MIRRORED BITS®

85RIORTU

RemoteTerminal Unit

MET

High-AccuracyMetering

DFR

Event Reports

SBM

StationBattery Monitor

SER

SequentialEvents Recorder

LGC

ExpandedSELOGIC®

*Optional Functions

52-6

3

–50

0

50

100

–150

0

–100

–50

0

50

Cur

rent

(am

pere

s)

(No Differential Element Operation)

IO1

IO2

Internal Fault Detection

Cur

rent

(am

pere

s)

0

5

–5

0

0

5

10

15

20

Fault Inception

Internal Fault Detection (<1 cycle)

IO1

IO2

External faults are detected by directional elements within the relay. When an external fault is detected, the relay enters a high-security mode and dynamically selects a higher slope for the differential elements, making them more secure during the fault.

The SEL-487B includes six independent current differential elements, and each one provides:

• Fast operate times for all busbar faults

• Security for external faults with heavy CT saturation

• Security with subsidence current present

• High sensitivity to busbar faults

• Minimum delay for faults evolving from external to internal

Differential element remains secure for external faults with CT saturation.

CT SupervisionFor each zone, sensitive current differential elements detect differential current resulting from a differential element that is not well balanced (i.e., wrong CT ratios). If the conditions persist for longer than a user-specified delay, the element alarms and can be used to generate an external alarm and/or block the zone.

Voltage ElementSupervise current differential tripping within the relay using voltage elements. Three separate voltage elements consist of two levels of phase under- and overvoltage elements and two levels of negative- and zero-sequence overvoltage elements for each of the three analog voltage quantities measured.

Overcurrent ElementsChoose from ten overcurrent curves for each current input. Each torque-controlled, time-overcurrent element has two reset characteristics. There is also one level of instantaneous and definite-time elements available for each current input.

Differential element operation in less than one cycle for internal faults, including high-speed contact closure.

Fault Detection Logic

Differential Element

Trip Output

Internal Fault

External Fault

CT Supervision

Slope 1 Slope 2

CurrentInput I01

CurrentInput I18

IOP

IRT

High-Security Operate Slope

Standard Operate Slope

Restraint Zone

Time

Time

Differential Protection

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differential elements, even for complex bus arrangements as shown (Figure A).

Note that the SEL-487B automatically includes the Zone 4 currents in Zone 3 when Disconnect Switch DS3 is closed (Figure B).

The SEL-487B includes complete breaker failure protection, including retrip, for each terminal. Internal breaker failure is determined by predefined protection schemes that allow different types of trip signals and current flow conditions. External breaker failure device inputs can be substituted for the internal breaker failure schemes, while providing individual or identical responses to each breaker failure condition.

The SEL-487B dynamically assigns the input currents to the correct differential elements without the need for additional auxiliary relays. Connect the digital inputs from the busbar disconnect and breaker auxiliary contacts directly to the relay. SELogic control equations and zone selection logic will correctly assign the currents to the

Breaker Failure Detection

Dynamic Zone Configuration

Open-Phase Detection

Open-PhaseDetection

High-speed, open-pole detection logic detects open-pole conditions in fewer than 0.75 cycles to reduce breaker failure coordination times.

Figure A.

Figure B.

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The patented open CT detection logic improves the security of the current differential element. It assures current differential bus zones will not misoperate due to terminals that cannot be properly measured. This advanced logic, when implemented, will block differential element misoperations that occur under open or shorted CT conditions. The CT detection logic monitors the CT terminals in every bus zone to detect when a contributing CT has failed.

In complex busbar layouts, the SEL-487B uses disconnect auxiliary contact status to define current differential bus zones and supervises these zones with the independent “check zone” feature to prevent misoperation due to discrepancy.

Check Zone Key Features• Provides secure supervision for bus zones

• Supervises bus zones independently of terminal auxiliary disconnect status

• Processes its logic independently of all bus zones

• Fits a wide variety of applications and protection philosophies, with independent pickup and slope settings

Three-Relay Bus Protection Application—For Up to 21 TerminalsThree independent check zones are provided per relay.

Configure a check zone for every phase, encompassing all terminals at the station (except bus coupler and sectionalizing breakers), independent of disconnect auxiliary contact status.

acSELErator QuickSet® SEL-5030 Develop SEL-487B settings and busbar configurations offline with acSELErator QuickSet. The system automatically checks interrelated settings and highlights out-of-range settings. Settings created offline can be transferred to the SEL-487B by using a PC communications link.

Graphical Logic Editor (GLE) Simplify the process of configuring your SEL-487B using the GLE in acSELErator QuickSet SEL-5030 Software. The GLE allows you to view your SELogic equations graphically, so your settings files can be documented for easier validation and commissioning. Convert existing SELogic control equations to easy-to-read diagrams, and save diagrams with your QuickSet settings.

Advanced Open CT Detection Logic

Three Independent Check Zones Supervise Up to Six Differential Bus Zones

acSELErator® Software

52

52

52

TR 1 TR 2

52

FD 1

52

FD 2

Zone 1 Zone 2 Check Zone

2 enoZ1 enoZ

52

FD 3

Check Zone

SEL-487B

3

33

33

3

3

This is a basic example of a check zone supervising only two three-phase zones, with one SEL-487B per phase.

acSELErator® graphical logic editor (GLE).

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The SEL-487B control logic can replace the following:

• Traditional panel control switches

• RTU-to-relay wiring

• Traditional latching relays

• Traditional indicating panel lights

• Panel meters

Eliminate traditional panel control switches with 32 local control points. Set, clear, or pulse local control points with the programmable front-panel pushbuttons and display. Program the local control points to implement your control scheme via SELogic control equations.

Eliminate RTU-to-relay wiring with 32 remote control points. Set, clear, or pulse remote control points via serial port commands. Incorporate the remote control points into your control scheme via SELogic control equations. Apply remote control points for SCADA-type control operations, such as trip and group selection.

Automation and Control

Advanced Display and Controls for Next-Generation Substation Automation and Integration

Detailed, programmable target LEDs with user-configurable labels give fast and simple information to assist dispatchers and line crews in rapidly restoring power. Optionally, add eight tricolored target LEDs.

Easy-to-use keypad aids simple navigation and set-point adjustment.

Rotating display automatically scrolls between custom metering displays, alarms, event summaries, and preconfigured fundamental line quantity displays.

Breaker status indication.

Service control switch.

Programmable operator pushbuttons and configurable labels provide local switches to replace traditional panel switches. Optionally, add four tricolored operator pushbuttons to control even more circuit breakers.

The front-panel LCD shows the latest 200 of the 1,000 events time-stamped in the Sequential Events Recorder (SER).

Enhanced Front-Panel HMI

Improve efficiency and simplify installation with more target LEDs and operator buttons. The 7U and 9U chassis have options for an additional eight target LEDs and four operator control buttons.

• Indicate relay state and various trip conditions with 24 target LEDs, or configure the LEDs for specific applications.

• Meet operator control needs by modifying the 12 operator buttons to replace traditional panel switches, and control more circuit breakers.

SEL provides a worldwide, ten-year product warranty and —40° to +85°C operating temperature range—the best in the industry.

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Access Useful Information• Metering quantities include primary and secondary voltage

and current magnitudes, and angles for each terminal.

• Zone information displays primary or secondary current and voltage for each terminal. The polarity of each CT and the bus zones in each of the protective zones at the station are also included.

• Differential metering shows the operating and restraint currents for each zone as well as the reference current.

• Battery monitoring provides warning and alarm thresholds that can be monitored with the SEL-2032 Communications Processor and the SEL-3530 Real-Time Automation Controller (RTAC). Trigger messages via local display, telephone, pager, or other devices.

Simplify System Testing and Post-Fault AnalysisThe SEL-487B event-reporting capabilities help improve understanding of even the most complex protective scheme operations. Eliminate external recorder and metering requirements with oscillographic and binary COMTRADE event reports and SER.

SERGain a broad perspective of relay element operation with the SER in the SEL-487B. Items that trigger an SER entry are selectable and can include as many as 250 monitoring points, such as input/output, change of state, element pickup/dropout, and more. The relay SER stores the latest 1,000 events, which are available through the SER command. The latest 200 events are also viewable via the front-panel LCD.

Monitoring and Metering

Illustrated here is security during an external fault with CT saturation. The SEL-487B stores up to 480 cycles (8 seconds), in either 15-, 30-, 60-, or 120-cycle event reports, at 24 samples per cycle in nonvolatile memory. Relay settings are appended to the end of each report.

Illustrated here is security during MOV arrester conduction. User-selected internal or external triggers can be used to generate oscillographic event reports that include voltage, current, and element status information.

acSELErator Analytic Assistant® SEL-5601 Software helps you compare event reports from multiple relays, enhancing this powerful tool’s analytic capabilities.

Metering AccuracyAll metering accuracies are based on an ambient temperature of 20°C and nominal frequency.

Instantaneous differential metering per zone (steady state)

IOP, IRT ±5.0%, ±0.02 • INOM

Per-phase instantaneous metering (steady state)

V01, V02, and V03 >30 V ±1% I01, I02, . . ., I21 ±3% ±0.004 • INOM , ±2.0°

Conformal Coating OptionProtect equipment from harsh environments and airborne contaminants, such as hydrogen sulfide, chlorine, salt, and moisture.

Chassis Options9U chassis supports up to 4 optional I/O boards

7U chassis supports up to 2 optional I/O boards

Event ReportsVolatile memory 5 seconds of back-to-back event

reports sampled at 8 kHz

Nonvolatile memory At least 5 event reports of a 3-second duration sampled at 8 kHz

Resolution 4- and 12-samples/cycle

Event SummaryStorage 100 summaries

Sequential Events RecorderSequential Events Recorder storage 1000 entries

Trigger elements 250 monitoring points Processing rate 12 samples per cycle

AC Voltage Inputs (3 total)300 V continuous across the terminals

(connect any voltage up to 300 Vac)

600 Vac for 10 seconds

Burden ≤0.5 VA @ 5 A

AC Current Inputs (21 total)5 A nominal

15 A continuous, 500 A for 1 second, linear to 100 A symmetrical 500 A for 1 second, 1250 A for 1 cycle

Burden ≤0.5 VA @ 5 A

1 A nominal 3 A continuous, 100 A for 1 second, linear to 20 A symmetrical 100 A for 1 second, 250 A for 1 cycle

Burden ≤0.1 VA @ 1 A

Power Supply Ratings125/250 Vdc or 120/230 Vac

Range 85—300 Vdc or 85—264 Vac

48/125 Vdc or 120 Vac Range 38—140 Vdc or 85—140 Vac

24/48 Vdc Range 18—60 Vdc

Station DC Battery System Monitor SpecificationsOperating range 0—350 Vdc

Input sampling rate 2 kHz

Processing rate 1/6 cycle

Maximum operating time ≤1.5 seconds (element DC1R) ≤1.5 cycles (all elements but DC1R)

Setting Range DC settings OFF, 15—300 Vdc, 1 Vdc steps

AC ripple setting 1—300 Vac, 1 Vac steps

Accuracy Pickup accuracy ±10%, ±2 Vdc (DC1RP) ±3%, ±2 Vdc (all elements but DC1RP)

Serial Communications PortsThree rear-panel and one front-panel EIA-232 ports

SEL ASCII commands; SEL Fast Messages; DNP3

Serial data speed 300—57600 bps

Ethernet Communications OptionsProvides IEC 61850, DNP3 LAN/WAN, FTP, Telnet protocols, and web server capabilities

Ethernet connection media options:

10/100BASE-T twisted-pair network

10/100BASE-FX fiber-optic network

General Specifications

Relay provides many I/O port options (9U version shown).

Pullman, Washington USATel: +1.509.332.1890 • Fax: +1.509.332.7990 • www.selinc.com • info@selinc.com

© 2005—2012 by Schweitzer Engineering Laboratories, Inc. PF00063 • 20120621

SEL-487B Bus Differential and Breaker Failure Relay