u-series v24 int n00-502 r01

NU-LEC INDUSTRIES PTY LTDA Schneider Electric Company

TECHNICAL MANUAL

FOR

U27-12POLE MOUNTED RECLOSER

(International Terminology Version)

SCOPEThis document describes the features and operation of the U-Series Automatic Circuit

Recloser as well as the installation and maintenance procedures.

Document Part No: N00-502Document Revision Level: R 01

COPYRIGHT NU-LEC INDUSTRIES PTY LTD 2000

U-Series Technical Manual

Nu-Lec Industries Pty Ltd.

ACN 085 972 425

37 South Street,

Lytton,

QLD 4178,

Australia.

Tel +61 7 3249 5444

Fax +61 7 3249 5888

LIMITATIONS

This document is copyright and is provided solely for the use of the recipient. It is not to becopied in any way, nor its contents divulged to any third party, nor to be used as the basis of atender or specification without the express written permission of Nu-Lec Industries Pty Ltd.This document discloses confidential intellectual property that belongs to Nu-Lec Industries P/L.This document does not invest any rights to Nu-Lec Industries intellectual property in therecipient. Moreover the recipient is required not to disclose any of the intellectual propertycontained in this document to any other party unless authorised in writing by Nu-Lec IndustriesPty Ltd.


CONTENTS1 Introduction................................................................................12 Scope of this Technical Manual ...............................................3

2.1 General.................................................................................................................32.2 Equipment Versions Covered by this Manual ....................................................32.3 Controller Version Covered by this Manual........................................................32.4 Software Identification System............................................................................32.5 Software Version Covered by this Manual .........................................................42.6 Related Documents.............................................................................................42.7 Year 2000 Compliance Statement......................................................................4

3 Specification ..............................................................................53.1 Environmental ......................................................................................................53.2 Recloser ...............................................................................................................5

3.2.1 Basic Timings................................................................................................53.2.2 Ratings...........................................................................................................53.2.3 Breaking Duty................................................................................................63.2.4 Duty Cycle .....................................................................................................63.2.5 Terminal Clearance/Creepage.....................................................................63.2.6 Current Transformers ...................................................................................6

3.3 Control Cubicle.....................................................................................................63.3.1 Radio/Modem................................................................................................73.3.2 Local Operator Controls................................................................................73.3.3 Control Electronics Thermal Constraints .....................................................7

3.4 Protection and Auto Reclose Functions .............................................................73.4.1 Inverse Time Protection................................................................................73.4.2 Definite Time Protection ...............................................................................83.4.3 Instantaneous Protection..............................................................................83.4.4 Sensitive Earth Fault Protection (SEF) ........................................................83.4.5 Cold Load Pickup..........................................................................................83.4.6 Inrush Restraint .............................................................................................93.4.7 Loss Of Phase Protection.............................................................................93.4.8 Live Load Blocking........................................................................................93.4.9 High Current Lockout....................................................................................93.4.10 Automatic Protection Group Selection.......................................................93.4.11 Auto-Reclose.............................................................................................103.4.12 Directional Blocking...................................................................................103.4.13 Other Protection Features ........................................................................103.4.14 Loss of Supply Detection..........................................................................10

3.5 Power System Measurements..........................................................................113.5.1 General ........................................................................................................113.5.2 Demand History ..........................................................................................113.5.3 Event History ...............................................................................................11

4 Recloser Construction and Operation...................................134.1 Recloser Mounting.............................................................................................134.2 Manual Trip ........................................................................................................134.3 Line Connection/Terminals ...............................................................................134.4 Surge Arresters..................................................................................................134.5 Control Cubicle Connection...............................................................................134.6 Recloser Memory...............................................................................................144.7 Contact Life ........................................................................................................144.8 Line Voltage Sensing.........................................................................................14


5 Control Cubicle ....................................................................... 175.1 Tropical, Moderate and Temperate Versions...................................................175.2 Equipment Panel................................................................................................175.3 Radio Mounting Tray Space..............................................................................205.4 Sealing & Condensation ....................................................................................205.5 Mounting & Earthing...........................................................................................205.6 Auxiliary Power Source......................................................................................215.7 Auxiliary Supply Control Cubicle Options..........................................................215.8 Cable Entry .........................................................................................................225.9 Current Injection Point........................................................................................225.10 Computer Port ..................................................................................................22

6 Control Electronics Operation............................................... 236.1 Control & Protection Module (CAPM) ...............................................................236.2 Operator Panel Subsystem (OPS)....................................................................236.3 Control Cable Entry Module (CCEM)................................................................236.4 Description of Operation ....................................................................................24

7 Operator Control Panel .......................................................... 277.1 Turning on the Control Panel.............................................................................277.2 Organisation of Liquid Crystal Display...............................................................287.3 Microprocessor Running LED............................................................................287.4 TRIP/CLOSE Keys, ENABLE/ISOLATE Switches ..........................................287.5 Display Groups...................................................................................................287.6 Selecting Displays ..............................................................................................297.7 Changing Settings..............................................................................................29

7.7.1 Use of Quick Keys.......................................................................................307.7.2 Use of SELECT , and MENU Keys....................................................30

7.8 Password Protection ..........................................................................................308 Work Tags and Controller Mode............................................ 31

8.1 Local/Remote Mode...........................................................................................318.1.1 Local Mode ..................................................................................................318.1.2 Remote Mode..............................................................................................31

8.2 Work Tagging.....................................................................................................318.3 Definition of Local or Remote User ...................................................................32

9 Protection ................................................................................ 339.1 Overview.............................................................................................................339.2 Multiple Groups of Protection Settings..............................................................339.3 Operator Settings ...............................................................................................339.4 Protection OFF ...................................................................................................349.5 Sensitive Earth Fault Control .............................................................................349.6 Earth Fault Control .............................................................................................349.7 Changing Protection Settings ............................................................................349.8 Overcurrent Protection.......................................................................................359.9 Inverse Time Protection.....................................................................................36

9.9.1 Protection Curves ........................................................................................389.9.2 Interactions between curve parameters.....................................................39

9.10 Definite Time Protection...................................................................................429.11 Sensitive Earth Fault (SEF) .............................................................................429.12 Loss Of Phase Protection................................................................................439.13 Live Load Blocking...........................................................................................439.14 Auto-Reclose....................................................................................................439.15 Sequence Reset...............................................................................................449.16 Lockout .............................................................................................................44

9.16.1 High Current Lockout ................................................................................449.17 Single Shot Mode.............................................................................................459.18 Inrush Restraint ................................................................................................45


9.19 Cold Load Pickup (CLP)..................................................................................479.19.1 Cold Load Pickup Example......................................................................489.19.2 Cold Load Pickup Status Display.............................................................499.19.3 Operator Control of Cold Load Pickup.....................................................49

9.20 Sequence Control............................................................................................499.21 Automatic Protection Group Selection ...........................................................509.22 Fail to Operate Under Protection ....................................................................50

10 Directional Blocking................................................................5110.1 Characteristic Angle and Fault Regions .........................................................5110.2 Phase Directional Blocking..............................................................................5210.3 Earth/SEF Directional Blocking.......................................................................5210.4 Earth Residual Voltage Balancing ..................................................................5410.5 SEF Residual Voltage Alarm ..........................................................................5410.6 Event Record ...................................................................................................5410.7 Configuration pages.........................................................................................5610.8 Parameters to be Configured..........................................................................59

11 Event Log .................................................................................6111.1 Event Log Display Updating............................................................................6111.2 Protection Generated Events..........................................................................6111.3 Loss of Supply Events.....................................................................................63

12 Power System Measurements................................................6512.1 Power System Frequency...............................................................................6512.2 Switchgear Terminal Designation...................................................................6512.3 Power Flow Direction.......................................................................................6512.4 Real Time Displays..........................................................................................66

12.4.1 Phase to Earth Voltages...........................................................................6612.4.2 Phase to Phase Voltages.........................................................................6712.4.3 Terminal Live / Dead Indication................................................................67

12.5 Averaged Data Displays..................................................................................6812.6 Maximum Demand Data Displays..................................................................68

13 Supply Outage Measurement .................................................7113.1 Determination of Supply Outage.....................................................................7113.2 Configuration and Display ...............................................................................7113.3 Resetting the Counters and Timers................................................................7213.4 Event Record ...................................................................................................73

14 Loop Automation.....................................................................7515 Communications Interfaces ...................................................77

15.1 V23 Interface....................................................................................................7715.2 RS232 Interface...............................................................................................7815.3 Radio/Modem Power.......................................................................................7815.4 Connections Into Electronics Compartment...................................................79

16 Input Output Expander (IOEX) Card ......................................8116.1 Field Excitation.................................................................................................8116.2 IOEX as Local/Remote User...........................................................................8116.3 IOEX Status Page............................................................................................8116.4 Inputs................................................................................................................8216.5 Outputs.............................................................................................................8316.6 System Healthy Indicator ................................................................................8416.7 Power Consumption........................................................................................84

17 Accessories .............................................................................8517.1 Test and Training Set (TTS)............................................................................8517.2 Windows Switchgear Operating System (WSOS).........................................85

17.2.1 Electronics Compartment Computer Port (P9) .......................................8517.2.2 Telemetry Port (P8)...................................................................................85


17.2.3 Outline of Operation ..................................................................................8617.3 Manual Operation Set......................................................................................8617.4 Remote Control Panel .....................................................................................8617.5 External CVT ....................................................................................................87

18 Installation............................................................................... 8918.1 Unpacking & Checking ....................................................................................89

18.1.1 Contents of Crate ......................................................................................8918.1.2 Unpacking Procedure................................................................................8918.1.3 Plugging and Unplugging Control Cable..................................................9118.1.4 Testing & Configuring................................................................................9118.1.5 Transport to Site ........................................................................................92

18.2 Site Installation .................................................................................................9318.2.1 Tools Required ..........................................................................................9318.2.2 Parts Required (Not supplied by Nu-Lec Industries) ...............................9318.2.3 Site Procedure...........................................................................................93

18.3 HV Connections ...............................................................................................9418.4 Surge Arrester Mounting and Terminating .....................................................9518.5 Earthing.............................................................................................................9518.6 Protection of Radio Equipment..................................................................... 10118.7 IOEX Cabling................................................................................................. 10118.8 LV Auxiliary Power from Mains..................................................................... 10218.9 LV Auxiliary Power from Dedicated Utility Transformer .............................. 10218.10 Auxiliary Power from Integrated Transformer............................................ 10218.11 Transformer Switching................................................................................ 102

19 Maintenance .......................................................................... 10519.1 Recloser Maintenance.................................................................................. 10519.2 Control Cubicle Maintenance ....................................................................... 105

19.2.1 Control Cubicle Cleaning ....................................................................... 10519.2.2 Battery Replacement.............................................................................. 10519.2.3 Protection and Operation Check ........................................................... 10519.2.4 Door Seal................................................................................................ 105

19.3 Battery Care................................................................................................... 10519.4 Fault Finding.................................................................................................. 106

19.4.1 Control Cable Check.............................................................................. 10619.4.2 Switchgear Check .................................................................................. 10619.4.3 Control Cubicle Check ........................................................................... 107

19.5 Replacement of Electronic Modules ............................................................ 10819.6 Replacement of Cables ................................................................................ 10819.7 Fitting or Replacing Heater ........................................................................... 10819.8 Abnormal Operating Conditions................................................................... 108

19.8.1 Low Power Mode.................................................................................... 10819.8.2 Excess Close Operations....................................................................... 108

Appendix A - IEC255 Inverse Time Protection Tables................................ 109Appendix B - IEEE Inverse Time Protection Tables ................................... 111Appendix C - Non-Standard Inverse Time Protection Curves................... 113Appendix D - System Status Pages.............................................................. 123Appendix E - Protection Pages..................................................................... 129Appendix F - Measurement Pages ............................................................... 133Appendix G - List of Events .......................................................................... 135Appendix H - Replaceable Parts & Tools..................................................... 141Appendix I - Control Cubicle Schematics.................................................... 143Appendix J - Equipment Weights and Crate Dimensions.......................... 153Appendix K - External CVT Optional Accessory......................................... 155INDEX............................................................................................................... 163

U-Series Introduction

1

1 IntroductionThe Nu-Lec Industries U-Series Automatic Circuit Recloser is a state-of-the-art electronicallycontrolled outdoor, pole mounted, three phase recloser. The recloser is one of the Nu-LecIndustries family of outdoor switchgear optimised for remote control and automation schemes.The U-Series features vacuum interrupters enclosed in epoxy mouldings, eliminating the needfor insulants such as oil and gas. Operation is by magnetic actuator which does not rely on thepresence of HV supply. The mechanism is enclosed in a stainless steel tank (Note 1).A pole mounting bracket is supplied which makes installation quick and easy. Cables areconnected to the recloser using parallel groove clamps or cable lugs. Control electronics are housed in a stainless steel control cubicle designed for harshenvironmental conditions. An all-weather user-friendly control panel is provided for a localoperator. Remote monitoring and control can be provided without the addition of a remoteterminal unit (RTU).Please note:

Controller events are identified in the text by using single quotes. Refer Section11 (page 61).

References to Operator Control Panel display pages appear as {Display Group Page Title: Text}. Refer Section 7 (page 27).

Note 1: Production models preceding Serial No: 146700 were constructed with galvanised mild steel tanks.

U-Series Scope of this Technical Manual

3

2 Scope of this Technical Manual2.1 GeneralThis Technical Manual details the specification of the switchgear, its operation, installation andmaintenance.Whilst every care has been taken in preparation of this manual, no responsibility is taken for lossor damage incurred by the purchaser or user due to any error or omission in the document.Inevitably not all details of equipment are provided, nor are instructions for every variation orcontingency during installation, operation or maintenance. For additional information on specificproblems or requirements, please contact Nu-Lec Industries or your distributor.

2.2 Equipment Versions Covered by this ManualThis manual applies to the following equipment:

Pole Top Recloser - Model U27-12

Pole Top Control Cubicle - Model PTCC-TEM, PTCC MOD, PTCC-TRO

External CVT (optional acc) - Model CVT EXT 27The model numbers are shown on the equipment rating plates. If your equipment does notcorrespond to these numbers then this manual is not applicable. Please contact Nu-LecIndustries or your local distributor.

2.3 Controller Version Covered by this ManualThis manual applies to CAPM4 based controllers. The CAPM is explained in Section 6 (page23). When the Operator Control Panel is turned on the display will show the controller type. Refer Section 7 (page 27). If it does not show CAPM4 then this manual does not apply andyou should contact Nu-Lec Industries or your local distributor for advice on the correct manualrequired.

2.4 Software Identification SystemThe software loaded into the controller has two important identifiers:

The Software Version which has the form XXX-XX.XX. This identifies the exactsoftware loaded into the program memory on the controller.

The Configuration Number which has the form XXXXX. This identifies theconfiguration loaded into the database that controls what the software will do. For example whether the operator text displays are to be in English or anotherlanguage.

Note that in order to change functionality of the equipment it is sometimes necessary to changethe software, sometimes the configuration and sometimes both.In order to get technical support from Nu-Lec Industries or your distributor it is vital to note downthe software version and the configuration number of your equipment and to quote these whenmaking your enquiry. Without this it is impossible for Nu-Lec Industries customer service toidentify the software and provide correct support.The software version and the configuration number are both shown on the Operator ControlPanel on the {SYSTEM STATUS SWITCHGEAR WEAR/GENERAL DETAILS} page. Referto Section 7 (page 27) to find out how to use the Operator Control Panel.

U-Series Scope of this Technical Manual

4

A typical example of software version and configuration would be:

Software 024-45.00

Configuration 10087

2.5 Software Version Covered by this ManualThe electronic controller incorporates a software based microprocessor. The software can beconfigured for different capabilities such as directional protection, a variety of protocols, etc. Thisis called its Software Capability. The software version and configuration determine thefunctionality of the controller. Refer Section 2.4 (page 3).To find out if this manual applies to the software/configuration loaded in the controller it isnecessary to display the Software Capability list on the Operator Control Panel found on{SYSTEM STATUS - CAPABILITY}. Refer to Section 7 (page 27) to find out how to use theOperator Control Panel.Having found {SYSTEM STATUS - CAPABILITY} press select and use the arrow keys to viewthe capability list.If the capability declarations include:

then this manual applies, if not contact Nu-Lec Industries or your distributor. Note that themanual revision number is usually stated e.g. R01+ which means revision 01 or later of themanual.

2.6 Related DocumentsNot detailed in this document are the following which are covered by their own manuals:

Windows Switchgear Operating System (WSOS) Used to configure the recloserfrom a PC.

Test and Training Set (TTS) Used to test control cubicles.

Specific Telemetry Protocol Implementations - For communications to remotecontrol systems.

Workshop & Field Test Procedures A set of instructions on how to test theswitchgear.

Service Procedures A set of instructions on how to remove and replace thecontroller electronics.

For further information on these products refer to Nu-Lec Industries or your local distributor.

2.7 Year 2000 Compliance StatementThe CAPM4 controller complies with Rules 1, 2, 3 and 4 of the British Standards Institute Year2000 Conformity Requirement (DISC PD2000-1 A Definition of Year 2000 ConformityRequirements). A copy of this statement can be found on the Nu-Lec Industries Pty Ltd web site(http://www.nulec.com.au/).

U Recloser(International) Manual N00-502 R01+

U-Series Specification

5

3 SpecificationThis section is the specification of the recloser. For a complete understanding it is essential toalso read the other sections of the manual describing the equipment operation.Note that where timing, current, voltage or other measurement accuracy is given it is as apercentage of value unless otherwise stated.Appendix J (page 153) specifies the weight of the switchgear, control cubicle and other items.

3.1 EnvironmentalOperating Temperature (Note 1) -30 to +50COperating Humidity 0 to 100%Operating Solar Radiation 1.1kW/m maxOperating Altitude (Note 2) 3000m maxNote 1: Temperature range depends on control cubicle version.Note 2: Altitudes above 1,000 m must be derated as per ANSI C37.60.

3.2 RecloserRefer Figure 26 (page 97) and Figure 28 (page 99) for physical dimensions.

3.2.1 Basic TimingsOpening Time (Note 1) < 35msInterrupting Time (Note 2) < 45msFault Clearing Time on Instantaneous protection for fault > 4 x Setting Current (Note 1) < 70msTime to contact part from receipt of trip command by operator, telemetry protocol or IOEX < 300msTime to contact touch from receipt of close command by operator, telemetry protocol or IOEX < 300msNote 1: The precise definition of these times is given in ANSI C37.60.Note 2: This includes contact arcing time in circuit breaker.

3.2.2 RatingsRated Maximum Voltage (27 kV Rating) 27kVRated Maximum Voltage (15.5 kV Rating) 15.5kVRated Continuous Current 630 AmpRated Frequency 50/60HzRated Mainly Active (0.7pf) Breaking Capacity 630ARated Cable Charging Interrupting Current 25ARated Line Charging Interrupting Current 5ARated Transformer Magnetising Interrupting Current 22ARated Symmetrical Interrupting Current 12.5kARated Asymmetrical Making Current (Peak) 32.5kARated Symmetrical Making Current (RMS) 12.5kAShort Time Current for 3 Seconds 12.5kAShort Time Current Recovery Time 180sRated Impulse Withstand Voltage (27 kV Rating) 125kVRated Impulse Withstand Voltage (15.5 kV Rating) 110kVOpening/Closing Mechanism (Note 1) Latching Magnetic ActuatorD.C. Resistance Terminal/Terminal


6

3.2.3 Breaking DutyMechanical Operations 10,000Contact Wear 630A 10,000Contact Wear 2kA 1955Contact Wear 6kA 217Contact Wear 12kA 50Note 1: Recloser is rated for ANSI C37.60 duty cycle.Note 2: Contact wear is automatically calculated for each interrupter by the control cubicle on the basis of fault current

and mechanical operations. The remaining contact life is shown on the operator control panel. Refer to Section4.7 (page 14) for more detail.

3.2.4 Duty CycleMaximum allowable duty cycle at full short current rating:

Open-0.5s-Close/Open-2s-Close/Open-2s-Close/Open followed by 300 second recovery time.

3.2.5 Terminal Clearance/CreepageInsulator Material Type Outdoor Cyclo-Aliphatic Epoxy ResinPhase/Phase Centres 375mmCreepage distance 780mmTaut String clearance phase/ground (centre mount bracket) 295mmTaut String clearance phase/ground (end mount bracket) 295mmTaut String clearance phase/phase 325mm

3.2.6 Current TransformersRatio 2000:1Accuracy 10 Amp - 630 Amp 1% 1AAccuracy 630 Amp - 12,500 Amp 5%

Note that there is no access to current transformer connections on the equipment. This data issupplied for information only.

3.3 Control CubicleRefer to Figure 2 (page 18) for physical dimensions.

Standard Control Cable Length (Note 1) 7mMaximum Vertical Separation from Recloser with Standard Control Cable 5mMaintenance Interval (Note 2) 5 YearsAuxiliary Supply Voltage (Low voltage AC mains supply) As Ordered +10 -20%Required Auxiliary Supply Rating 50 VABattery 24V 6.5 AHBattery Hold Up Time from fully charged (Note 3) 5 DaysBattery Recharge Time (new battery to 80% nominal capacity) 10 HoursBattery Replacement Interval (Note 2) 5 YearsBattery Low Voltage (Note 4) 23VBattery High Voltage (Note 4) 32VEarthing (Note 5) 10mm Earth StudHeater Power (where fitted) 120WNote 1: Other Control Cable lengths available 4 and 11 metres.Note 2: Battery replacement interval is influenced by location, refer Section 19.3 (page 105).Note 3: Assumes no radio/modem power drain or IOEX card connected. At the end of the holdup period, power is

available for a minimum of 10 recloser operations. When exhausted the battery is disconnected.

Note 4: Temperature compensated at 48mV/C.Note 5: Earthing details in Section 18.5 (page 95) must be strictly adhered to.


7

3.3.1 Radio/ModemA radio or modem may be fitted by Nu-Lec Industries or by the utility for remote communications.Space, power and data interfaces are provided within the control cubicle.

Radio/Modem Power Supply Voltage (set by user) 5 15 VDCRadio/Modem Power Supply Continuous Current 3 ARadio/Modem Power Supply Max Current 5 A for 30 sec with 20% duty cycleRadio/Modem Space on Radio Panel 330 x 215 x 85mm

Radio/Modem Interface (Note 1) V23 or RS232Radio/Modem Power Shutdown Time 1-1440minsTiming Accuracy 10sNote 1: Further details in Section 15 (page 77).

3.3.2 Local Operator ControlsLocal Operator Control is through the Operator Control Panel, refer to later sections.

3.3.3 Control Electronics Thermal ConstraintsContinuous Primary Current 800AShort Time Primary Current 12.5kA for 3sShort Time Current Recovery Time 60sRecloser Operations (Note 1) 20 in 1 minute, 1 per minute thereafterNote 1: Further details in Section 19.8 (page108).

3.4 Protection and Auto Reclose FunctionsThe control electronics have in-built protection and auto-reclose relay functions as below.Separate setting currents are available for phase, earth fault and sensitive earth fault (SEF). Thesetting currents apply to all trips in a sequence. However curves, multipliers and otherparameters may be set separately for each trip in a sequence.Multiple sets of protection settings are available.For a full description of protection functions refers Section 9 (page 33).

3.4.1 Inverse Time ProtectionInverse Time Curves available refer Appendix A,B,CPhase Setting Current Range 10 1260 AmpEarth Setting Current Range 10 1260 AmpSetting Current Resolution 1 AmpSetting Current Accuracy (Note 1) 5%Maximum Current for which curve applies 12.5kAMaximum Setting Current Multiple for which curve applies x30Time Multiplier 0.05 2Time Multiplier Resolution 0.01Maximum Time to Trip (Note 2) 2 180sMaximum Time to Trip Setting Resolution 0.1sMinimum Time to Trip (Note 2) 0 2sMinimum Time to Trip Setting Resolution 0.01sAdditional Time to Trip (Note 3) 0 2sAdditional Time to Trip Setting Resolution 0.01sPhase Threshold Multiplier (Note 2) (Note 4) 1 10Resolution of Multiplier Setting 0.1Earth Threshold Multiplier (Note 2) (Note 4) 1 10Resolution of Multiplier Setting 0.1Timing Accuracy (Note 5) 5% 20 msNote 1: Current accuracy applies to protection relay function only and excludes accuracy of current transformers.Note 2: Applies to inverse time and instantaneous protection only.


8

Note 3: Applies to inverse time protection only.Note 4: A trip is inhibited when the line current < setting current x threshold multiplier.Note 5: Timing refers to time to initiate operation of switchgear. Switchgear opening and closing times are in

addition. Refer to Section 3.2.1 (page 5).

3.4.2 Definite Time ProtectionAvailable as an alternative to inverse time on phase and earth. Setting Current parameters areas for inverse time protection.

Definite Time Range 0.5 100.0 secDefinite Time Resolution 0.1 secTiming Accuracy (Note 1) 50 msNote 1: Timing refers to time to initiate operation of switchgear. Switchgear opening and closing times are in


3.4.3 Instantaneous ProtectionAvailable as an additional element on inverse time or definite time protection. Also available asan alternative without inverse time or definite time. Instantaneous protection can be applied toboth phase and earth protection.

Multiplier of Trip Current Setting (applies to both phase and earth) 1 30Resolution of Multiplier Setting 0.1Maximum Effective Setting 12.5 kATrip Current Setting Accuracy (Note 1) 10%Transient Overreach for X/R < 10 10 28dBSEF Trips in sequence to lockout 1 4Note 1: Current accuracy applies to protection relay function only and excludes accuracy of current transformers.Note 2: Timing refers to time to initiate operation of switchgear. Switchgear opening and closing times are in


3.4.5 Cold Load PickupThis is an additional protection feature, which operates with inverse time and instantaneousprotection.

Cold Load Multiplier Range 1 5Cold Load Multiplier Resolution 0.1Cold Load Time Constant Range 1 480 minutesCold Load Time Constant Resolution 1 minuteTiming Accuracy 1 minute


9

3.4.6 Inrush RestraintThis is an additional protection feature, which operates with inverse time and instantaneousprotection.

Inrush Restraint Multiplier Range 1 30Inrush Restraint Multiplier Resolution 0.1Inrush Restraint Time Range 0.05 30 secInrush Restraint Time Resolution 0.05 secTiming Accuracy 20ms

3.4.7 Loss Of Phase ProtectionThis is an additional protection feature, which operates independently of the protectionelements.

Loss of Phase Threshold Voltage range 2 15 kVLoss of Phase Threshold Voltage setting resolution 1 VLoss of Phase Threshold Voltage accuracy (Note 1) 5% 250VLoss of Phase Time range 0.1 100 secLoss of Phase Time resolution 0.1 secLoss of Phase Time accuracy 50msNote 1: Includes accuracy of voltage transformers in switchgear.

3.4.8 Live Load BlockingThis is an additional protection feature, which operates independently of the protectionelements. For Live Load Blocking to operate the switchgear must be installed with the load side connectedto the (I, II, III) terminals of the recloser, unless external CVT's are fitted.

Live Load Threshold Voltage Refer Section 3.5.1 (page 11)

3.4.9 High Current LockoutThis is an additional protection feature, which operates in conjunction with the protectionelements.

Maximum Effective Setting 12.5 kAMinimum Effective Setting 10 ACurrent Setting Resolution 1 AAccuracy 15%

3.4.10 Automatic Protection Group SelectionThis is an additional protection feature.

Auto Change Time 10 180 secAuto Change Time Resolution 1 sec


10

3.4.11 Auto-RecloseTrips in Sequence to Lockout 1 4Reclose Time after First Trip in Sequence 0.5 180 secReclose Time after Second and Third Trips in Sequence 2 180 secReclose Time, Timing Resolution 0.1 secReclose Time, Timing Accuracy (Note 1) 0.1 secSingle Shot Reset Time 1 180 secSingle Shot Reset, Timing Resolution 1 secSingle Shot Reset, Timing Accuracy 1 secSequence Reset Time 5 180 secSequence Reset, Timing Resolution 1 secSequence Reset, Timing Accuracy 1 secNote 1: Timing refers to time to initiate operation of switchgear. Switchgear opening and closing times are in


3.4.12 Directional BlockingSystem Phase/Earth Nominal Voltage for correct operation 2 16kVPhase Protection Blocking:

Characteristic Angle setting range -180 +180 degCharacteristic Angle setting resolution 1 degCharacteristic Angle accuracy 10 degTime to Determine fault direction 30 ms

Earth/SEF Protection Blocking:Characteristic Angle setting range -180 +180 degCharacteristic Angle setting resolution 1 degCharacteristic Angle accuracy from 2 5A earth current 30 degCharacteristic Angle accuracy from 5 20A earth current 20 degCharacteristic Angle accuracy above 20A earth current 20 deg

Earth Protection Blocking Time to determine fault direction 30 msSEF Protection Blocking Time to determine fault direction 500 msMinimum Phase /Earth Polarising Voltage for Phase Blocking to Operate 500VMinimum Residual Earth Polarising Voltage for Earth blocking to Operate (Note 1) 20 100%Minimum Residual Earth Polarising Voltage for SEF blocking to Operate (Note 1) 5 100%Residual Earth Voltage dynamic balance limit (Note 1) 20%Residual Earth Voltage dynamic balance rate 0.6% per secondMinimum SEF Definite time when Directional Blocking is ON 0.5 secondsNote 1: Expressed as % of Phase/Earth Voltage

3.4.13 Other Protection FeaturesFault Reset Time (Note 1) 50 800msFault Reset Time Accuracy 20msSequence control AvailableNote 1: Applies to all protection elements.

3.4.14 Loss of Supply DetectionLive Terminal Threshold Voltage Refer Section 3.5.1 (page 11)Loss/Restoration of Supply Timeout 0.1 100 secLoss/Restoration of Supply Timing Accuracy -0ms/+150 ms


11

3.5 Power System Measurements3.5.1 GeneralHV line measurements on all three phases are made as follows:

Voltage Range (True RMS Phase/Ground): 2 16kVVoltage Resolution 1 VVoltage Accuracy I terminals (Note 1) 2.5% 25VVoltage Accuracy X terminals (Notes 1, 6) 10% 25VLive Terminal Threshold Voltage range (Note 3) 2 15 kVLive Terminal Threshold Voltage setting resolution (Note 3) 1 VLive Terminal Threshold Voltage accuracy (Note 1) (Note 3) 5% 250VLive Terminal Threshold Hysteresis -20%Phase Current Range (True RMS) (Note 2) 2.5 800 AmpEarth Current Range (True RMS) (Note 2) 1 800 AmpCurrent Resolution 1 AmpPhase Current Accuracy (Note 1) 2.5% 2 Amp over range 10 800 AmpEarth Current Accuracy (Note 1) 2.5% 2 Amp over range 1 800 AmpMaximum Fault Current Measurement (Note 1) 15%Apparent Power Range (Note 4) 0 36 MVAApparent Power Resolution (Note 4) 1 kVAApparent Power Accuracy (Note 1) (Note 4) 5% over range 20 800 AmpReal Power Range (Note 5) -36 36 MWReal Power Accuracy (Notes 1 and 5) 5% of apparent powerReactive Power Range (Note 4) 0 36 MVARReactive Power Resolution (Note 4) 1 kVARReactive Power Accuracy (Note 1) (Note 4) 5% of apparent powerUnsigned Power Factor 0.5 1.0Power Factor Resolution 0.01Power Factor Accuracy 0.05Measurement Filter Time Constant (Step Response) 2sMeasurement Update Rate 0.5sNote 1: Includes accuracy of switchgear current and voltage transformers.Note 2: Measurements are zeroed for currents less than lower value in range.Note 3: Used for Live/Dead display, Live Load Blocking and Loss Of Supply detection.Note 4: In database for transmission by a protocol.Note 5: Used to accumulate kWh reading for weekly maximum demand data.Note 6: X terminal voltage measurement is available when optional accessory External CVTs are installed. See

Appendix K.

3.5.2 Demand HistoryAverage demand sample times 5, 15, 30, 60 minutes

The minimum storage times for the average/weekly demand are shown in the table below.Sample period

(minutes) 5 15 30 60

Minimum storage time(Days) 26 78 156 312

3.5.3 Event HistoryMinimum number of typical events stored in the event history 3,000 events

U-Series Recloser Construction and Operation

13

4 Recloser Construction and OperationThe recloser, shown in Figure 1 (page 15), uses ganged vacuum interrupters insulated withcyclo-aliphatic epoxy resin mouldings operated by a single magnetic actuator for both trippingand closing.The magnetic actuator is operated by capacitors in the control cubicle which are charged anddischarged by the electronic controller.An external pointer, easily visible on the side of the tank, indicates the position of the recloser.

4.1 Recloser MountingTwo kinds of mounting bracket are available. One mounts the recloser centred on the pole whilethe other mounts it so the pole is at one end. The brackets are suitable for both timber andconcrete poles. These are shown at Figure 26 (page 97) and Figure 28 (page 99) with specificinstallation details provided at Section 18.2 (page 93). Alternatively, the recloser can bemounted on a frame in a substation.

4.2 Manual TripOn the underside of the tank is the manual trip ring. When this is pulled down with a hook stickthe recloser trips. The manual trip ring will remain in the down position until returned to thenormal position by the operator. In the down position the recloser is mechanically locked openand electronically interlocked against closing.

4.3 Line Connection/TerminalsHigh voltage terminals are 20mm tin plated copper stems with M10 x 1.5 threaded holes at theend, refer to Figure 25 (page 95).This means that connections can be either:

Parallel groove connectors suitable for the cable type. These are readilyavailable in bi-metallic versions suitable for connecting to aluminium cables.

Standard lugs with 10mm diameter holes. This is generally only suited for cablesup to 70mm2. These are also available in bi-metallic versions.

The upper terminals are identified as the X-Side terminals (X, XX, XXX for the three phases) andthe lower terminals are identified as the I-Side terminals (I, II, III for the three phases). TheTerminal Markers are clearly visible on the side of the tank as shown at Figure 1 (page 15).

4.4 Surge ArrestersProvision of surge arresters is recommended to protect the recloser from over-voltage.Surge arrester brackets, which fit to the mounting bracket, can also be provided as an optionalextra. Refer to Figure 26 (page 97).

4.5 Control Cubicle ConnectionConnection to the control cubicle is by a control cable that plugs into the bottom of the recloser.The control cable can be orientated to suit the installation.Current transformers and voltage screens embedded in the epoxy resin mouldings send signalsto the control electronics which monitors phase current, earth current and phase/groundvoltages. The voltage screens are embedded in the I, II and III side mouldings, refer to Figure 1 (page 15). If the control cable is disconnected (at either end) the CTs and voltage screens areautomatically shorted by circuitry on the SCEM card inside the recloser.


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4.6 Recloser MemoryThe recloser incorporates an electronic memory which is used to record information for that unit.This information includes the following which is available on the operator display

Serial Number

Breaking Rating

Continuous Current Rating

Number of Mechanical Operations (incremented on close)

Rated Voltage

Contact Life Remaining (by phase)

4.7 Contact LifeThe vacuum interrupters in the recloser have the duty rating given in Section 3.2 (page 5). Thecontrol electronics measures the interrupted current every time the contacts open.This measured current is used to calculate the amount of contact wear each interrupter hassuffered and the contact life remaining is reduced accordingly.The remaining contact life is held in the switchgear memory and can be displayed on theOperator Control Panel.If remaining life reaches zero on any phase the recloser should be returned to Nu-Lec Industriesfor refurbishment.Note that since the actual breaking current is measured and since most faults are considerablylower than the maximum line fault current, a much longer service life is to be expected from thismethod of monitoring wear compared to a simple operations count method.

4.8 Line Voltage SensingThe standard U Series ACR senses line voltage on the I terminals.In normal closed operation this enables voltage measurement, power measurement, directionalblocking and so on.Some automation systems may require voltage sensing on both sides of the ACR when it isopen. To satisfy this requirement, optional Capacitive Voltage Transformers (CVT) may beinstalled to provide voltage sensing on the X terminals of the ACR.A comprehensive explanation of the CVT is given in Appendix K.


15

Figure 1: Recloser Features

U-Series Control Cubicle

17

5 Control CubicleThe control cubicle is purpose designed for outdoor pole mounted operation. The cubiclefeatures a hinged hatch for all weather access by operations staff and a door for access bymaintenance staff. Both the door and the hatch can be padlocked for security. Figure 2 (page18) shows the cubicles dimensions.

5.1 Tropical, Moderate and Temperate VersionsTropical, moderate and temperate climate versions of the control cubicle are available.

The tropical version is well ventilated and is suitable for climates where theambient temperature can reach 50C and only occasionally goes below 0C, witha lower limit of -10C.

The moderate version has reduced ventilation and is used in environments wherethe temperature rarely goes above 40C and occasionally goes below -5C with alower limit of -15C.

The temperate version has reduced ventilation and a heater fitted to theequipment panel. It is suitable to climates where the ambient temperature rarelygoes above 40C but can fall as low as -30C.

5.2 Equipment PanelInside the cover is an equipment panel with the following key features, refer to Figure 3 (page 19)and Control Cubicle Schematic 1 (page 143).

The mains compartment houses LV mains transformers (where fitted) andcircuit breakers for batteries and auxiliary supply.

The electronics compartment houses the Control and Protection Module(CAPM) and the Operator Panel Sub-System (OPS). This compartment issealed to protect the electronics from airborne pollution.

The battery compartment houses two 12 Volt batteries. The radio mounting tray is used to mount the communications radio, modem or

IOEX card (where fitted), refer Section 16 (page 81). This hinges downward toexpose the radio/modem and can be detached to allow workshop fitting of theradio/modem.

The Control Cable Entry Module provides termination and filtering for thecontrol cable, housed behind a removable panel. The incoming control cableconnects to P1 of the CCEM, the internal wiring loom N03-505 connects to P2 ofthe CCEM.

A Heater compartment for the control cubicle heater can be fitted.Running up the centre of the equipment panel is a rubber cable duct used to carry the internalwiring. The equipment panel can be removed by disconnecting external connections andunbolting. The equipment panel is arranged so the most heat sensitive components, the batteries, arelocated low down close to the air entry. In tropical situations this ensures the batteries staywithin a few degrees of ambient at all times thus maximising their life. Additionally, the partwhich generates the most heat, the mains power supply (where fitted), is located at the top of thecubicle where its heating effect on other parts is minimised.


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Figure 2: Control Cubicle


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Figure 3: Equipment Panel


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5.3 Radio Mounting Tray SpaceThe space available on the radio tray to install customer equipment is shown below.

Figure 4: Radio Mounting Space

5.4 Sealing & CondensationAll vents are screened against vermin entry and the door is sealed with replaceable foam tape. Complete sealing against water entry under all conditions is not expected, eg. during operation inthe rain with the hatch open. Instead, the design is such that if any water does enter, it will runout of the bottom without affecting the electrical or electronic parts. The well-vented and self-heating nature of the cubicle ensures moisture will dry out rapidly. The extensive use of stainlesssteel and other corrosion proof materials ensures the presence of moisture has no detrimentaleffects.Condensation can be expected to form under some atmospheric conditions such as tropicalstorms. However due to the insulated and well-vented design, any condensation will be on metalsurfaces where it is of no consequence. The water drains in the same way as any other waterentering the cubicle. Condensation will drain from the bottom and the interior will be dried byventilation and self heating.The Electronics Compartment, which houses the main electronic modules, is well sealed and isonly opened for electronic module replacement.

5.5 Mounting & EarthingThe control cubicle is mounted on the pole with bolts or strapping and is connected to therecloser by the detachable control cable. The control cubicle must be earthed to therecloser earthing scheme as detailed at Section 18.5 (page 95).


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5.6 Auxiliary Power SourceThe auxiliary supply is used to maintain charge on the sealed lead-acid batteries that providestandby power when auxiliary power is lost. The controller monitors the status of both theauxiliary and battery supplies.A low power mode is activated when the batteries are nearly exhausted due to loss of theauxiliary supply. This mode minimises power consumption while still maintaining basicfunctionality. Refer to Section 19.8 (page 108) for more information.Auxiliary power comes from one of two sources:

LV supplies provided by the utility. This connects into the control cubicle and iscalled an LV Supply. In this case the control cubicle is fitted with a suitabletransformer and its nameplate indicates the required auxiliary supply voltage.

HV line supply to a Voltage Transformer (VT) fitted outside the recloser tank. This external VT is connected into the recloser and is also called an IntegratedHV Supply. In this case the rating plate on the transformer indicates its voltagerating. Note that the VT is designed only for the Nu-Lec Industries control cubicleand cannot provide power for any other purpose.

Section 18.8 (page 102) gives details of auxiliary supply connection and earthing.

5.7 Auxiliary Supply Control Cubicle OptionsThe control cubicle can be manufactured in a number of different auxiliary supply configurationssuch as:

Single Aux Supply from LV;

Single Aux Supply from HV;

Dual Aux Supplies from LV; or

Dual Aux Supplies, one LV, one HV.The configuration is indicated on the control cubicle nameplate as:

AUX SUPPLY 240VAC (or other voltage) for LV supply;or AUX SUPPLY INTEGRATED for integrated HV supply.

The Miniature Circuit Breakers (MCB), located at the top of the control cubicle in the mainscompartment, protect the battery (centre MCB) and the auxiliary supplies.When equipped for Integrated HV Supply the Aux MCB should always be closed duringoperation or testing even if the auxiliary supply transformer is not energised. This ensurescorrect operation of the memory in the switchgear.For a single LV supply an AUX OUT socket can be factory fitted as an option to provide a poweroutlet in the control cubicle. This is shown in Figure 3 (page 19).For dual supplies two AUX supply MCBs are fitted, one for each supply.


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5.8 Cable EntryAll cables enter the control cubicle from the underside as shown in Figure 3 (page 19). Cableentries are provided for:

The control cable from the recloser that plugs into connector P1 at the bottom ofthe battery compartment.

One or two LV mains supplies (where fitted) which run behind the equipmentpanel. The two 20mm holes provided for cable entry can also be used forexternal I/O entry if required.

Communication Cable/Radio Antenna (where fitted), a 16mm hole is provided forcable entry.

5.9 Current Injection PointA six way connector called the "Current Injection Point" is located on the mains compartment.This is used with the Test and Training Set (TTS) to perform secondary injection while theswitchgear is connected. This allows injection of equipment in service without disconnection.

5.10 Computer PortA 25 way female D-type connector is located on the electronics compartment cover above theOperator Control Panel. This connects to an RS232 port on the electronic controller for use withthe Windows Switchgear Operating System (WSOS) on a portable computer. This port is alsoused to upgrade electronic controller operating software, including installation of new telemetryprotocols.

U-Series Control Electronics Operation

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6 Control Electronics OperationThe control system block diagram is shown in Figure 5 (page 25). The main features areexplained below.

6.1 Control & Protection Module (CAPM)The main module of control electronics is the Control and Protection Module (CAPM). Therecloser accompanying this manual uses Module Version 4, known as CAPM4. It is centredaround a microprocessor and carries out the following functions:

High speed sampling of the line Current Transformers (CTs), calculation of RMSphase current and earth spill current.

High speed sampling of the line Capacitive Voltage Transformers (CVTs),calculation of RMS phase/ground voltages.

Calculation of apparent, real and reactive power flows from the above.

Protection relay functions.

Auto-reclose relay functions.

Monitoring of recloser auxiliary switches.

Charging of the close and trip capacitors.

Discharging the close and trip capacitors into the magnetic actuator to operatethe recloser, either automatically or by local or remote operator command.

Charging of the battery from the auxiliary supply, changeover to battery on loss ofauxiliary supply and disconnection when the battery is exhausted.

Driving the Operator Panel Sub-system (OPS).

Driving the external communications interface to allow monitoring and controlfrom a remote computer or operator over a communications link.

Driving the Windows Switchgear Operating System (WSOS) over an RS232 link.The connector for this link is located on the electronics compartment above theoperator control panel.

The CAPM is a replaceable unit.

6.2 Operator Panel Subsystem (OPS)This comprises the electronics compartment cover, an operator control panel with LCD display, amembrane keyboard and its controlling microcomputer. The Operator Panel Subsystem is a replaceable unit.

6.3 Control Cable Entry Module (CCEM)This is located at the bottom of the battery compartment and provides termination and filtering forthe signals from the recloser. The CCEM is a replaceable unit.


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6.4 Description of OperationThe CAPM utilises a Motorola 68332 microprocessor, with 2Mbytes of non-volatile "Flash"EEPROM and 1Mbyte of volatile read/write static memory. The non-volatile memory is used tohold programs, configuration parameters and historical data. The volatile memory is used as runtime workspace. There are no user-adjustable hardware features on the CAPM, no links, no DILswitches and no variable resistors. Re-programming of the microprocessor can be carried outusing a built-in loader from a portable computer.On power-up, or when the switchgear is connected, the CAPM reads the data from the memoryinside the recloser. The memory data in the recloser includes error check codes enabling theCAPM to validate the data. The status of the data is then displayed on the operator panel. When a local operator presses buttons on the control panel a character is sent from theOperator Panel Subsystem to the CAPM, which then carries out the required command.The recloser operates when the CAPM discharges its trip or close capacitors into the recloseractuator. The CAPM continually monitors the capacitors and will only discharge them into therecloser solenoids if the charge is sufficient for correct recloser operation. In addition, the CAPMwill only close the recloser if there is sufficient charge in the trip capacitor to trip the recloser. Thisensures the recloser will always be ready to trip if closed onto a fault. If a trip or close requestoccurs when there is insufficient charge in the capacitors, it is discarded (this never happens innormal operation).If the isolate switches on the operator panel are in the isolate position or the switchgear isdisconnected or the recloser memory data cannot be read or is invalid, the CAPM will notattempt to operate the recloser and any control requests will be discarded. Refer Section 7.4(page 28).Current transformers and voltage screens in the recloser are monitored to provide the protectionand measurement functions.The switchgear, electronics and power supplies are monitored for correct operation. This data isused to generate a system healthy signal which is available either for transmission by atelemetry protocol or as an output on the optional IOEX (Input/Output Expander) module. Thiscan be used for remotely monitoring the health of the recloser.


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Figure 5: Control System Block Diagram

U-Series Operator Control Panel

27

7 Operator Control PanelThe Operator Control Panel is mounted in the control cubicle. It consists of a four-line LiquidCrystal Display and keyboard with switches, keys and LEDs. The keyboard is used to select andmonitor the functionality of the recloser. The control panel is simple and intuitive to use.

Figure 6: Operator Control Panel

7.1 Turning on the Control PanelThe PANEL ON/OFF key turns the panel on and off. When off, the display is blank and none ofthe keys work. The panel will turn itself off if no keys are pressed for ten minutes.When activated the control panel shows a start-up message for 5 seconds and then shows the{SYSTEM STATUS OPERATOR SETTINGS} display. However, if the time and date has notbeen set since the last restart then the operator must set it using the SELECT, and MENUkeys before other displays can be selected.


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7.2 Organisation of Liquid Crystal DisplayThe four-line liquid crystal display is usually organised as follows:

---------------- Page Title ----------------Data Field 1 Data Field 2Data Field 3 Data Field 4Data Field 5 Data Field 6

The six data fields are used differently on each display page. Display pages with this format areshown in Appendix D (page 123).Some special display pages are different. These are shown in the relevant sections in thismanual, Appendix E (page 129) and Appendix F (page 133).

7.3 Microprocessor Running LEDThe green MICROPROCESSOR RUNNING LED flashes at two (2) second intervals to indicatethe control electronics are running normally. If the flashing stops or becomes intermittent itindicates a fault condition (e.g. loss of power). The LED flashes at all times, even when theoperator panel is turned off.

7.4 TRIP/CLOSE Keys, ENABLE/ISOLATE SwitchesThe TRIP and CLOSE keys generate trip and close requests to the CAPM when the panel isactive. If the adjacent ENABLE/ISOLATE switch is in the ISOLATE position no requests will begenerated.When the switches are in the ISOLATE position the close and trip coils in the magnetic actuatorare disconnected from the control electronics. Thus the ENABLE/ISOLATE switchesconstitute physical isolation points for the control circuitry.Embedded in the TRIP/CLOSE keys are LED's that indicate the position of the recloser, red forclosed, green for open.

7.5 Display GroupsMany different displays are available. They are divided into four groups:

SYSTEM STATUS - has all the status information about the recloser and controlelectronics e.g. battery low, operations count, SEF enabled/disabled. Informationon this display group is given in Appendix D (page 123). All System Statusdisplays have a S in the top right corner.

EVENT LOG - shows the event record for the recloser. More information is givenin Section 11 (page 61) and in Appendix G (page 135).

MEASUREMENT - has all the information about the HV line measurementsmade e.g. line current, line voltages, maximum demand data. Refer to Section12 (page 65) and Appendix F (page 133). All Measurement displays have a Min the top right corner.

PROTECTION - has all the protection settings currently in use e.g. Trip CurrentSettings, curves, reclose times. More information is given in Section 9 (page 33)and Appendix E (page 129). All Protection displays have a P in the top rightcorner.

Within each group are multiple pages each showing different data.


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7.6 Selecting DisplaysThe MENU key selects the display group. The keys select further pages within the groupas shown in Figure 7.Therefore, to select a particular display page:

Press the MENU key to get the group on display. Press to get the page or sub-group required.

Press SELECT to get to the sub-page required, where necessary.

Figure 7: Display Page Organisation

7.7 Changing SettingsSettings can be changed in two ways:

The Quick Keys allow rapid changing of operator settings on the {SYSTEMSTATUS OPERATOR SETTINGS} page. Quick keys are located on the lowerright hand side of the panel.

The SELECT, , and MENU keys can be used to change all settings.


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7.7.1 Use of Quick KeysQuick Keys are a way to quickly change the settings commonly used by an operator or linesman.The following Quick Keys are available:

Quick Key Operator Setting ControlledLocal Remote Local Mode / Remote ModeEarth Prot SEF ON/OFF, Earth Fault ON / OFFAuto On/Off Auto Reclose ON/OFFCold Load Cold Load Pickup IDLE/ NO CHANGE/ MAX

These settings are all located on the {SYSTEM STATUS OPERATOR SETTINGS} pageused by the operator, refer to Appendix D (page 123).Some of these options may not be available to the operator if they have been disabled on the{SYSTEM STATUS OPTIONS} page.A Quick Key may be pressed at any time and has the effect of displaying the {SYSTEMSTATUS OPERATOR SETTINGS} page, with the selected field flashing.Subsequent entries of the selected Quick Key will cycle the flashing field through the optionsavailable and back to the display page previously selected.Pressing the ENTER key puts the newly selected setting into service.When a quick key is in use, the and SELECT keys are disabled and the HELP key bringsup a special message.

7.7.2 Use of SELECT , and MENU KeysOnly a few of the settings may be changed by use of the quick keys. However, all settings canbe changed by the following procedure:

Find the page on which the setting is shown (Press MENU). Press SELECT until the required setting starts to flash. Press keys to change the setting to the new value required. Press MENU to put the new setting into service.

7.8 Password ProtectionSome settings require passwords to be entered before they can be changed, refer to AppendixD (page 123).If a password protected field is selected for change the user is prompted for the password. Apassword (which can be up to five characters in length) is entered in the following way:

keys are pressed until the first character of the password is displayed. SELECT key is pressed. This sequence is repeated until the required number of characters has been

entered.Once this is done the password does not need to be entered again while the operator panel ison. When the operator panel turns off, however, the password will need to be re-entered forfurther setting changes.The password is factory set to , but can be changed by the user with the WindowsSwitchgear Operator System (WSOS) utility. The factory password does not have to beremembered, the controller prompts the operator for it automatically.

U-Series Work Tags and Controller Mode

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8 Work Tags and Controller ModeAn important feature of the controller is that it is always in one of two modes, Local or Remote,and can have a Work Tag applied by Local or Remote operators.The mode and the tag specify the circumstances under which the recloser can be closed toensure operational safety.

8.1 Local/Remote ModeThe Local/Remote selection is carried out on the {SYSTEM STATUS OPERATORSETTINGS} page. There is a quick key on the panel to make this fast and easy. Setting thismode ensures closing and tagging can only be carried out by the designated local or remoteusers. It is the equivalent of a Local/Remote switch on the front panel. Local/Remote does notaffect automatic closing.

Most importantly the Local/Remote mode can only be set from the OperatorControl Panel.

8.1.1 Local ModeIn this mode only a local user can manually close the recloser (the recloser can still closeautomatically with the auto-reclose function).This means a user can go to the control cubicle, set local control mode and know that remoteclosing is disabled.Only a local operator can apply/remove the Work Tag when the controller is in Local Mode.

8.1.2 Remote ModeIn this mode only a remote user can manually close the recloser (the recloser can still closeautomatically with the Auto-Reclose function).Only a remote operator can apply/remove the Work Tag when the controller is in Remote Mode.If the local operator is denied a close operation or a Work Tag due to being in Remote Modethen the operator panel will flash the message, Not Allowed Change to Local Control and/orremove Work Tag.

8.2 Work TaggingThe Work Tag is different. Application of the Work Tag ensures that no closing can take place atall, either by a local operator, a remote operator or automatically. Once applied, neither a localuser, remote user or the Auto-Reclose function can close the recloser.Applying a Work Tag activates the Single Shot Mode. This means a protection trip will alwaysgo to lockout when the Work Tag is set. Applying and removing tags is password protected.Work Tags are applied and removed from {SYSTEM STATUS SWITCHGEAR STATUS:Work Tag OFF}. When applied the operator panel flashes the message, Warning Work TagApplied on the title line.Note that only a local user can apply/remove the tag when the controller is in Local Mode andonly a remote user can apply/remove the tag when the controller is in Remote Mode. Thismeans that a local user can remove the Work Tag applied by a remote user but they must firstput the controller into Local Mode.If the local operator is denied a close operation due to the Work Tag being applied the operatorpanel will flash the message, Not Allowed Change to Local Control and/or remove WorkTag.

U-Series Work Tags and Controller Mode

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8.3 Definition of Local or Remote UserThere are three kinds of local user:

The Operator Control Panel.

An IOEX card designated as Local. This might apply, for example, to an IOEXcard used in a substation to provide control from a panel inside a building.

A Windows SOS (WSOS) computer plugged into the computer port on the frontof the user control panel, refer Section 17.2 (page 85).

There are two kinds of remote user: An IOEX card designated as Remote. This might apply, for example to an

IOEX card used to interface to a SCADA system remote terminal unit. ReferSection 16 (page 81).

A remote control protocol. These are almost always designated as remote users.Full information is given in the relevant protocol manual.

An IOEX is designated Local or Remote from the Operator Control Panel. Refer Section 16(page 81) and Appendix D (page 123), {SYSTEM STATUS IOEX Status}

U-Series Protection

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9 Protection9.1 OverviewThe controller has many different protection features described in this section. In summary itoperates as follows:

When there is a line fault the recloser is tripped. The Protection Elements arePhase, Earth, SEF and Instantaneous. Each individual element can beprogrammed to cause the trip depending on the relevant setting. There are avariety of ways to prevent nuisance tripping.

After a protection trip there will be a delay and then a reclose.

This trip/close sequence can be repeated a number of times with protectionelements programmed to change between each trip in the sequence.

If the fault cannot be cleared the controller goes to lockout and waits for anoperator to initiate the next close. There are a variety of ways the controller canbe made to go to lockout without completing the entire reclose sequence.

The controller stores up to ten groups of protection settings that can be selectedby the operator. These are referred to as Protection Groups A to J. Onceprogrammed, the protection settings rarely change.

In addition to the protection settings there are Operator Settings. This group ofsettings is independent of the protection settings and it changes the mainfunctionality of the recloser.

9.2 Multiple Groups of Protection SettingsThe controller supports up to ten completely independent Protection Groups. A ProtectionGroup is a group of settings, which changes the protection functionality of the recloser. Thesegroups are referred to as Protection Groups A to J.The operator selects either Group A, B, C, or J to be Active from {SYSTEM STATUS OPERATOR SETTINGS: Prot A J Active}.Whenever a new Protection Group is activated or a protection trip occurs, an event iswritten to the Event Log indicating which protection Group is now in operation. The eventlogged is for example Prot Group A Active; Prot Group F Active; etc.All the protection parameters are programmed and stored independently for each of the groups.For example, if the Sequence Reset Time is required to be 20 seconds in both A and B groups,then it must be explicitly set to 20 seconds in both groups of protection settings.Protection settings are usually set once by the protection engineer and are not altered duringnormal operation of the equipment.

9.3 Operator SettingsOperator Settings are different from Protection Settings. These may be used by an operator orlinesman, on an everyday basis, to set the controller into the required mode. For example, alinesman may want to disable Auto-Reclose and Sensitive Earth Fault prior to live line work.The Operator Settings are all found on the {SYSTEM STATUS OPERATOR SETTINGS}page. These are:

Local/Remote Control selection;

Earth Fault and Sensitive Earth Fault (SEF) protection ON/OFF selection;

Auto-Reclose ON/OFF;

U-Series Protection

34

Operational Cold Load Time and Multiplier, refer Section 9.19 (page 47); and

Selection of the Active Protection Group or Protection OFF.These operator settings are not affected by changing the Active Protection Group. For example;if Auto-Reclose is in force before the Active Group is changed from A to B then Auto-Reclose willalso be in force after the change.Note that the Earth Fault, Sensitive Earth Fault and Protection OFF settings may be unavailableto the operator if they have been disabled on the {SYSTEM STATUS OPTIONS} page.

9.4 Protection OFFThe selection of {SYSTEM STATUS OPERATOR SETTINGS: Protection OFF} inhibits allprotection pickups and deactivates all overcurrent protection as well as Loss of Phase Protectionso that it will only perform local/remote user trips and closes. Note that Live Load Blocking stilloperates even if Protection OFF is selected.A Protection OFF event is generated whenever the protection is turned off.It is possible to configure the controller so the Protection Off state cannot be reached. This isset using the {SYSTEM STATUS OPTIONS 1: Prot OFF Not Allowed} setting. In this casethe operator cannot select the Protection OFF state, only the active protection groups.Selecting {SYSTEM STATUS OPTIONS 1: Prot OFF Not Allowed} also has the effect ofturning on the protection if it is not already on.

9.5 Sensitive Earth Fault ControlSensitive Earth Fault (SEF) protection can be made either available or not available with the{SYSTEM STATUS PROTECTION SETTINGS 1: SEF Available/Not Available} setting.When not available, SEF is turned off and there are no facilities for the operator to turn it on.

9.6 Earth Fault ControlIt is also possible to disable control over Earth Fault protection with the {SYSTEM STATUS OPTIONS 1: E/F OFF Allowed/Not Allowed} setting. When Earth Fault OFF is set to NotAllowed, operator control of Earth Fault protection is disabled (and Earth Fault protection ispermanently ON). This can be used in conjunction with the SEF Available setting to restrictoperator control to SEF only.

9.7 Changing Protection SettingsAll protection parameters and operator settings are held in non-volatile memory on the CAPM.This ensures they are retained through power interruptions. However, if a different CAPM isinstalled in a control cubicle, or if the control cubicle is replaced, then the protection parametersneed to be re-programmed into the CAPM. This is carried out either through the operator panelor through Windows Switchgear Operator System (WSOS).The ten groups of protection settings are programmed on the protection pages. Passwordsare required to make changes.When programming protection settings the technician first selects which protection group ofparameters to display on {PROTECTION SETTING 1 (A J): Group A J Displayed}. Thisgroup can then be changed. Selecting a protection group to be displayed does not make itactive, that is done by the operator in the {SYSTEM STATUS OPERATOR SETTINGS: ProtA J Active} field.Because one protection group can be active and another protection group can be displayed (inthe protection pages), care must be taken or confusion will result. However, the title line of thedisplay always shows which protection group is currently being displayed by showing an A, Bor J suffix, such as {PROTECTION SETTING 3 E}.

U-Series Protection

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The operator can change either the active group or the inactive group. When changes are madeto the active group they do not go into service immediately. Instead the changes are saved intothe internal database in the controller and go into service when:

The operator moves off the protection group of pages,

The operator turns off the control panel,

The control panel turns itself off after the timeout period, or

The controller is powered off and on again.This allows the operator to edit the active group and then put the new settings into service as awhole. The operator is informed when the changes are going into service.When the active group is being edited, the page title flashes to indicate the settings being workedon are different to the ones in service.Changes can also be made by remote operators using WSOS or SCADA systems. If a WSOSoperator changes settings, the local operator will see the page title flash to indicate changes arepending. When any user puts their changes into service all pending changes, including thosemade by other users, go into service.

9.8 Overcurrent ProtectionThe Control And Protection Module (CAPM) continually samples the current flowing in thesecondaries of the current transformers. These samples are digitally processed by the CAPM tomonitor line current for the purposes of overcurrent protection. The phase currents are summeddigitally to give the earth current for the purpose of earth fault protection. Digital filteringalgorithms are applied to line currents to minimise transient overreach.The three current transformer currents are also summed as analogue signals to give the earth(or spill) current. These are sampled and digitally processed for the purposes of sensitive earthfault protection (SEF). A low pass filter on the spill current reduces sensitivity to harmonicsabove 60 Hz, reducing SEF sensitivity to transformer in-rush and other harmonic interference.If any of these signals (phase, earth or SEF) exceed the relevant Setting Current (phase, earth orSEF) then the relay Picks Up. Definite Time, Inverse Time and Instantaneous Protection are used to trip the recloser afterpickup:

Definite Time is a protection function that can be set by the user and it causes atrip at a fixed time after pickup. In the case of Definite Time the timing sequencestarts immediately after pickup.

Inverse time is a protection function in which the curve has an inverse timecharacteristic. Refer Section 9.9 (page 36).

Instantaneous Protection is an additional trip element that will trip the recloser ifthe line current exceeds the Instantaneous Multiplier by the setting current.

In the case of Inverse Time and Instantaneous Protection the timing sequence initiates when thesignal exceeds the Threshold Current. The Threshold Current is calculated from the settingcurrent and Threshold Multiplier. Refer Section 9.9.2 (page 39). If the current falls below 90% ofthe setting current for longer than the Fault Reset Time then that particular protectionelements timing sequence is cancelled and re-initialised. When all the protection elements havereset the peak currents on the faulted elements are logged.The setting currents are set once for all trips in a sequence but other protection parameters(eg. inverse curve type, multipliers and Reclose times) are set separately for each trip in areclose sequence. This allows, for example, Instantaneous Protection on the first trip in asequence and inverse time protection on subsequent trips in the sequence.

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To do this, two separate protection setting pages for each trip in a sequence are provided. Onepage applies to phase protection and the other to earth protection. These pages are shown inAppendix E (page 129).The operation of the different protection types is detailed below.

9.9 Inverse Time ProtectionA variety of inverse time curves are available which cause the recloser to trip faster as the currentrises higher. They are available on phase and earth with separate setting currents.Inverse time curves are implemented in software in the following way. The line current ismonitored after pickup. When it rises above the Threshold Current, the Time To Trip iscalculated and the timing starts. This calculation is repeated every few milliseconds in responseto changing line currents. When the remaining Time To Trip reaches zero, the trip request isissued. If the current falls below the Threshold Current the timing stops but the protectiondoes not reset. This means the relay will never trip at currents below the Threshold Currentunder inverse time protection.The parameters that control inverse time protection are:

Time Multiplier.

Additional Time.

Instantaneous Trip Element.

Minimum Time.

Maximum Time.

Threshold Multiplier.

Inverse Curve Type.

Setting Current.The Inverse Curve type is set independently for each trip. Refer Section 9.9.1 (page 38).The Setting Current is set for phase, earth or SEF. Refer Section 9.8 (page 35).

Time Multiplier: Set independently for each trip.Multiplies the Time To Trip. Refer Figure 8.

Figure 8: Time multiplier, effects on theinverse curve

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Additional Time: Set independently for eachtrip, sets an Additional Time To Trip which isadded to the inverse curve tripping time. ReferFigure 9.

Figure 9: Additional time, effects on theinverse curve

An Instantaneous Trip element can beapplied which will trip the recloser if thecurrent rises above a user set multiple of thephase or earth setting currents. If theInstantaneous Multiplier is set below theThreshold Current Multiplier then anInstantaneous Trip will only occur after the linecurrent exceeds the Threshold Current. ReferFigure 10.

Figure 10: Instantaneous, effects on theinverse curve

Minimum Time: Set independently for eachtrip, sets the Minimum Time To Trip. ReferFigure 11.

Figure 11: Minimum time, effects on theinverse curve

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Maximum Time: Sets the Maximum Time ToTrip if the time exceeds the preset limit. Refer Figure 12.

Figure 12: Maximum time, effects on theinverse curve

Threshold Multiplier: The Threshold Multiplieris used to prevent tripping if the line current isbelow the Threshold Current. The ThresholdCurrent is the setting current multiplied by theThreshold Multiplier. Refer Figure 13.

Figure 13: Threshold element, effects onthe inverse curve

9.9.1 Protection CurvesIn total there are 48 inverse protection curves stored in the controllers non-volatile memory.The selection of curves available are defined in the following Appendices:

3 Standard IEC255 curves are defined in Appendix A- IEC255 Inverse TimeProtection Tables (page 109).

3 Standard IEEE Std C37.112 curves are defined in Appendix B- IEEE InverseTime Protection Tables (page 111).

42 non-standard Curves are defined in Appendix C (page 113).Any one of the 48 curves can be selected for the phase and earth protection trips 1 to 4.Note: When instantaneous only protection parameters are selected, Minimum Time To Trip andthe Threshold multipliers apply but the Additional and Maximum times to trip do not.

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9.9.2 Interactions between curve parametersThis section describes some of the interactions that can occur between the user selectableinverse curve parameters. In order to understand the interactions between the curve settings it isimportant to know the way the curves are constructed. The following sequence shows the order in which the curve settings are applied:

Curve selected.

Time multiplier.

Additional Time.

Instantaneous element.

Maximum Time.

Threshold Current.

Minimum Time.

Figure 14 is an example of aprotection curve modified by theinstantaneous element andmaximum, minimum times.

Figure 14: Protection curve modified by minimum,maximum times and instantaneous element

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Figure 15 is an example of usingMaximum Time, Inst

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