Schweitzer Engineering Laboratories SEL-351 User manual

SEL-351
DIRECTIONAL OVERCURRENT RELAY
RECLOSING RELAY
FAULT LOCATOR
INSTRUCTION MANUAL
SCHWEITZER ENGINEERING LABORATORIES
2350 NE HOPKINS COURT
PULLMAN, WA USA 99163-5603
TEL: [phone] FAX: [phone]
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The software (firmware), schematic drawings, relay commands, and relay messages are copyright protected by the United States Copyright Law and International
Treaty provisions. All rights are reserved.
You may not copy, alter, disassemble, or reverse-engineer the software. You may not provide the software to any third party.
All brand or product names appearing in this document are the trademark or registered trademark of their respective holders.
Schweitzer Engineering Laboratories, SELOGIC, Connectorized, Job Done and are registered trademarks of Schweitzer Engineering Laboratories.
The English language manual is the only approved SEL manual.
Copyright © SEL 1997, 1998, 1999, 2000 (All rights reserved) Printed in USA.
This product is covered by U.S. Patent Numbers: 5,041,737; 5,208,545; 5,317,472; 5,349,490; 5,365,396; 5,367,426; 5,479,315; 5,515,227; 5,602,707; 5,652,688;
5,694,281; 5,790,418; 5,793,750; 5,883,578 U.S. Patent(s) Pending, and Foreign Patent(s) Issued and Pending.
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Date Code 20001006 Manual Change Information i
SEL-351 Instruction Manual
MANUAL CHANGE INFORMATION
The date code at the bottom of each page of this manual reflects the creation or revision date. Date
codes are changed only on pages that have been revised and any following pages affected by the
revisions (i.e., pagination). If significant revisions are made to a section, the date code on all pages
of the section will be changed to reflect the revision date.
Each time revisions are made, both the main table of contents and the affected individual section
table of contents are regenerated and the date code is changed to reflect the revision date.
Changes in this manual to date are summarized below (most recent revisions listed at top).
Revision
Date Summary of Revisions
The Manual Change Information section has been created to begin a record of revisions to this
manual. All changes will be recorded in this Summary of Revisions table.
20001006 This revision includes the following changes:
Section 1:
− Corrected phase angle accuracy of synchronism check elements.
Section 2:
− Updated Figure 2.1 and accompanying text.
− Added cable for SEL-DTA2 to Table 2.1.
− Added note to Table 2.7 (Fast Operate).
Section 3:
− Corrected setting range for 59Q in Table 3.8.
− Added SYNCP angle setting option for delta-connected voltage relays.
− Clarified synchronism check logic description.
− Expanded setting range for 27B81P in Table 3.11.
Section 4:
− Added !LOP to 51PTC setting in the Apply Load-Encroachment Logic to the
Phase Time-Overcurrent subsection.
Section 5:
− Added explanation to the Target Reset/Lamp Test Front-Panel Pushbutton
subsection to indicate that the targets cannot be reset when a TRIP condition is
still present.
Section 6:
− Corrected 79DTL factory default setting in Table 6.4.
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ii Manual Change Information Date Code 20001006
SEL-351 Instruction Manual
Revision
Date Summary of Revisions
Section 7:
− Added Details on the Remote Control Switch MOMENTARY Position
subsection.
− Clarified the operation of the latch control switches when the SEL-351 Relay
loses power (see the Latch Control Switches subsection).
− Corrected subsection Relay Disabled Momentarily During Active Setting
Group Change.
Section 8:
− Added qualifying statement about changing the LDAR setting.
Section 9:
− Corrected error in the Relay Word bit description for 51G in Table 9.4.
− Added SYNCP angle setting option for delta-connected voltages to Settings
Sheet 9.
− Expanded setting range for 27B81P on Settings Sheet 9.
− Added description of RTSCTS = MBT setting choice to the Port Settings
Sheet.
− Added AUTO = DTA setting choice to the Port Settings Sheet.
Section 10:
− Added DTA2 compatibility information.
− Added notes about powering down the relay after setting the date or time.
− Corrected HIS command information.
− Corrected TAR n K command description.
− Added note to TAR R command description.
− Added details to COP command description.
− Added VER Command (Show Relay Configuration and Firmware Version).
− Revised SEL-351 Command Summary.
Section 11:
− Corrected Rotating Default Display example.
Section 12:
− Added Table 12.1.
− Added cautionary note on SER settings.
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Date Code 20001006 Manual Change Information iii
SEL-351 Instruction Manual
Revision
Date Summary of Revisions
Appendix A:
− Updated Firmware Version information.
Appendix B:
− Added information to Step 16 in the Upgrade Procedure for Breaker Wear
Monitor data.
Appendix D:
− Updated ASCII Fast Meter Configuration Block.
− Updated ID Message.
− Updated CAS Message.
Appendix G:
− Revised Figure G.1 and Figure G.2.
− Updated Table G.2.
Appendix H:
− Corrected spelling of DECPLA, DECPLV, and DECPLM settings for DNP.
Appendix I:
−− Added MIRRORED BITS SET P Settings Sheet.
20000424 This revision includes the following literature changes (no firmware changes):
Section 4:
− Updated documentation to reflect the corrected loss-of-potential V1unlatch
threshold (already incorporated in firmware revisions R111 and R205.).
Appendix A:
− Corrected Firmware Version information page to add the loss-of-potential V1
unlatch threshold changes previously updated in firmware revisions R111 and
R205.
991123 This revision includes the following changes:
Appendix H:
− Corrected documentation errors in DNP 3.0 Device Profile, page H-5.
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iv Manual Change Information Date Code 20001006
SEL-351 Instruction Manual
Revision
Date Summary of Revisions
990827 This revision includes the following changes:
Updated MIRRORED BITS™ format throughout to reflect new trademark.
Section 3:
− Added explanation to the Synchronism Check Elements subsection for the new
angle setting option for the SYNCP (synchronizing phase) setting.
Synchronism check can now be accomplished for synchronism check voltage
input VS connected phase-to-phase or beyond a delta-wye transformer. Setting
SYNCP accounts for the constant angle difference between reference voltage
VA and synchronism check voltage input VS.
Section 9:
− Expanded the setting range for the SYNCP (synchronizing phase) setting to
accommodate compensation angle settings for synchronism check (Settings
Sheet 9 of 24).
− Added the MB8A and MB8B serial port protocol settings options for
MIRRORED BITS protocol operating on communication channels requiring an
eight bit data format (Settings Sheet 24 of 24).
Appendix A:
− Updated Firmware Version information.
Appendix B:
− Updated Firmware Upgrade Instructions.
Appendix H:
− Updated screen capture on page H-14.
Appendix I:
− Explained the MB8A and MB8B serial port protocol settings options for
MIRRORED BITS protocol operating on communication channels requiring an
eight data bit format.
990511 This revision includes the following changes:
Incorporated the following changes into Table 9.10 in Section 9: Setting the
Relay.
− Added Relay Word bit rows (36) and (44) for models 0351x0, 0351x1, and
0351xY.
− Changed INT3P to INB in Relay Word Bit row 48 (52).
− Inserted * as necessary throughout table to indicate unused Relay Word bits.
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Date Code 20001006 Manual Change Information v
SEL-351 Instruction Manual
Revision
Date Summary of Revisions
990224 This revision includes the following changes:
Replaced Section 1: Introduction and Specifications:
− Updated information concerning new model numbers throughout.
− Added new Figure 1.4; all following figures renumbered.
− Updated information in Output Contacts subsection in General Specifications.
Section 2:
− Replaced Circuit Board Jumpers and Battery with Circuit Board
Connections and updated information within that subsection.
− Added new Figure 2.17; updated and renumbered original Figure 2.17.
− Updated information in Table 2.2 and Table 2.8.
− Updated information in the Clock Battery subsection.
Section 7:
− Updated Figure 7.28 and Figure 7.30.
Section 9:
− Updated Settings Sheets to reflect new model numbers; other minor
corrections.
Section 10:
− Updated Table 10.1,Table 10.2, and Table 10.3.
Section 11:
− Updated all diagrams in the Rotating Default Display subsection.
990106 This revision includes the following changes:
−− Added 110 Vdc optional input level to Optoisolated Input Ratings in
Section 1: Introduction and Specifications
− Added 110 V nominal battery voltage to Section 8: Breaker Monitor,
Metering, and Load Profile Functions
981130 This revision includes the following changes:
− SELOGIC®Control Equation torque control settings can no longer be set
directly to logical 0, as explained in the overcurrent element sections of Section
3: Overcurrent, Voltage, Synchronism Check, Frequency, and Power
Elements and the SELOGIC Control Equations settings sheets in the back of
Section 9: Setting the Relay.
− SELOGIC Control Equations drive-to-lockout setting 79DTL has a 60-cycle
dropout time, as explained in Section 6: Close and Reclose Logic.
− SELOGIC Control Equations settings limitations explained in Table G.2 in
Appendix G: Setting SELOGIC Control Equations.
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vi Manual Change Information Date Code 20001006
SEL-351 Instruction Manual
Revision
Date Summary of Revisions
981021 This revision includes the following changes:
− New factory default SELOGIC®Control Equation setting 79RIS = 52A + 79CY
(reclose initiate supervision) explained in Section 6: Close and Reclose Logic.
− SELOGIC Control Equation setting FAULT now momentarily suspends demand
metering updating and peak recording as explained in Section 8: Breaker
Monitor, Metering, and Load Profile Functions.
− Changed entry “Obj. 50, Var. 1, Time and Date” in Table H.2 in Appendix H:
Distributed Network Protocol (DNP) V3.00.
980915 This revision includes the following changes:
− Updated Appendix A: Firmware Versions.
980820 This revision includes the following changes:
− Added Voltage Sag/Swell/Interruption elements to Section 3: Overcurrent,
Voltage, Synchronism Check, Frequency, and Power Elements.
− Updated Relay Word and Explanations in Section9: Setting the Relay.
− Added SSI command to Section 10: Serial Power Communications and
Commands.
−− Updated Event report storage and added Voltage Sag/Swell/Interruption report
in Section 12: Standard Event Reports, Sag/Swell/Interruption Report, and
SER.
Updated format and cross-references, reissued complete manual.
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Date Code 20001006 Manual Change Information vii
SEL-351 Instruction Manual
Revision
Date Summary of Revisions
980508 This revision includes the following changes:
− Added Power Elements to Section 3: Overcurrent, Voltage, Synchronism
Check, Frequency, and Power Elements.
− Added Load Profiling to Section 8: Breaker Monitor, Metering, and Load
Profile Functions.
− Updated Relay Word and explanations in Section 9: Setting the Relay.
− Added COM and LOO commands to Section 10: Serial Port
Communications and Commands.
− Updated Event report and explanations in Section 12: Standard Event
Reports and SER.
− Clarified DNP implementation details in Appendix H: Distributed Network
Protocol (DNP) V3.00.
− Added Appendix I: Mirrored Bits.
− Synchronism-check voltage input logic in Figure 3.26 was clarified. Voltage
input VA(or VAB for delta), provides frequency determination and has to be
within the “healthy voltage” window (indicated by new Relay Word bit 59VA).
− Positive-sequence voltage-polarized directional element logic in Figure 4.15 is
clarified with respect to the three-phase current threshold element 50P32 (was
previously shown in the wrong place).
− The OPEN command is no longer embedded in the trip logic in Figure 5.1 (see
the Note following 4.2) or in the drive-to-lockout logic (see the Note in the
Lockout State discussion, following Table 6.1).
− Execution of the OPEN command no longer prevents the COMM target LED
from illuminating for a trip. This provides additional options for the COMM
target LED, discussed in the Front-Panel Target LEDs subsection at the end
of Section 5: Trip and Target Logic.
− Relay Word bit TRGTR (Target Reset) is now available and provides
additional options, detailed in Figure 5.17 and accompanying discussion.
− The CLOSE command is no longer embedded in the close logic in Figure 6.1
(see the Note in the SET Close discussion, following Figure 6.1, for more
information).
− Relay Word bit 52A (Circuit Breaker Status) is now available and provides
additional options, detailed near the end of the Close Logic subsection in
Section 6: Close and Reclose Logic.
− Additional Relay Word bits 59VA, TRGTR, and 52A added to Row 34 in
Tables 9.4 and 9.8.
− Revisions were made to accommodate hardware changes related to model SEL-
03510J/03511J, which are connectorized™. New drawings were added to
Section 2: Installation, and various model-specific text references were
updated throughout the manual.
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viii Manual Change Information Date Code 20001006
SEL-351 Instruction Manual
Revision
Date Summary of Revisions
970815 This revision includes the following changes:
Added Delta-Connected Voltage Ordering Option:
−− Voltage input and metering specifications updated in the General
Specifications subsection in Section 1: Introduction and Specifications.
−− Voltage element specifications updated in Section 3: Overcurrent, Voltage,
Synchronism Check, and Frequency Elements.
−− The nonavailability of the zero-sequence voltage-polarized directional element
explained in subsections Directional Control for Neutral Ground and
Residual Ground Overcurrent Elements and Directional Control Settings
(setting ORDER) in Section 4: Loss-of-Potential, Load Encroachment, and
Directional Element Logic.
−− Voltage element specifications updated in the Settings Sheets at the end of
Section 9: Setting the Relay.
−− Low-Level Test Interface added to Section 13: Testing and Troubleshooting.
−− Added DNP protocol to Settings Sheets at the end of Section 9: Setting the
Relay and to the Software Protocol in Section 10: Serial Port
Communications and Commands. Added Appendix H.
−− Added part number (PARTNO) to Appendix B: Firmware Upgrade
Instructions.
970711 This revision includes the following changes:
Added SEL-351 Relay Models 035100 and 035101:
− Table 1.1 and accompanying text give an overview of the differences between
the various SEL-351 Relay Models.
− Table 1.1 references other figures that help explain the differences between the
various SEL-351 Relay models.
− Section 2: Installation has been extensively rewritten to better explain
differences between the various SEL-351 Relay models.
− Settings Sheets at the end of Section 9: Setting the Relay have been expanded
to include the settings for extra optoisolated inputs and output contacts in the
new SEL-351 Relay models. Also added enable setting references. Table 9.1
references the different Settings Sheets. Table 9.3 references other tables that
explain the Relay Word bit differences between the various SEL-351 Relay
models.
− Table 10.1 lists serial port information for all the SEL-351 Relay models.
−− Table 12.3 explains the differences in displaying optoisolated input and output
contact information in the event reports for the SEL-351 Relay models.
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Date Code 20001006 Manual Change Information ix
SEL-351 Instruction Manual
Revision
Date Summary of Revisions
Added 0.05 A Ordering Option for Channel IN [Sensitive Earth Fault (SEF)
Applications]:
− Current input, overcurrent, and metering specifications updated in the General
Specifications subsection in Section 1: Introduction and Specifications.
− Neutral ground overcurrent element pickup specifications updated in
Section 3: Overcurrent, Voltage, Synchronism Check, and Frequency
Elements.
− The nonavailability of the channel IN current-polarized directional element
explained in subsections Directional Control for Neutral Ground and
Residual Ground Overcurrent Elements and Directional Control Settings
(setting ORDER) in Section 4: Loss-of-Potential, Load Encroachment, and
Directional Element Logic.
− Neutral Ground demand current pickup specifications updated in Table 8.3 in
Section 8: Monitoring and Metering Functions.
− Neutral ground overcurrent element and demand current pickup specifications
updated in the Settings Sheets at the end of Section 9: Setting the Relay.
Channel IN current transformer ratio setting (CTRN) range expanded to
10,000.
Modified Recloser Logic:
− Relay goes to the Lockout State for Open Command execution [see OPE
Command (Open Breaker) in Section 10: Serial Communications and
Commands].
Other Significant Manual Changes:
General Specifications in Section 1: Introduction and Specifications:
− Updated specifications in AC Voltage Inputs, AC Current Inputs, Output
Contacts, and Routine Dielectric Test.
−− Added IEC 255-22-4 and IEC 255-21-3.
− Expanded on MW / MVAR metering accuracy specifications.
970326 This revision includes the following changes:
− Section 1, Page 1-11 - changed Phase Angle Accuracy to ±0.5°.
− Section 3, Page 3-26 - enlarged Figure 3.20 (date code not changed).
− Section 4, Page 4-3 - fixed format of Figure 4.2 (date code not changed).
− Section 7, Page 7-17 - reprint to fix printer error (date code not changed).
− Section 8, Pages 8-8 to 8-12 - reprint to fix printer error affecting Figures 8.1,
8.2, and 8.4 - 8.7 (date code not changed).
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xManual Change Information Date Code 20001006
SEL-351 Instruction Manual
Revision
Date Summary of Revisions
− Section 9, Page 9-7 - add clarifying statement to text preceding Table 9.3.
− Section 9,Settings Sheets, Page 7 of 18 - fix typographical error under
Reclosing Relay;Page 10 of 18 - add clarifying statement to text at top of
page.
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Date Code 20001006 Table of Contents i
SEL-351 Instruction Manual
SEL-351 INSTRUCTION MANUAL
TABLE OF CONTENTS
SECTION 1: INTRODUCTION AND SPECIFICATIONS
SECTION 2: INSTALLATION
SECTION 3: OVERCURRENT, VOLTAGE, SYNCHRONISM CHECK,
FREQUENCY, AND POWER ELEMENTS
SECTION 4: LOSS-OF-POTENTIAL, LOAD ENCROACHMENT, AND
DIRECTIONAL ELEMENT LOGIC
SECTION 5: TRIP AND TARGET LOGIC
SECTION 6: CLOSE AND RECLOSE LOGIC
SECTION 7: INPUTS, OUTPUTS, TIMERS, AND OTHER CONTROL LOGIC
SECTION 8: BREAKER MONITOR, METERING, AND LOAD PROFILE
FUNCTIONS
SECTION 9: SETTING THE RELAY
SECTION 10: SERIAL PORT COMMUNICATIONS AND COMMANDS
SECTION 11: FRONT-PANEL INTERFACE
SECTION 12: STANDARD EVENT REPORTS, SAG/SWELL/INTERRUPTION
REPORT, AND SER
SECTION 13: TESTING AND TROUBLESHOOTING
SECTION 14: APPENDICES
Appendix A: Firmware Versions
Appendix B: Firmware Upgrade Instructions
Appendix C: SEL Distributed Port Switch Protocol
Appendix D: Configuration, Fast Meter, and Fast Operate Commands
Appendix E: Compressed ASCII Commands
Appendix F: Setting Negative-Sequence Overcurrent Elements
Appendix G: Setting SELOGIC®Control Equations
Appendix H: Distributed Network Protocol (DNP) V3.00
Appendix I: MIRRORED BITS™
SECTION 15: SEL-351 RELAY COMMAND SUMMARY
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Date Code 20001006 Introduction and Specifications i
SEL-351 Instruction Manual
TABLE OF CONTENTS
SECTION 1: INTRODUCTION AND SPECIFICATIONS.......................... 1-1
SEL-351 Relay Models.............................................................................................................1-1
Instruction Manual Sections Overview......................................................................................1-3
Applications.............................................................................................................................1-7
Hardware Connection Features .................................................................................................1-8
Communications Connections.................................................................................................1-12
General Specifications............................................................................................................1-13
Processing Specifications ................................................................................................1-17
Relay Element Pickup Ranges and Accuracies.................................................................1-17
Instantaneous/Definite-Time Overcurrent Elements ..................................................1-17
Time-Overcurrent Elements.....................................................................................1-18
Under- and Overvoltage Elements............................................................................1-18
Synchronism-Check Elements..................................................................................1-18
Under- and Overfrequency Elements ........................................................................1-19
Timers............................................................................................................................1-19
Substation Battery Voltage Monitor ................................................................................1-19
Metering Accuracy..........................................................................................................1-19
Power Element Accuracy ................................................................................................1-20
TABLES
Table 1.1: SEL-351 Relay Models.....................................................................................................1-1
Table 1.2: SEL-351 Firmware Versions.............................................................................................1-3
FIGURES
Figure 1.1: SEL-351 Relays Applied Throughout the Power System....................................................1-7
Figure 1.2: SEL-351 Relay Inputs, Outputs, and Communications Ports (Model 0351xT)...................1-8
Figure 1.3: SEL-351 Relay Inputs, Outputs, and Communications Ports (Models 0351x0,
0351x1, and 0351xY; Models 0351x1 and 0351xY Have an Extra I/O Board –
See Next 2 Figures)....................................................................................................1-9
Figure 1.4: SEL-351 Relay Extra I/O Board (Model 0351xY, Plug-In Connector Version; Main
Board Shown in Figure 1.3)......................................................................................1-10
Figure 1.5: SEL-351 Relay Extra I/O Board (Model 0351x1, Screw-Terminal Block Version;
Main Board Shown in Figure 1.3).............................................................................1-11
Figure 1.6: SEL-351 Relay Communications Connections Examples.................................................1-12
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Date Code 20001006 Introduction and Specifications 1-1
SEL-351 Instruction Manual
SECTION 1: INTRODUCTION AND SPECIFICATIONS
This section includes the following overviews of the SEL-351 Relay:
SEL-351 Relay Models
Instruction Manual Sections
Applications
Hardware Connection Features
Communications Connections
General Specifications
SEL-351 RELAY MODELS
This instruction manual covers the following SEL-351 Relay models:
Table 1.1: SEL-351 Relay Models
Model
Number Rack Unit Height Number of Isolated I/O
Contacts
Rear-Panel
Connection
Type
Output
Contact Type Reference Figures
0351xT
(and old
0351xM)
2U 8/12 plug-in
connectors standard or high-current
interrupting
1.2, 2.2, 7.1,
7.28
0351x0 2U 6/8 screw-terminal
block standard 1.3, 2.3, 7.2, 7.29
0351x1 3U 6/8 (main board) screw-terminal
block standard 1.3, 2.4, 2.5, 7.2, 7.29
8/12 (extra I/O
board) screw-terminal block standard or high-current
interrupting
1.5, 2.4, 2.5,
7.3, 7.30
0351xY
(and old
0351xJ)
3U same as 0351x1 plug-in
connectors same as 0351x1 1.3, 1.4, 2.4, 2.5, 2.6, 7.2,
7.3, 7.29, 7.30
Old models 0351xM and 0351xJ have been superseded by models 0351xT and 0351xY,
respectively. This is due to improvements in Connectorized®SEL-351 Relays (plug-in connectors)
– see Section 2: Installation for more details. Unless otherwise noted, references to models
0351xT and 0351xY also apply to old models 0351xM and 0351xJ, respectively.
The model numbers are derived from the SEL-351 Relay ordering information sheet. The model
numbers in Table 1.1 are only the first part of an actual ordering number – enough to distinguish
one model type from another. The “x” field indicates the firmware version (see Table 1.2).
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1-2 Introduction and Specifications Date Code 20001006
SEL-351 Instruction Manual
These numbers should not be used to order an SEL-351 Relay. Refer to the actual ordering
information sheets.
Model 0351x0 and 0351x1 differ only in that model 0351x1 has an extra I/O board (and thus
increased rack unit height – see Figure 2.1). Model 0351xY is similar to model 0351x1, except
that it has plug-in connectors.
A vertical SEL-351 Relay is available in the 0351x1 and 0351xY models only (see Figure 2.5).
The vertical relays use the same rear panels as the horizontal 0351x1 and 0351xY models in
Figure 2.4. Though Figure 2.4 shows the extra I/O board (OUT201 through IN208) for model
0351x1, the vertically-mounted version of this model can be ordered without this extra I/O board
(the space appears blank). Any SEL-351 Relay model can be ordered with sensitive Earth Fault
(SEF) neutral ground overcurrent elements.
Voltage element differences due to wye- or delta-connected voltage inputs are detailed in Section 3:
Overcurrent, Voltage, Synchronism Check, Frequency, and Power Elements. Neutral ground
overcurrent element differences due to 0.05 A nominal channel IN (SEF) are detailed in the same
section. Certain ground directional elements are nonoperational if the SEL-351 Relay is ordered
with delta-connected voltage inputs or 0.05 A nominal channel IN (see Section 4: Loss-of-
Potential, Load Encroachment, and Directional Element Logic). See Figure 1.2 and Figure 1.3
for more information on voltage input and SEF options.
Throughout this instruction manual, when differences among the SEL-351 Relay models in
Table 1.1 are explained, model numbers are referenced for clarity. Most of the examples in this
instruction manual are for SEL-351 Relay model 0351xT – it was the first released SEL-351
Relay model (actually first released as model 0351xM; see Table 1.1).
Differences between model 0351xT and models 0351x0, 0351x1, and 0351xY show up in refer-
ences to optoisolated inputs, output contacts, and board jumpers. See the Reference Figures in
Table 1.1 for the numbering differences between model 0351xT and models 0351x0 and 0351x1
(e.g., optoisolated input labeled as IN1 on model 0351xT, compared to IN101 on model 0351x0).
Figure 2.15 through Figure 2.18 and Table 2.2 through Table 2.8 show the labeling differences
between the board jumpers.
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Date Code 20001006 Introduction and Specifications 1-3
SEL-351 Instruction Manual
Table 1.2: SEL-351 Firmware Versions
Model Number Firmware Version Relay Features
03510 0 Standard features.
03511 1 Standard features plus MIRRORED BITS™and load
profiling.
SEL-351 Relays with firmware version 0 can be upgraded to firmware version 1. However,
SEL-351 Relays with firmware versions 0 and 1 cannot be upgraded to any higher firmware
versions. This is due to hardware limitations.
The wye-connected voltage inputs for SEL-351 Relays with firmware version 0 or 1 are rated
for voltages up to 150 Vac, line-to-neutral (channel VS, too).
The delta-connected voltage inputs for SEL-351 Relays with firmware version 0 or 1 are rated
for voltages up to 300 Vac, line-to-line (channel VS, too).
03512 2 Includes firmware version 1 features plus power
elements.
03513 3 Includes firmware version 1 features plus voltage
sag/swell/interruption elements.
03514 4 Includes firmware version 1 features plus power and
voltage sag/swell/interruption elements.
SEL-351 Relays with firmware versions 2, 3, or 4 come with wye-connected voltage inputs only
(connect any voltage up to 300 Vac, line-to-neutral).
INSTRUCTION MANUAL SECTIONS OVERVIEW
The following is an overview of the other sections in this instruction manual:
Section 2: Installation describes how to mount and wire the SEL-351 Relay. Connections
for numerous applications are described. The operation of circuit board jumpers is explained.
Figure 2.2 through Figure 2.5 show the SEL-351 Relay front and rear panels.
Section 3: Overcurrent, Voltage, Synchronism Check, Frequency, and Power Elements
describes the operation of:
• Instantaneous/definite-time overcurrent elements (phase, neutral ground, residual
ground, and negative-sequence)
• Time-overcurrent elements (phase, neutral ground, residual ground, and negative-
sequence)
• Voltage elements (single-phase, phase-to-phase, etc.)
• Synchronism check elements
• Frequency elements
• Power Elements (in Firmware Versions 2 and 4)
• Voltage Sag/Swell/Interruption Elements (in Firmware Versions 3 and 4).
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1-4 Introduction and Specifications Date Code 20001006
SEL-351 Instruction Manual
Section 4: Loss-of-Potential, Load Encroachment, and Directional Element Logic
describes the operation of:
• Loss-of-potential logic and its effect on directional elements
• Load-encroachment logic and its application to phase overcurrent elements
• Voltage-polarized and current-polarized directional elements
• Best Choice Ground Directional™ logic and automatic settings
Section 5: Trip and Target Logic describes the operation of:
• General trip logic
• Switch-onto-fault trip logic
• Communications-assisted trip logic
• Front-panel target LEDs
Most tripping applications (not requiring switch-onto-fault or communications-
assisted tripping) require only SELOGIC®Control Equation trip setting TR and
unlatch trip setting ULTR in the general trip logic (see Figure 5.1).
Section 6: Close and Reclose Logic describes the close logic operation for:
• Automatic reclosures
• Other close conditions (e.g., manual close initiation via serial port or optoisolated
inputs)
Section 7: Inputs, Outputs, Timers, and Other Control Logic describes the operation of:
• Optoisolated inputs (IN1 through IN8 - model 0351xT; IN101 through IN106 -
models 0351x0, 0351x1, and 0351xY; IN201 through IN208 - models 0351x1 and
0351xY)
• Local control switches (local bit outputs LB1 through LB8)
• Remote control switches (remote bit outputs RB1 through RB8)
• Latch control switches (latch bit outputs LT1 through LT8)
• Multiple setting groups (six available)
• Programmable timers (timer outputs SV1T through SV16T)
• Output contacts (OUT1 through OUT11 and ALARM - model 0351xT; OUT101
through OUT107 and ALARM - models 0351x0, 0351x1, and 0351xY; OUT201
through OUT 212 - models 0351x1 and 0351xY)
• Rotating default displays
Courtesy of NationalSwitchgear.com