Protection System Requirements for the High Voltage Network

Engineering Standard Electrical

Engi

neer

ing

Stan

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EP 19 00 00 02 SP

PROTECTION SYSTEM REQUIREMENTS FOR THE HIGH

VOLTAGE NETWORK Version 4.0

Issued May 2010

Owner: Chief Engineer Electrical

Approved by:

Wilfred Leung Chief Engineer Electrical

Authorised by:

Wilfred Leung Chief Engineer Electrical

Disclaimer This document was prepared for use on the RailCorp Network only. RailCorp makes no warranties, express or implied, that compliance with the contents of this document shall be sufficient to ensure safe systems or work or operation. It is the document user’s sole responsibility to ensure that the copy of the document it is viewing is the current version of the document as in use by RailCorp. RailCorp accepts no liability whatsoever in relation to the use of this document by any party, and RailCorp excludes any liability which arises in any manner by the use of this document. Copyright The information in this document is protected by Copyright and no part of this document may be reproduced, altered, stored or transmitted by any person without the prior consent of RailCorp.

RailCorp Engineering Standard — Electrical Protection System Requirements for the High Voltage Network EP 19 00 00 02 SP

© RailCorp Page 2 of 60 Issued May 2010 UNCONTROLLED WHEN PRINTED Version 4.0

Document control

Version Date Summary of change June 2007 Last Technical Review

4.0 May 2010 Application of TMA 400 format



Contents

1 Introduction .............................................................................................................................6 2 Normative References ............................................................................................................6

2.1 International Standards..............................................................................................6 2.2 Australian Standards .................................................................................................6 2.3 RailCorp Documents..................................................................................................6 2.4 Industry Publications..................................................................................................7

3 Definitions and Abbreviations ...............................................................................................7 4 General Protection Philosophy .............................................................................................8

4.1 General ......................................................................................................................8 4.2 Protection Settings.....................................................................................................8 4.3 Grading ......................................................................................................................8

5 Specific Protection Equipment Requirements.....................................................................8 5.1 Protection Equipment Design Principles - All New HV Switchgear...........................8 5.2 Interfacing New Protection Schemes With Existing Equipment ................................9

5.2.1 Multiple Use of Current Transformers ........................................................9 5.2.2 Trip Circuit Supervision ..............................................................................9 5.2.3 Breaker Fail ................................................................................................9 5.2.4 Inter-trip ....................................................................................................10

5.3 Current Transformers (CT) ......................................................................................10 5.3.1 General Requirements .............................................................................10 5.3.2 Additional Requirements for CT’s with a Rated Secondary

Current of 1 Amp. .....................................................................................10 5.3.3 Multiple Ratio Current Transformers ........................................................11 5.3.4 Protection Current Transformers..............................................................11 5.3.5 Measurement Current Transformers........................................................11 5.3.6 Current Transformer Secondary Wiring ...................................................11

5.4 Voltage Transformers ..............................................................................................12 5.4.1 General Requirements .............................................................................12 5.4.2 Voltage Transformer Secondary Wiring ...................................................12 5.4.3 Voltage Transformer Alarms ....................................................................13 5.4.4 Voltage Transformer Supply to Protection Relays ...................................13

5.5 Auxiliary Supply (DC)...............................................................................................13 5.5.1 General Requirements .............................................................................13 5.5.2 Requirement for Two battery Systems.....................................................13

5.6 Protection Relays.....................................................................................................14 5.7 Close Inhibit .............................................................................................................14 5.8 Protection Alarms ....................................................................................................14 5.9 Inter-Trip Arrangements...........................................................................................14

5.9.1 Preferred Technology...............................................................................14 5.9.2 Fibre Optic Pilots ......................................................................................15 5.9.3 Copper Pilots............................................................................................15

5.10 Integrated Support System......................................................................................15 6 Specific Equipment Applications ........................................................................................15



6.1 33kV & 66kV Feeders..............................................................................................15 6.1.1 Standard Protection Schemes .................................................................15 6.1.2 Primary Protection....................................................................................16 6.1.3 Backup protection.....................................................................................16 6.1.4 Circuit Breaker Fail Scheme ....................................................................16 6.1.5 Location of Current Transformers ............................................................16 6.1.6 Metering Requirements............................................................................16

6.2 11kV feeders............................................................................................................17 6.2.1 Standard Protection Schemes .................................................................17 6.2.2 Primary Protection....................................................................................17 6.2.3 Backup protection.....................................................................................17 6.2.4 Circuit Breaker Fail Scheme ....................................................................18 6.2.5 Location of Current Transformers ............................................................18 6.2.6 Metering Requirements............................................................................18

6.3 High Voltage Busbars & Bus-Tie Cables.................................................................18 6.3.1 Primary Protection for Busbars ................................................................18 6.3.2 Primary Protection for Bus-tie Cables ......................................................19 6.3.3 Backup Protection ....................................................................................19 6.3.4 Location of Current Transformers ............................................................19

6.4 Rectifier Transformer and Power Cubicle................................................................19 6.4.1 Primary Protection....................................................................................19 6.4.2 Backup Protection ....................................................................................20 6.4.3 Circuit Breaker Fail Scheme ....................................................................20 6.4.4 Protection Interface Requirements...........................................................20

6.5 System Transformers ..............................................................................................20 6.5.1 Standard Protection Schemes .................................................................20 6.5.2 Primary Protection....................................................................................20 6.5.3 Backup Protection ....................................................................................20 6.5.4 Circuit Breaker Fail Scheme ....................................................................20 6.5.5 Neutral Leakage .......................................................................................21 6.5.6 Buchholz Relay ........................................................................................21 6.5.7 Location of Current Transformers ............................................................21

6.6 11kV/415V Transformers.........................................................................................21 6.6.1 Transformers Supplied from Ring Main Units ..........................................21 6.6.2 Transformers Supplied from SCADA Controlled ACCB’s ........................21 6.6.3 Standard Protection Schemes .................................................................21 6.6.4 Primary Protection....................................................................................22 6.6.5 Backup Protection ....................................................................................22 6.6.6 Circuit Breaker Fail Scheme ....................................................................22

6.7 Documentation Requirements .................................................................................22 6.7.1 Concept Design Documentation ..............................................................22 6.7.2 Detail Design Documentation...................................................................23 6.7.3 Commissioning Documentation ...............................................................23

Appendix A Protection Relays ..................................................................................................24 Approved Protection Relays....................................................................................................24 Location of Protection Relays .................................................................................................24



Appendix B ACCB Trip Coils - Standard Equipment Connection .........................................26 Appendix C Two Battery Systems (125V DC) - Standard Protection Equipment

Connection .............................................................................................................27 Appendix D Interfacing With Existing Pilot Wire Schemes....................................................28 Appendix E Current Transformers (33kV & 66kV)...................................................................29

Rectifier Instantaneous Overcurrent & Earth Fault .................................................................29 Overcurrent and Earth Fault ...................................................................................................29 Pilot Wire Schemes.................................................................................................................30 Bus-Zone Schemes & Transformer Differential ......................................................................30

Appendix F Current Transformers for 11kV Switchgear........................................................31 Appendix G Protection Relay Identification.............................................................................32 Appendix H Standard Test Block Wiring & Input/Output Relay Configuration....................33 Appendix I Voltage and Current Transducers........................................................................46 Appendix J Pilot Wire Schemes ...............................................................................................47 Appendix K Auto Re-close on High Voltage Feeders .............................................................48 Appendix L Protection SCADA Alarms....................................................................................49 Appendix M Implementation Of SCADA Alarms & Control ....................................................51 Appendix N Typical ACCB Auxiliary Supply Arrangement ....................................................52 Appendix O Protection Relay Labelling Guidelines................................................................54 Appendix P Standard Current Transformer Configurations ..................................................57 Appendix Q Protection Non-Compliances Particular to the ECRL Project...........................60

11kV Protection.......................................................................................................................60 33kV Protection.......................................................................................................................60



1 Introduction This document covers the Protection System requirements for the RailCorp High Voltage AC Network for 33kV, 66kV and 132kV system voltages. The scope of this publication does not currently include specific protection scheme requirements for the high voltage AC network at 2kV system voltage. This will be incorporated in a future revision of this specification.

This document does not include protection requirements for the 1500V DC system.

The Specific Protection Equipment Requirements (Section 5 and associated Appendix) are common requirements for the entire high voltage network.

These protection requirements cover general design principles for protection schemes, as well as requirements relating specifically to the protection equipment. They do not include equipment used for detection and measurement of non-electrical protection parameters (such as oil and gas sudden pressure change, fibre optic temperature measurement), other than to specify necessary interface details.

The correct design, implementation and management of the overall protection system are critical to the safe and reliable operation of the RailCorp power system. As such, all design processes for the protection system must follow the RailCorp Engineering Design Management Procedures.

All new installations, modified and refurbished existing installations must comply with the requirements in this document.

High voltage protection systems existing at the date of release of this document are not affected by the requirements of this document.

2 Normative References The following documents are either referenced in this standard or can provide further information. The edition is current at the time of publication of this document.

2.1 International Standards IEEE C.37.2 - 1996 Standard electrical power system device function numbers and contact designations.

2.2 Australian Standards AS1102-1996 Graphical symbols for diagrams. Switchgear, control gear and protective devices. AS 1675 - 1986 Current Transformers – Measurement and Protection AS 2067 - 1984 Switchgear assemblies and ancillary equipment for alternating voltages above 1 kV AS 1243 - 1982 Voltage Transformers for Measurement and Protection

2.3 RailCorp Documents EP 00 00 00 01 TI RAC Electrical system General Description EP 00 00 00 12 SP Electrical Power Equipment – Integrated Support Requirements EP 00 00 00 13 SP Electrical Power Equipment – Design Ranges of Ambient Conditions



EP 00 00 00 15 SP Common requirements for Electrical Power Equipment EP 00 00 00 00 MP Electric Power Technical Maintenance Plan EP 03 02 00 01 SP Controls and Protection for Rectification Equipment EP 99 00 00 02 SP System Commissioning tests EP 01 00 00 01 SP 33kV AC Indoor Switchgear – Non-Withdrawable TS 34 10 03 01 SP Design & Installation – Tunnel Fire safety – New Passenger Railway Tunnels ED0001 P –ED0021 P inclusive Engineering Design Management Procedures

2.4 Industry Publications Network Protection & Automation Guide (AREVA) (previously titled: Protective Relays Application Guide) Alstom/Areva Protection Relay Application Guides

3 Definitions and Abbreviations ACCB Alternating current circuit breaker

DC Auxiliary Supply Supply for the operation of electronic protection relays, energisation of multi-trip relay coils, energisation of HV ACCB trip and close coils and general control circuit operations. Nominally 125V DC or 48V DC.

CT(s) Current Transformer(s)

DC Direct Current

Dedicated Pilot Cable A communication cable that is used only for the control, indication and pilot wire functions between two substations. The cable is continuous between substations.

FAT Factory acceptance test

IT Inter-trip

Low Voltage Compartment The compartment on the high voltage switchgear where the protection relays, control equipment and wiring is installed. The compartment is usually accessed by a hinged door and does not require any isolation or operation of the switchgear for safe access.

MTA Protection relay used for the multi-tripping of ACCB’s. This is a automatically reset relay with a hand reset flag.

MTM Protection relay used for the multi-tripping of ACCB’s. This is a manually reset relay with a hand reset flag.

Substation The following are locations within the RailCorp electrical network which are classified as system substations for the purpose of this document.

• Any location that includes a high voltage circuit breaker. • Traction substation • High voltage switching station • High voltage switchroom (except 2kV)

2kV locations, pole top and other distribution substations that use HV fuses for protection are not classed as system substations.



RTU Remote Terminal Unit (Interface to SCADA system)

SCADA Supervisory Control and Data Acquisition system.

Supervisory A connection to the Electrical Operating Centre to allow the remote operation of equipment and provision for remote monitoring of status and alarms using a SCADA system.

4 General Protection Philosophy

4.1 General In designing the protection schemes for RailCorp’s high voltage network, the following general principles shall be applied:

• All high voltage faults shall be detected and able to be cleared by two independent sets of protection (primary and backup). Either may be circuit breakers or fuses.

• The primary and backup protection schemes shall be independent. All HV circuit breakers shall be equipped with dual trip coils.

• Where primary and backup protection is installed in the same substation, that substation shall have two battery systems. Some substations are exempt from this requirement. This exemption is based on risk exposure considering safety, operational impact, economic and environmental considerations.

• The thermal limit current of the CT’s shall not constrain the rating of associated power system elements.

• Primary protection shall be implemented using unit schemes wherever practical. • The protection schemes shall be designed to eliminate or manage “blind spots”.

4.2 Protection Settings • The protection shall be set to operate at not more than 2/3 of the minimum phase

to phase fault and not more than 2/3 of the minimum earth fault. • The overcurrent protection settings shall, as far as practicable, be at least 1.5 times

the maximum load current. • Fault clearing times shall be minimised.

4.3 Grading • The protection shall be graded to ensure that the fault is cleared by the protection

closest to the fault, and the area of interruption is minimised. • A 0.3 second grading margin shall be provided for protection ‘in series’ except that

breaker fail timers shall be 0.2 second. • Relay settings shall be, as far as practicable, at least 1.5 times the highest

downstream setting.

5 Specific Protection Equipment Requirements

5.1 Protection Equipment Design Principles - All New HV Switchgear To ensure the independence and integrity of protection schemes the following principles shall apply:



• Protection current transformers shall be connected to protection equipment only. Approved transducers used for interfacing with the SCADA are to be regarded as protection equipment. Appendix I lists approved transducers.

• Primary and backup protection schemes shall be implemented using separate relays.

• Where the primary and backup scheme trip the same HV circuit breaker, the following shall apply:

– The primary and backup schemes shall use separate trip coils, one trip coil for the primary scheme the second trip coil for the backup scheme. Refer to Appendix B for standard trip coil arrangements and Appendix N for typical HV switchboard arrangements.

– The backup scheme (protection relay, trip coil control and supply) shall have a separate auxiliary supply.

• Where two DC auxiliary supplies are required (see Section 5.5) the primary protection scheme is to be supplied by battery A and the backup protection scheme supplied by battery B.

– SCADA monitored trip circuit supply supervision with local indication shall be provided for all tripping circuits.

– The auxiliary supply for each bus-zone protection scheme (protection and multi-trip relays) shall have its auxiliary supply from a dedicated circuit originating at the distribution board. Fuse protection and monitoring shall be provided with the monitoring relay connected to the SCADA system.

– Individual protection schemes to be connected to dedicated current transformers.

5.2 Interfacing New Protection Schemes With Existing Equipment

5.2.1 Multiple Use of Current Transformers It is acceptable to have more than one protection scheme (maximum two schemes) connected to the same set of CT’s as long as the following applies:

• It is not economically feasible to install additional CT’s (eg. Circuit breaker would have to be replaced; additional post type CT’s would be required.)

• The protection schemes are not the primary and backup protection for the same equipment.

• A failure of the CT’s will not result in a piece of equipment having no protection due to an existing compromise in the protection system.

• The output of the current transformers shall be sufficient for the burden of all the connected protection schemes and associated equipment to ensure each scheme operates as required up to the available fault level.

5.2.2 Trip Circuit Supervision Where a new protection scheme is interfacing with existing switchgear that does not have trip circuit supervision (TCS), TCS shall be implemented either as a function of the protection relay (if available) or installation of a dedicated TCS relay (refer Appendix A).

5.2.3 Breaker Fail When new protection relays that have breaker fail functionality are installed in an existing substation, the breaker fail detection shall result in the energising of a multi trip relay. The multi-trip relay shall trip all the associated ACCB’s on the busbar.



5.2.4 Inter-trip If the breaker fail function is associated with a feeder that does not have a dedicated ACCB, then it is acceptable to implement an inter-trip by destabilising the pilot wire schemes of feeders that are a possible source of fault current. When destabilising the pilot wire schemes this must be implemented at the pilot wire relay.

5.3 Current Transformers (CT)

5.3.1 General Requirements All protection and metering CT’s shall comply with AS 1675.

The CT shall be easily replaceable and shall be installed with polarity markings assuming supply from the bus in all cases. All secondary leads shall be terminated in individual links in the appropriate compartment where the CT is installed and the earth point formed by using a proprietary cross connection for the links being used. The CT’s shall be earthed at one point. This single point earth is to be within the applicable LV compartment.

CT’s shall be rigidly clamped to prevent movement under short circuit conditions. They shall be provided with rating plates and terminal markings as specified in AS 1675. The rating plates shall be mounted in such a manner that they are visible, and the secondary terminals shall be readily accessible. Duplicate rating plates shall be mounted in the instrument compartment with connection diagram.

The majority of existing CT’s installed in the RailCorp’s system have a rated secondary current of 5A. With the installation of GIS switchgear, the reduced space available for CT’s has resulted in the necessity to install CT’s with a rated secondary current of 1A.

CT’s shall safely withstand the mechanical and thermal stresses set up by a short circuit equal to the full short circuit rating of the switchgear. CT’s shall have a minimum thermal limit current at least 1.5 times rated current unless modified by the RFT for the specific location.

See Section 6.1.5 for CT location requirements for 33 & 66kV Feeders.

See Section 6.2.5 for CT location requirements for 11kV Feeders.

See Section 6.3.4 for CT location requirements for HV Busbars and Bus-Ties.

See Section 6.5.7 for CT location requirements for System Transformers.

5.3.2 Additional Requirements for CT’s with a Rated Secondary Current of 1 Amp. If it is proposed to use CT’s with a rated secondary current of 1A, then the following issues shall be complied with.

• Provision of a detailed design solution for the secondary wiring under system fault conditions. This design solution must address the voltage withstand ratings of all connected equipment as the secondary voltages developed are five times larger than if the CT’s have the preferred value of 5A.

• A complete integrated system support analysis of using the non-standard protection equipment must be economically justified. See 5.10 Integrated Support System for details.



5.3.3 Multiple Ratio Current Transformers Where multiple ratio CT’s are used, the links associated with changing the CT ratio shall be fit for purpose.

The CT terminals shall be clearly marked to enable correct changing of the ratio. The associated rating plate shall also be marked with the information to enable correct changing of the ratio.

5.3.4 Protection Current Transformers Protection CT shall be of a class entirely suitable for the connected equipment so as to give correct operation under all service and fault conditions.

The following composite error shall apply:

• Differential schemes – 2.5% • Overcurrent & earth fault – 10%

The rated short-time is 3 seconds.

The rated short time current shall have a minimum rating equal to the short time withstand current of the associated switchboard or circuit breaker.

Appendix B has a table listing the typical ratio and designation of current transformers, which are preferred for use in the RailCorp electrical network.

5.3.5 Measurement Current Transformers Measurement CT’s shall be of a class entirely suitable for the application as specified in AS 1675.

As a general guide the following are typical class of accuracy used in the RailCorp network:

• 0.5M for general tariff metering such as supplies to shops, workshops etc. • 2M for general measurement such as transducers and ammeters.

The measurement current transformers shall have the same ratio and thermal current limit as the associated protection CT’s on the circuit.

5.3.6 Current Transformer Secondary Wiring All CT secondary wiring shall be provided with test links at the marshalling strip within the respective low voltage compartment. The test links shall be Weidmuller SAKC10.

The wiring shall be connected to the associated protection relay (or meter) via a test block that allows isolation of the relay / metering and short-circuiting of the current transformer secondary. If the relay test blocks are not integral with the relay enclosure, test blocks of the type Areva MMLG01 shall be provided.

The test blocks shall be located adjacent to the respective protection relay.

The current transformer secondary wiring shall be coloured as detailed below:

• A∅ : red • B∅ : white • C∅ : blue • Neutral : black



The wiring shall be a minimum size of 2.5mm2 and have an insulation rating of 0.6/1 kV. Where 2.5mm2 wiring is used it shall have a stranding of 50/0.25mm. All wiring connections to CT’s and to protection relays shall be made using double grip ring type pre-insulated crimp lugs.

Wiring identification shall be in accordance with AS2067. Refer to EP 00 00 00 15 SP Common Requirements for Electrical Power Equipment, for details of cable identification requirements.

5.4 Voltage Transformers

5.4.1 General Requirements Voltage transformers shall be provided for all three phases and can either be a 3 phase voltage transformer or 3 single phase voltage transformers.

Voltage transformers shall be manufactured and tested in accordance with AS 1243. They shall have a rated primary voltage as specified by the switchgear and have two secondary windings with a voltage factor of 1.9 for 30 seconds as follows:

PERFORMANCE CATEGORY

RATED VOLTAGE

ACCURACY CLASS

RATED BURDEN

A 110 V 5 P 8 mS B (residual) 110/√3 V 3 R 8 mS

Table 1 - Voltage Transformer Specifications

The neutral point of the star connected primary shall be earthed. The neutral point of the star connected secondary winding shall be brought out and connected to suitably insulated terminals located in the LV compartment and earthed.

The voltage transformers shall be protected by suitably rated circuit breakers connected in the low voltage circuit as close as possible to the transformer terminals.

High voltage fuse protection of VT’s is not mandatory and is only required where necessitated by equipment design.

The requirement for a residual winding is dependent on the type of protection relays to be used.

For maintenance, and for the commissioning of protection relays, it shall be possible to simulate the voltage conditions that would occur during earth faults and the supplier shall explain how this is achieved. A typical way to achieve this is to remove the high-voltage fuse in any one phase and earth that phase of the voltage transformer.

5.4.2 Voltage Transformer Secondary Wiring The voltage transformer secondary wiring shall be coloured as per the current transformer wiring with the exception of any open delta wiring, which shall be purple.

Terminal blocks for VT secondary wiring shall provide 4mm sockets for the connection of test equipment.



5.4.3 Voltage Transformer Alarms A three phase, phase failure relay shall be connected to the star connected secondary winding of the voltage transformer. The phase failure relay shall provide a normally closed 'VOLTAGE TRANSFORMER FAIL' alarm contact as well as visual indication. The relay shall detect both under-voltage and negative phase sequence voltage unbalance on the load side of the main circuit breaker.

5.4.4 Voltage Transformer Supply to Protection Relays The VT supply to protection relays shall be via a dedicated circuit breaker for each protection relay. The circuit breaker shall have a voltage free auxiliary contact which is connected to the SCADA system to give an “FEEDER XXX DIRECTIONAL VOLTAGE FAIL' alarm.

5.5 Auxiliary Supply (DC)

5.5.1 General Requirements The following are general requirements for the arrangement of auxiliary supplies to protection circuits and ACCB control.

All ACCB’s shall be individually supplied from the 125V DC or 48V DC distribution board(s). The majority of RailCorp locations have an auxiliary supply of 125V DC, other locations have a supply of 48V DC.

In each ACCB, distinct control circuits and equipment shall be individually fused. The fuses shall be sized to ensure there is discrimination.

The following is a list of typical ACCB circuits and equipment that would be individually protected by fuses.

• electronic protection relays • trip coil circuits • close control circuit • motor/spring charge circuits • alarm & indication circuits • DC/DC power supplies (eg. ILIS power supply, transducer supplies)

5.5.2 Requirement for Two battery Systems To ensure integrity of the RailCorp electrical network is maintained when an auxiliary supply fails, strategic substations are required to have two independent substation battery systems.

The criteria determining this requirement are:

• Connectivity of the substation (4 or more high voltage feeders) within the RailCorp electrical network.

• Maximum high voltage fault level and the margin to the rated short-time withstand current capacity of the switchgear installed at the substation.

• Criticality of the substation within the rail system. (eg. Main supply substation for city circle, rail tunnel, rail junction, last traction substation on a radial rail line).

• Where primary and backup protection is installed in the same substation, that substation shall have two battery systems. Some substations are exempt from this requirement. This exemption is based on risk exposure considering safety, operational impact, economic and environmental considerations.



• Complexity of the protection schemes and any resulting compromises in the protection coordination.

The associated main distribution boards of the battery systems are to be capable of being paralleled.

Refer to Section 5.1 and Appendix C for specific requirements relating to protection schemes when there are two auxiliary supplies at a substation.

5.6 Protection Relays All protection relays shall be flush mount and withdrawable. The auxiliary supply to the protection relays shall be 125V DC or 48V DC as determined by the existing substation battery or specified in the Substation design.

Appendix A has a table listing the protection relays which are currently approved for use in the RailCorp electrical network.

When specifying the type of protection relay to be used consideration must be given to ensure adequate integrated system support including availability of system spares. See 5.3.2 Additional Requirements for CT’s with a Rated Secondary Current of 1 Amp.

Alternatives to relays specified in Appendix A must be approved by the Chief Engineer, Electrical Systems.

5.7 Close Inhibit Where a protection operation results in an MTM relay being energised, the MTM relay shall have normally closed contacts in the closing circuit of all the HV ACCB’s that were tripped by the MTM. This is to prevent the ACCB’s from being closed. This is applicable for all protection schemes.

System transformers and 11kV/415V transformers shall have a close inhibit contact in both the primary and secondary ACCB closing circuits where fitted.

5.8 Protection Alarms Every operation of a protection relay shall result in an individual alarm being sent to the SCADA system and provide a local indication. The alarm shall enable the Electrical System Operators to accurately identify the protection scheme that has operated.

If a protection relay has more than one function (eg A∅ and C∅ overcurrent elements), then where practical each function shall have a separate alarm output.

Refer to Appendix L for a detailed listing of SCADA alarms.

5.9 Inter-Trip Arrangements

5.9.1 Preferred Technology Optical fibre pilots are preferred for inter-tripping.

Refer to Appendix A for protection relays currently preferred for use in the RailCorp Electrical Network for type of inter-trip relay.



5.9.2 Fibre Optic Pilots Where fibre optic pilots are available, the inter-tripping may be achieved utilising pilot wire relays that have inter-tripping as a function of the relay.

5.9.3 Copper Pilots Where inter-trip arrangements are required for a feeder, it is preferred the inter-trip scheme is implemented using a dedicated pair of pilots for the scheme.

If there are no spare pilots in the existing pilot cable, the inter-trip may be achieved by manipulating the feeder pilot wire scheme.

A minimum of 15kV isolation shall be provided to avoid transfer of voltages across the pilots. This may be achieved by using an inter-trip relay that provides isolation at either end of the scheme.

5.10 Integrated Support System An Integrated Support System exists for protection equipment. This current system is based on 5 Amp CT’s and protection relays nominated in Appendix A. An economically justified integrated support analysis is required for any proposal to use non preferred schemes, relays or CT’s. The analysis shall include relevant requirements of EP 00 00 00 12 SP and take account of the following:

• Test and support equipment • Relay programming software • Staff training • Spares analysis and procurement • Maintenance requirements analysis • Operation and maintenance manuals

6 Specific Equipment Applications

6.1 33kV & 66kV Feeders

6.1.1 Standard Protection Schemes The following schemes shall be provided for the protection of 33kV and 66kV feeders:

RailCorp network feeder Bulk Supply Feeder Primary Protection

Pilot wire Directional over-current and earth fault (looking towards supply point) and Pilot wire or Distance protection (zone 1, last 20% Zone 2) at the supply end

Backup Protection

over-current and earth fault (may be directional if required by system configuration to achieve discrimination) and circuit breaker fail

In accordance with the other Network Operator’s policy

Table 2 - 33kV & 66kV Feeder Protection Schemes



6.1.2 Primary Protection If the pilot circuit is not run via a dedicated pilot cable, an instantaneous over-current and earth fault check relay shall be provided in series with the trip from the pilot wire relay to prevent nuisance tripping of the feeder.

All pilot wire schemes shall include pilot circuit supervision. This may be implemented either as a function of the pilot wire relay or using dedicated pilot circuit supervision equipment.

6.1.3 Backup protection The unit protection on the feeder shall be backed up by an over-current and earth fault scheme. This scheme shall operate via a circuit breaker and current transformers that are not part of the primary scheme.

6.1.4 Circuit Breaker Fail Scheme The failure of a circuit breaker to open in response to a protection trip command shall be detected and the appropriate upstream circuit breaker(s) tripped. A time delay shall be provided to avoid nuisance tripping.

It is preferred that the feeder pilot wire relay provides this function. Where the pilot wire relay does not have this function an overcurrent and earth fault relay (with directional capabilities) shall be provided to implement the breaker fail scheme.

A contact from the pilot wire relay shall be connected to the overcurrent and earth fault relay, which will initiate an internal timer (nominally set to 0.2s). If the fault has not been cleared within this time all possible sources of supply shall their ACCB’s tripped. All ACCB’s on the same busbar section as the failed ACCB shall be tripped via a multi-trip relay.

Where the operation of a breaker fail scheme shall cause a Supply Point feeder to be not available, the associated protection relay(s) shall attempt to trip the ACCB via all available trip coils. The trip coils shall be connected to separate output contact/relays of the protection relay.

6.1.5 Location of Current Transformers It is preferred that the CT’s are located on the busbar side of the feeder circuit breakers.

However where this is not practicable, the current transformers for feeder protection may be located on the line side of the feeder circuit breaker. In this arrangement an inter-trip shall be provided to trip the feeder circuit breaker at the far end of the feeder whenever the local feeder circuit breaker is tripped. The far end circuit breaker is only required to trip if fault current is flowing through that circuit breaker.

Refer to Section 5.9 Inter-Trip Arrangements for further details on inter-tripping.

See Appendix J for typical Pilot Wire arrangements.

6.1.6 Metering Requirements Every feeder shall be provided with an ammeter and all bulk supply feeders shall be provided with kWh metering.

Details of the ammeter, metering and their connection are specified in the appropriate switchgear standard.



The requirements for 33kV indoor switchgear are detailed in EP 01 00 00 01 SP 33kV AC Indoor Switchgear – Non-Withdrawable.

6.2 11kV feeders

6.2.1 Standard Protection Schemes The 11kV network supplies a large variety of installations with varying degrees of operational criticality. These installations range from underground stations, major signal boxes to minor maintenance locations supplied from pole mounted transformers.

The criticality of the installation, accessibility of the 11kV feeder and the fault level determines the type of protection to be provided.

6.2.2 Primary Protection The following list details the requirement for the primary protection to be a pilot wire scheme.

• 11kV feeders supplying underground railway stations. • 11kV feeders supplying major signal boxes • 11kV feeders installed in tunnels • 11kV feeders supplying installations deemed to be operationally critical • 11kV feeders where it is time critical to clear the fault due to high fault levels or

bushfire hazards.

All pilot wire schemes shall include pilot circuit supervision. This can be implemented either as a function of the pilot wire relay or using dedicated pilot circuit supervision equipment.

Where the primary protection scheme is not required to be a pilot wire scheme, the feeder shall be protected with an over-current and earth fault scheme.

6.2.3 Backup protection The primary protection on the feeder shall be backed up by an over-current and earth fault scheme.

Where the primary protection is a pilot wire scheme, the backup over-current and earth fault scheme can be located on the same circuit breaker panel, however the scheme must operate via a separate protection relay and ACCB trip coil.

Where the primary protection is not a pilot wire scheme, the backup over-current and earth fault scheme shall operate via a circuit breaker and current transformers that are not part of the primary scheme.

Where the primary protection is an overcurrent and earth fault scheme and is located on a 11kV switchboard supplied directly from a transformer, a neutral leakage relay shall be used as backup protection for earth faults.

The transformer primary overcurrent protection may be used to backup feeder overcurrent protection. This is subject to the transformer overcurrent settings being suitable.



6.2.4 Circuit Breaker Fail Scheme The failure of a circuit breaker to open in response to a protection trip command shall be detected and all ACCB’s on the same busbar section as the failed ACCB shall be tripped via a multi-trip relay. The multi-trip relay used to implement this may be the bus-zone multi-trip relay.

If the feeders are protected by a pilot wire scheme then the appropriate upstream circuit breaker(s) shall be tripped. A time delay (0.2s) shall be provided to avoid nuisance tripping.

It is preferred that the protection relays provide this function.

6.2.5 Location of Current Transformers It is preferred that the CT’s are located on the busbar side of the feeder circuit breakers.

However where this is not practicable, the current transformers for feeder protection can be located on the line side of the feeder circuit breaker. This is subject to RailCorp approval.

6.2.6 Metering Requirements Every feeder shall be provided with an ammeter and all feeders that are a dedicated supply to commercial premises (eg, train maintenance centres) shall be provided with kWh metering.

Details of the ammeter, metering and their connection are specified in the appropriate switchgear standard.

6.3 High Voltage Busbars & Bus-Tie Cables

6.3.1 Primary Protection for Busbars All 33kV and 66kV indoor switchgear shall have bus zone protection as the primary protection for the busbar.

The requirement for 11kV indoor switchgear to have bus zone protection depends whether the location is a:

• strategic location • location with high fault levels • location where there is more than one busbar section

The traditional high impedance bus-zone protection scheme using CT’s is an approved RailCorp scheme. A fault detection scheme that has been type tested and is an integral system within the switchgear may be offered for consideration by RailCorp and if approved will be the preferred scheme.

Strategically important outdoor 33kV and 66kV busbars shall also have high impedance bus zone protection as the primary protection. The criteria for this decision will be provided in a later version of this document.

Separate schemes shall be provided for each section of the busbar. All ACCB’s on the associated bus-section shall be tripped. Close inhibit shall also be implemented, refer to Section 5.7



The tripping of circuit breakers on an indoor switchboard shall be via a MTM relay. The tripping of circuit breakers on an outdoor busbar shall be via an MTA relay.

6.3.2 Primary Protection for Bus-tie Cables All bus-tie cables interconnecting 11kV, 33kV and 66kV indoor switchboards shall have high impedance bus zone protection as the primary protection.

The scheme shall be arranged to trip the circuit breakers at both ends of the tie cable via a manually reset multi-trip relay. Close inhibit shall also be implemented, refer to Section 5.7

6.3.3 Backup Protection The backup protection for a busbar shall be upstream over-current and earth fault protection.

The backup protection for a bus-tie shall be upstream over-current and earth fault protection except where the switchboard directly interfaces with a Supply Authority. Where the switchboard interfaces with a Supply Authority the bus-tie cables shall have a duplicate high impedance protection scheme as the backup protection. Refer to Appendix A for the type of relay to be used.

6.3.4 Location of Current Transformers The current transformers for protection of the busbar shall be located on the line side of all circuit breakers.

The current transformers for protection of the bus-tie cables shall be located on the busbar side of the tie circuit breaker.

Where the current transformers for the feeder, bus-tie, or transformer circuits are not located on the busbar side of the circuit breaker and the bus zone scheme is used to cover the blind spots between the circuit breakers and the CT’s, then the bus-zone scheme shall also initiate tripping of the circuit breakers at the far end of the feeder or tie cable, or on the other winding of the transformer.

6.4 Rectifier Transformer and Power Cubicle

6.4.1 Primary Protection The primary protection for the rectifier transformer and power cubicle shall be provided by an A∅ and C∅ instantaneous overcurrent and instantaneous earth fault relay.

If the transformer is cable connected (terminals/bushings are not exposed), the circuit breaker shall be tripped via a MTM relay for earth faults.

The overcurrent elements are required to operate when a fault on the +1500V DC busbar (when there is a 400V arc) is detected.

A current transducer shall be provided in the B∅ protection circuit. The transducer output shall be connected to the panel ammeter and analogue input to SCADA.

See EP 03 02 00 01 SP – Controls and Protection for Rectification Equipment, for further detailed information on these requirements.



6.4.2 Backup Protection The backup protection scheme for the rectifier transformer and power cubicle shall be provided by a separate protection scheme, which is located in the same substation. The protection relay shall be an A∅, B∅ and C∅ instantaneous overcurrent and instantaneous earth fault relay.

If the transformer is cable connected, the circuit breaker shall be tripped via a MTM relay for earth faults.

6.4.3 Circuit Breaker Fail Scheme The failure of the circuit breaker to open in response to a protection trip command shall be detected and the associated bus-zone MTM relay shall be energised. A time delay of 0.2 seconds shall be provided to avoid nuisance tripping.

It is preferred that the protection relays provide this function

6.4.4 Protection Interface Requirements Refer to EP 03 02 00 01 SP – Controls and Protection for Rectification Equipment, for further detailed information on the protection interface requirements.

6.5 System Transformers

6.5.1 Standard Protection Schemes All 33kV and 66kV transformers 750MVA or greater in size shall have transformer differential as the primary protection and overcurrent and earth leakage as the backup protection. Oil filled transformers shall be fitted with a buchholz oil & gas relay.

6.5.2 Primary Protection The transformer differential scheme shall be arranged to trip both the primary and secondary circuit breakers.

The tripping of the circuit breakers shall be via a multi-trip relay. If the transformer is cable connected (terminals/bushings not exposed) the multi-trip relay shall be a manually reset relay.

6.5.3 Backup Protection Overcurrent and earth fault shall be provided as the backup transformer protection.

The tripping of the circuit breakers shall be via a multi-trip relay. If the transformer is cable connected (terminals/bushings not exposed) the multi-trip relay shall be a manually reset relay for earth faults and an automatically reset relay for overcurrent faults.

Three phase over current protection shall be provided on the high or low voltage side of the transformer as backup protection to the outgoing feeder overcurrent protection.

6.5.4 Circuit Breaker Fail Scheme The failure of a circuit breaker to open in response to a backup protection trip command shall be detected and the associated bus-zone MTM relay energised. A time delay of 0.2 seconds shall be provided to avoid nuisance tripping.



The three phase overcurrent protection relay on the same side of the transformer as the scheme being backed up shall provide this function.

6.5.5 Neutral Leakage Neutral leakage shall be provided as backup protection to feeder earth fault. The scheme shall trip both the primary and secondary circuit breaker of the transformer via an MTA relay.

6.5.6 Buchholz Relay A buchholz relay shall be provided in the oil line between the conservator and the main tank.

Operation of either the oil or gas element of the buchholz relay shall trip both the primary and secondary circuit breakers via a manually reset multi-trip relay.

Each element of the buchholz relay shall have voltage free alarm contacts, which are connected to the SCADA system.

6.5.7 Location of Current Transformers It is preferred that the current transformers for the differential protection are located on the busbar side of both the primary and secondary circuit breakers.

Where this is not practicable, it is acceptable that the current transformers for transformer protection be located on the transformer side of the transformer circuit breaker.

The current transformer for the neutral leakage protection shall be located on the neutral to earth connection of the transformer.

6.6 11kV/415V Transformers

6.6.1 Transformers Supplied from Ring Main Units All 11kV distribution transformers (200kVA and above up to 800kVA), that are supplied via an ACCB from a RMU shall be protected by a Merlin Gerin VIP300LL protection relay. An MMLG01 test block shall be fitted adjacent to the relay.

Transformers less then 200kVA shall be protected by fuses. The VIP300LL relay can not be used for transformers less then 200kVA as there may be insufficient magnetising current to meet the self powering requirements of the relay.

6.6.2 Transformers Supplied from SCADA Controlled ACCB’s

6.6.3 Standard Protection Schemes All 11kV transformers 750kVA or greater in size shall have transformer differential as the primary protection and overcurrent and earth leakage as the backup protection. Oil filled transformers shall be fitted with a buchholz oil & gas relay.

For transformers < 750kVA primary protection shall be overcurrent and earth leakage. Transformer differential schemes may be used on smaller transformers where required to ensure that the transformer protection grades over the LV protection.



6.6.4 Primary Protection The transformer differential scheme shall be arranged to trip both the primary and secondary circuit breakers.

The tripping of the circuit breakers shall be via a multi-trip relay. If the transformer is cable connected (terminals/bushings not exposed) the multi-trip relay shall be a MTM relay.

6.6.5 Backup Protection Overcurrent and earth fault shall be provided as the backup transformer protection.

The backup protection scheme is not required to detect faults on the LV winding of a distribution transformer or the LV cables.

The tripping of the circuit breakers shall be via a multi-trip relay. If the transformer is cable connected (terminals/bushings not exposed) the multi-trip relay shall be a MTM relay for earth faults and an MTA relay for overcurrent faults.

6.6.6 Circuit Breaker Fail Scheme The failure of a circuit breaker to open in response to a backup protection trip command shall be detected and the associated bus-zone MTM relay energised. A time delay of 0.2 seconds shall be provided to avoid nuisance tripping.

It is preferred that the protection relays provide this function.

6.7 Documentation Requirements There are three distinct stages for the submission of documentation related to the protection design and implementation for RailCorp to review.

a) The first stage is the concept design documentation.

b) The second stage is the submission of the detailed design documentation.

c) The third stage is the submission of all testing, commissioning and as-built documentation.

6.7.1 Concept Design Documentation The following documentation is to be submitted to RailCorp prior to the procurement of any equipment that is required to meet comply with this standard:

• Approved operating diagrams • Fault levels • Protection concept design. This document shall include:

– Diagrams detailing the functionality of the protection schemes – Text document outlining in detail the protection schemes. This document shall

include such details as: functional description of protection schemes, current transformer details, protection relay types, trip coil, SCADA alarms, analogue details, auxiliary battery details.

• Calculations (eg. CT knee-point voltage, VT burdens, fault levels) • High voltage equipment specifications



6.7.2 Detail Design Documentation The following documentation is required to be submitted to RailCorp prior to the approval of equipment manufacture.

• Schematic diagrams • Equipment arrangement / layout drawings • Equipment label schedule

6.7.3 Commissioning Documentation The following commissioning documentation is required to be submitted to RailCorp prior to the energisation of equipment.

• Equipment FAT test results • Primary injection test results • Secondary injection test results • Protection relay/scheme functionality checklists • Protection relay software setting files • Protection grading studies • Protection instructions • Equipment operating and maintenance manuals • As-built documentation (drawings, schedules etc) • Related test documentation to ensure the safe operation of the equipment (eg.

earthing test results)



Appendix A Protection Relays

Approved Protection Relays The following tables detail the requirements for protection relays when new switchboards are installed in the RailCorp electrical Network.

The tables detail the protection relays which are currently preferred for use in the RailCorp electrical network and when installing a new switchboard in an existing system whether the existing pilot wire relays are required to be replaced.

SCHEME EQUIPMENT RELAY TYPE Supply point feeder MHOB04,

MiCOM P521/P540, SIEMENS 7SD610 (mandatory if fibre optic available) Pilot Wire

RailCorp feeder MBCI02* or MiCOM P521/P541 (mandatory if fibre optic available)

Feeder KCEG142, MiCOM P127 Rectifier - primary MCAG33 or MiCOM P124 Rectifier - backup KCEG142 or MiCOM P127 Current check MCAG39 or MiCOM P122 System Transformer MiCOM P127

OC, EF, DOC, DEF

11kV Distribution Transformer (refer Section 6.6)

VIP35

Busbar MCAG34 Bus-zone Bus-tie cable MCAG34, P127 (when duplicate

protection required) Transformer differential SystemTransformer

(2 winding) KBCH120, MiCOM P632

Neutral leakage Transformer KCEG142 or MiCOM P127 MTA MVAJ11 (with flag) MTM MVAJ13 (hand reset with flag) Intertrip GCM05 (15kV isolation) TCS RMS 1TM10

48V DC supply RMS 1X10CAA Bus Supply 125V DC supply RMS 1X10EAA

Table 3 - Protection Relays

• The MBCI02 pilot wire relay is a specific model for use on the RailCorp system. The relay has been modified to produce a lower voltage suitable for the insulation level of communication pilots and is Austel approved.

Location of Protection Relays The physical location of protection relays will depend on the type of switchgear installed. In general the protection relays and associated test blocks for specific equipment shall be located together on the same panel.

This is usually on the low voltage compartment of the switchgear panels themselves (indoor switchgear) or on dedicated protection panels (for outdoor ACCB’s or indoor switchgear that does not have the physical space for installing the relays).



The particular requirements for specific relays and equipment are detailed below:

• Transformer protection - MTA and MTM relays located on the primary protection panel.

• 33/11kV transformer – neutral leakage relay shall be located on the 11kV switchgear panel.

• Bus-zone protection relay and associated MTM relay located on the appropriate end panel.

• Bus cable tie protection relay and associated MTM relay located on either of the associated bus tie ACCB panels.

• Pilot wire isolation transformers shall be located as close as possible to the termination enclosure of the pilot cable.



Appendix B ACCB Trip Coils - Standard Equipment Connection The following table details the ACCB trip coils and associated relays that are connected to each trip coil. This table is based on typical protection schemes used in RailCorp. Protection designs for specific locations must be verified by RailCorp. Refer to 6.1.1 for additional requirements relating to breaker fail schemes and Supply Points.

EQUIPMENT PROTECTION SCHEME TRIP COIL NUMBER

NOTES

Pilot wire 1 Overcurrent & Earth Fault 2

Feeder Protection

Inter-trip 1 Busbar protection – trips via MTM

2 1 Bus-zone & Bus-Tie

Cable Bus-tie protection – trips via MTM

1 4

Differential – trips via MTM or MTA

1

Overcurrent – trips via MTA 1,2 2

System Transformers

Neutral Leakage – trips via MTA

2

Differential – trips via MTM or MTA

1 11kV/415V Transformers

Overcurrent – trips via MTA 1,2 2, 5 Instantaneous Overcurrent 1 Rectifier

Transformers (primary prot’n) Earth Fault 1 via MTM

3

Instantaneous Overcurrent 2 Rectifier Transformers (backup prot’n) Earth Fault 2 & 1 via MTM

3

Rectifier Transformer

MTM 1

Table 4 - Trip Coils

Notes:

a) The operation of the bus-zone protection energises an MTM relay, which trips all ACCB’s on the section of the busbar. The trip coil number applies to all ACCB’s that are tripped.

b) If the differential protection operates via an MTM then the overcurrent protection shall trip via trip coil 2.

c) Refer to 6.4 for requirements of when earth faults are required to energise MTM.

d) When there is duplicate protection on the bus-tie cable the duplicate scheme shall trip the ACCB’s via trip coil 2 (via an MTM).

e) If there is no differential protection, then the overcurrent protection shall trip via trip coil 1.



Appendix C Two Battery Systems (125V DC) - Standard Protection Equipment Connection The following table details the battery system that the ACCB trip coils and protection relays should be connected to. This table is based on typical protection schemes used by RailCorp.

When there are two battery systems the equipment should be connected across the two battery systems to obtain balanced loads as close as possible.

Protection designs for specific locations must be verified by RailCorp. Refer to 5.5.2 for details of the requirement for two battery systems.

PRIMARY PROTECTION ONLY

PRIMARY & BACKUP PROTECTION LOCATED IN SAME SUBSTATION

ONE TRIP COIL

Protection relay supply from one battery Trip coil supply from same battery as relay supply

Primary protection relay supply from battery 1 Backup protection relay supply from battery 2 Trip coil supply from battery 1

TWO BATTERY SYSTEMS TWO

TRIP COILS

Protection relay supply from one battery Trip coil 1 supply from battery 1 Trip coil 2 supply from battery 2

Primary protection relay supply from battery 1 Backup protection relay supply from battery 2 Trip coil 1 supply from battery 1 Trip coil 2 supply from battery 2

Table 5 - Two Battery Systems – Connection of Equipment

Notes:

a) When there is only one battery system, the two trip coils must be supplied from separate submains originating from the 125V DC distribution board.

b) Refer to Appendix N for typical arrangement of auxiliary supplies to HV switchboards. This diagram illustrates the principle; however detailed design is required to ensure security of the protection scheme.



Appendix D Interfacing With Existing Pilot Wire Schemes The following table details whether the existing pilot wire scheme needs to be upgraded when a new switchboard is to be installed, and is interfacing with an existing pilot wire protection scheme.

SCHEME EXISTING EQUIPMENT

SCHEME TO BE REPLACED

NOTES

Pilot wire HO2 YES HO4 NO 2 HMB4 NO 1,2 MHOB04 NO 1 MBCI02 NO 1 MiCOM P521/P541 NO

Table 6 - Interfacing With Existing Pilot Wire Schemes

Notes:

a) If there are fibre optic pilots available between substations or fibre is to be installed, then pilot wire relays that use fibre optic for their communication (MiCOM P521/P541) shall be used.

b) If system spares are to be used to create/interface with an H04 or HMB4 scheme then the RailCorp Protection Engineer shall be consulted to ensure there are adequate spares available. If the number of spares available is at the minimum required number, then the pilot wire scheme shall be replaced.



Appendix E Current Transformers (33kV & 66kV) The following tables detail the ratio and designation of current transformers, which are to be used in the RailCorp electrical network for typical schemes on the 66kV & 33kV high voltage system.

The current transformer designation details are calculated based on the following parameters:

• Maximum CT secondary lead (loop) length of 20m with 2.5mm2 size cable for indoor equipment and a lead (loop) length of 150m with 16mm2 size cable for outdoor equipment.

• CT core knee point flux density of 1.45T • System X/R = 5 • MICOM P521 relay, refer to general equations for X/R<40 and tIdiff = 0.1s. • MBCI relay, refer to general equations, X=1, large X/R, Kt = 20. • Overcurrent and earth fault relays, Vk = In*If*(Rrelay+Rct+Rleads), with relay burdens

as specified by the manufacturer.

Where the equipment to be protected is not in the following tables or the standard parameters above are not applicable then the protection CT requirements must be determined on an individual basis.

Typical examples of these scenarios are:

• Lead lengths > 20m. • System transformers with a size or voltage not specified below. • Transformers with a different configuration. • Feeders with a higher capacity than 500A.

Rectifier Instantaneous Overcurrent & Earth Fault EQUIPMENT VOLTAGE/

SIZE CT RATIO RELAY TYPE CT DESIGNATION

MCAG33 10 P100F20 (specified on 200 tap) Rectifier Tx –

33kV 5.3, 4.28 & 2.5MVA

300/200/5 MiCOM P127 10 P50F20 (specified

on 200 tap) MCAG33 10 P100F20

(specified on 100 tap) Rectifier Tx – 66kV

5.3, 4.28, 2.5MVA

150/100/5 MiCOM P127 10 P50F20 (specified

on 100 tap)

Table 7 - Rectifier Protection Relays & CT’s

Overcurrent and Earth Fault CT’s for use on overcurrent and earth leakage on feeders have been sized on a fault level of 31.5kA at 33kV and 15.75kA at 66kV.

EQUIPMENT VOLTAGE/SIZE

SCHEME CT RATIO

RELAY TYPE CT DESIGNATION

KCEG142 10P150 66kV Feeder OC & EF 250/5 MiCOM P127 10P150



KCEG142 10P300 (specified on 300 tap) 33kV Feeder

OC & EF 500/400/300/5

MiCOM P127 10P300 (specified on 300 tap)

33/11KV Tx (5MVA )

33KV OC & EF 150/5 MiCOM P127 10P50F20

Table 8 - Overcurrent and Earth Fault Protection Relays & CT’s

Pilot Wire Schemes CT’s for use on pilot wire schemes have been sized on a fault level of 31.5kA at 33kV and 15.75kA at 66kV

EQUIPMENT CT RATIO RELAY TYPE CT DESIGNATION

250/5 MBCI02 or MiCOM P521/P541

0.3PL115R0.3

66kV Feeder

250/1 MBCI02 or MiCOM P521/P541

0.05PL50R0.8

500/400/300/5 MBCI02 or MiCOM P521/P541

0.3 PL200R0.3 (specified on 300 tap)

33kV Feeder

500/400/300/1 MBCI02 or MiCOM P521/P541

0.05 PL80R0.8 (specified on 300 tap)

Table 9 - Pilot Wire Protection Relays & CT’s

Bus-Zone Schemes & Transformer Differential The overall design of a bus-zone scheme is critical to ensure stability for through faults. The requirement for stabilising resistors to ensure stability and for metrosils to limit CT output voltage shall be determined for each individual scheme.

Please refer to the AREVA MCAG34 application brochure for methods of calculation and requirements.

CT’s for use on bus-zone schemes have been sized on a fault level of 31.5kA.

EQUIPMENT RELAY TYPE CT RATIO CT DESIGNATION 33kV Buszone MCAG34 1250/5 0.1 PL200R0.4

33/11kV Tx 5MVA, Dyn1 (differential)

KBCH120 (two winding), MiCOM P632

33kV - 150/5 2.5P50F20

Table 10 - Bus-Zone & Transformer Differential Protection Relays & CT’s

Notes:

a) The P632 relay should be ordered with an extra I/O module. This is required to allow for the transformer and tapchanger alarms.



Appendix F Current Transformers for 11kV Switchgear The following current transformer details are typical values only. The CT specification shall be determined for specific individual applications and is subject to RailCorp approval.

EQUIPMENT SCHEME CT RATIO RELAY TYPE

CT DESIGNATION

Notes

11kV Feeder Pilot Wire 300/1 MiCOM P521 0.05PL50R1.0

11kV Feeder OC & EF 300/150/1 MiCOM P127 10P50F20

Differential 450/0.577 MiCOM P632 0.02PL100R3.0 1

OC & EF 450/1 MiCOM P127 10P50F20 33/11kV Tx

(6.25 MVA ) Neutral leakage 150/1 MiCOM

P127 10P50F20

11KV/415V Tx (1MVA ) Differential 100/1 MiCOM

P632 0.15L50R0.3 1

Busbar Buszone 600/1 MCAG34 0.03PL120R2.0 2 Bus-tie Cables Buszone 600/1 MCAG34 0.03PL120R2.0 2

Notes:

a) The rated primary current value will depend on the size of the transformer.

b) The rated primary current value will depend on the rating of the busbar.



Appendix G Protection Relay Identification Device numbers and functions shall generally be in accordance with IEEE C.37.2. The detailed implementation shall be as set out below.

Relay Identifier Description 50A Instantaneous Overcurrent Relay (A phase) 50C Instantaneous Overcurrent Relay (C phase) 50/L Instantaneous Overcurrent Relay (A,C & E; feeder) 50/T Instantaneous Overcurrent Relay (A,C & E; transformer) 50/T1 Instantaneous Overcurrent Relay – Backup (A,C & E; transformer) 51A Inverse Time Overcurrent Relay (A phase) 51C Inverse Time Overcurrent Relay (C phase) 63 Buchholz Relay 64 Instantaneous Earth Fault Relay 67 Directional Overcurrent Relay 67/L Directional Overcurrent Relay (feeder) 87/B Differential Protective Relay (busbar – high impedance) 87/BT Differential Protective Relay (bus-tie cable – high impedance) 87/L Differential Protective Relay (feeder - pilot wire scheme) 87/T Differential Protective Relay (transformer) MTA Multi Trip Automatic Reset Relay MTM Multi Trip Manual Reset Relay SRR Send Receive Relay TBK1, 2 Test Block TCS Trip Circuit Supervisory Relay

Table 11 - Protection Relay Identification



Appendix H Standard Test Block Wiring & Input/Output Relay Configuration The following test block, protection relay input and output configurations are based on the majority of existing configurations in the RailCorp network. The configurations do not determine the requirement for a particular protection function, but detail the test block connections and output or input relay if that function is to be implemented.

It is not general practice to connect alarms via the test block or connect spare output relays to the test block. The test block shall be located adjacent to the protection relay it is associated with.

It is important that new installations comply with these diagrams as they affect the programming of electronic relays, the testing procedures for periodic maintenance and the production of standard designs.

Any deviations from the standard configuration must be approved by the Protection Engineer.

PILOT WIRE PROTECTION:

MBCI+MCRI Check Relays

Relay Incoming Supplies MMLG01

MBCI RELAY 1-1 contact 2 x 1 Trip +ve MBCI RELAY 1-1 contact 4 x 3 Pilot Wire Trip MCRI check contact 6 x 5 MBCI inhibit(11) MCRI check contact 8 x 7 Pilot 1 MBCI (17) 10 x 9 Pilot 1 Pilot 2 MBCI (18) 12 x 11 Pilot 2 MBCI&MCRI Aux 14 II 13 + 125V dc Aux MBCI&MCRI Aux 16 x 15 - 125V dc Aux 18 x 17 20 x 19 Ia (MBCI&MCRI) 22 x 21 Ia Ib (MBCI&MCRI) 24 x 23 Ib Ic (MBCI&MCRI) 26 x 25 Ic Io (MBCI&MCRI) 28 x 27 Io

MBCI RELAY OUTPUT RELAYS

RELAY 1-1 PILOT WIRE TRIP RELAY 1-2 PILOT WIRE TRIP ALARM RELAY 2-1 INTERTRIP SEND REALY 2-2 SPARE



MBOH04 RELAY


MBOH04 contact (1) 2 x 1 Trip +ve MBOH04 contact (2) 4 x 3 Pilot Wire Trip 6 x 5 Spare 8 x 7 Spare Pilot 1 MBOH04 10 x 9 Pilot 1 Pilot 2 MBOH04 12 x 11 Pilot 2 14 II 13 Spare 16 x 15 Spare 18 x 17 20 x 19 Ia (MBCI&MCRI) 22 x 21 Ia Ib (MBCI&MCRI) 24 x 23 Ib Ic (MBCI&MCRI) 26 x 25 Ic Io (MBCI&MCRI) 28 x 27 Io

P521 RELAY


RELAY 1 contact 2 x 1 Trip +ve RELAY 1 contact 4 x 3 Pilot Wire Trip 6 x 5 Spare 8 x 7 Spare 10 x 9 Spare 12 x 11 Spare TERMINAL 33 14 II 13 + 125V dc Aux Supply TERMINAL 34 16 x 15 - 125V dc Aux Supply RELAY 8 contact 18 x 17 Trip +ve RELAY 8 contact 20 x 19 Breaker FailTrip Ia 22 x 21 Ia Ib 24 x 23 Ib Ic 26 x 25 Ic Io 28 x 27 Io

OUTPUT RELAYS:

RELAY 1 PILOT WIRE TRIP RELAY 2 TCS ALARM RELAY 3 PILOT WIRE TRIP ALARM RELAY 4 COMMS FAIL ALARM RELAY 5 SPARE RELAY 6 BREAKER FAIL ALARM RELAY 7 SPARE RELAY 8 BREAKER FAIL TRIP



INPUT RELAYS:

L1 INTERIPT INITIATE L2 TCS INPUT L3 SPARE L4 SPARE L5 SPARE

SIEMENS 7SD610 RELAY


RELAY BO4 contact 2 x 1 Trip +ve RELAY BO4 contact 4 x 3 Pilot Wire Trip 6 x 5 Spare 8 x 7 Spare RELAY BO5 contact 10 x 9 Trip +ve RELAY BO5 contact 12 x 11 Intertrip Trip TERMINAL F1 14 II 13 + 125V dc Aux Supply TERMINAL F2 16 x 15 - 125V dc Aux Supply RELAY BO3 contact 18 x 17 Trip +ve RELAY BO3 contact 20 x 19 Breaker FailTrip Ia 22 x 21 Ia Ib 24 x 23 Ib Ic 26 x 25 Ic Io 28 x 27 Io

OUTPUT RELAYS:

BO1 EA ACCB STATUS BO2 COMMS FAIL ALARM BO3 BREAKER FAIL ALARM BO4 PILOT WIRE TRIP BO5 INTERTRIP RECEIVE

Note: Output replays BO1, BO2 and BO3 are not voltage free contacts. The +125V DC for the breaker fail trip is also connected to B01& B02 contacts by internal relay wiring.

RECTIFIER OC & EF PROTECTION

P127 RELAY


RELAY 1 contact 2 x 1 Trip +ve RELAY 1 contact 4 x 3 Overcurrent Trip RELAY 3 contact 6 x 5 Trip +ve RELAY 3 contact 8 x 7 Earth Fault Trip 10 x 9 Spare 12 x 11 Spare TERMINAL 33 14 II 13 + 125V dc Aux Supply TERMINAL 34 16 x 15 - 125V dc Aux Supply



RELAY 8 contact 18 x 17 Trip +ve RELAY 8 contact 20 x 19 Breaker FailTrip Ia 22 x 21 Ia Ib 24 x 23 Ib Ic 26 x 25 Ic Io 28 x 27 Io

OUTPUT RELAYS: RELAY 1 OVERCURRENT & EARTH FAULT TRIP RELAY 2 TCS ALARM RELAY 3 EARTH FAULT TRIP RELAY 4 OVERCURRENT ALARM RELAY 5 EARTH FAULT ALARM RELAY 6 BREAKER FAIL ALARM RELAY 7 SPARE RELAY 8 BREAKER FAIL TRIP INPUT RELAYS: INPUT L1 SPARE INPUT L2 SPARE INPUT L3 SPARE INPUT L4 TCS INPUT L5 TIMER INITIATE INPUT L6 SPARE INPUT L7 SPARE

RECTIFIER OC & EF PROTECTION


MCAG trip contact 2 x 1 MVAJ13 Trip +ve MCAG trip contact 4 x 3 MVAJ13 Trip Spare trip contact 6 x 5 Spare trip contact Spare trip contact 8 x 7 Spare trip contact Spare 10 x 9 Spare Spare 12 x 11 Spare Spare 14 II 13 Spare Spare 16 x 15 Spare Spare 18 x 17 Spare Spare 20 x 19 Spare Ia 22 x 21 Ia Ib 24 x 23 Ib Ic 26 x 25 Ic Io 28 x 27 Io

RELAY CONTACTS: A∅ contacts: terminals 1 & 3 : trip

2 & 4 SCADA alarm

E/F contacts: terminals 5 & 7 : trip 6 & 8 SCADA alarm



C∅ contacts: terminals 9 & 11 : trip 10 & 12 SCADA alarm

Notes:

1. A & C phase trip contacts are connected in parallel at the relay terminals.



33/11kV TRANSFORMER OC & EF PROTECTON

P127 RELAY


RELAY 7 contact 2 x 1 Trip +ve RELAY 7 contact 4 x 3 Overcurrent Trip RELAY 3 contact 6 x 5 Trip +ve RELAY 3 contact 8 x 7 Earth Fault Trip 10 x 9 Spare 12 x 11 Spare TERMINAL 33 14 II 13 + 125V dc Aux Supply TERMINAL 34 16 x 15 + 125V dc Aux Supply RELAY 8 contact 18 x 17 Trip +ve RELAY 8 contact 20 x 19 Breaker Fail Trip Ia 22 x 21 Ia Ib 24 x 23 Ib Ic 26 x 25 Ic Io 28 x 27 Io

OUTPUT RELAYS:

RELAY 1 NOT AVAILABLE * RELAY 2 TCS ALARM RELAY 3 EARTH FAULT TRIP RELAY 4 OVERCURRENT ALARM RELAY 5 EARTH FAULT ALARM RELAY 6 BREAKER FAIL ALARM RELAY 7 OVERCURRENT TRIP RELAY 8 BREAKER FAIL TRIP

INPUT RELAYS:

INPUT L1 SPARE INPUT L2 SPARE INPUT L3 SPARE INPUT L4 TCS INPUT L5 SPARE INPUT L6 SPARE INPUT L7 SPARE

* THE BREAKER FAIL FUNCTION OF THE RELAY IS INITIATED INTERNALLY BY RELAY 1. HENCE RELAY 1 IS PROGRAMMED TO BE ENERGISED FOR EITHER AN OVERCURRENT OR EARTH FAULT TRIP. HOWEVER, IT IS NOT CONNECTED EXTERNALLY AS AN OVERCURRENT TRIP IS REQUIRED TO ENERGISE AN MTA RELAY AND THE EARTH FAULT TRIP IS REQUIRED TO ENERGISE AN MTM RELAY.



11kV DISTRIBUTION TRANSFORMER OC & EF PROTECTION

VIP300LL RELAY


TERMINAL 15 2 x 1 Trip -ve TERMINAL 16 4 x 3 Trip +ve 6 x 5 Spare 8 x 7 Spare 10 x 9 Spare 12 x 11 Spare 14 II 13 Spare 16 x 15 Spare TERMINAL 12 18 x 17 Ia TERMINAL 8 20 x 19 Ia TERMINAL 11 22 x 21 Ib TERMINAL 6 24 x 23 Ib TERMINAL 10 26 x 25 Ic TERMINAL 4 28 x 27 Ic

11kV DISTRIBUTION TRANSFORMER OC & EF PROTECTION

VIP300LL RELAY

Relay (x4 range 50-200A) Incoming Supplies MMLG01

TERMINAL 15 2 x 1 Trip -ve TERMINAL 16 4 x 3 Trip +ve 6 x 5 Spare 8 x 7 Spare 10 x 9 Spare 12 x 11 Spare 14 II 13 Spare 16 x 15 Spare TERMINAL 12 18 x 17 Ia TERMINAL 7 20 x 19 Ia TERMINAL 11 22 x 21 Ib TERMINAL 5 24 x 23 Ib TERMINAL 10 26 x 25 Ic TERMINAL 3 28 x 27 Lc



FEEDER DOC & DEF PROTECTION

P127 RELAY


RELAY 1 contact 2 x 1 Trip +ve RELAY 1 contact 4 x 3 Trip Va 6 x 5 Va Vb 8 x 7 Vb Vc 10 x 9 Vc Vn 12 x 11 Vn TERMINAL 33 14 II 13 + 125V dc Aux Supply TERMINAL 34 16 x 15 - 125V dc Aux Supply RELAY 8 contact 18 x 17 Trip +ve RELAY 8 contact 20 x 19 Breaker Fail Trip Ia 22 x 21 Ia Ib 24 x 23 Ib Ic 26 x 25 Ic Io 28 x 27 Io

OUTPUT RELAYS:

RELAY 1 OVERCURRENT & EARTH FAULT TRIP RELAY 2 TCS ALARM RELAY 3 SPARE RELAY 4 OVERCURRENT ALARM RELAY 5 EARTH FAULT ALARM RELAY 6 BREAKER FAIL ALARM RELAY 7 INTERTRIP SEND (IF REQUIRED) RELAY 8 BREAKER FAIL TRIP

INPUT RELAYS:

INPUT L1 SPARE INPUT L2 SPARE INPUT L3 SPARE INPUT L4 TCS INPUT L5 SPARE INPUT L6 SPARE INPUT L7 SPARE



FEEDER DOC & DEF PROTECTION

KCEG142 RELAY


KCEG142 trip contact 2 x 1 52 Trip +ve KCEG142 trip contact 4 x 3 52 Trip Va 6 x 5 Va Vb 8 x 7 Vb Vc 10 x 9 Vc Vn 12 x 11 Vn KCEG142 Aux 14 II 13 + 125V dc Aux KCEG142 Aux 16 x 15 - 125V dc Aux KCEG142 ACCB fail trip contact

18 x 17 ACCB/fail trip +ve

KCEG142 ACCB fail trip contact

20 x 19 ACCB/fail multitrip

Ia 22 x 21 Ia Ib 24 x 23 Ib Ic 26 x 25 Ic Io 28 x 27 Io

OUTPUT RELAYS:

RELAY 0 SPARE RELAY 1 BREAKER FAIL ALARM RELAY 2 SPARE RELAY 3 OVERCURRENT & EARTH FAULT TRIP RELAY 4 OVERCURRENT ALARM RELAY 5 EARTH FAULT ALARM RELAY 6 SPARE RELAY 7 BREAKER FAIL TRIP



TRANSFORMER DIFFERENTIAL PROTECTION

P632/MBCH RELAY


P632/MBCH trip contact 2 x 1 MVAJ Trip +ve P632/MBCH trip contact 4 x 3 MVAJ Trip Spare 6 x 5 Spare Ia’’ (delta connected C.T’s) 8 x 7 Ia Ib’’ (delta connected C.T’s) 10 x 9 Ib Ic’’ (delta connected C.T’s) 12 x 11 Ic P632/MBCH Aux 14 II 13 + 125V dc Aux P632/MBCH Aux 16 x 15 - 125V dc Aux Spare 18 x 17 Spare Spare 20 x 19 Spare Ia 22 x 21 Ia Ib 24 x 23 Ib Ic 26 x 25 Ic Io 28 x 27 Io

OUTPUT RELAYS (P632):

K901 TX DIFFERENTIAL TRIP K701 TAP CHANGER PRESSURE SWITCH ALARM

K902 RELAY HEALTHY K702 BREAKER FAIL ALARM K903 BREAKER FAIL TRIP K703 TAP CHANGER OIL SURGE

ALARM K904 TX DIFFERENTIAL TRIP ALARM K704 SPARE K905 TX BUCHHOLZ GAS ALARM K705 SPARE K906 TX BUCHHOLZ OIL ALARM K706 SPARE K907 TAP CHANGER ALARM K707 SPARE K908 TCS ALARM K708 SPARE

INPUT RELAYS (P632):

U901 TAP CHANGER OIL SURGE OPERATION U902 TX BUCHHOLZ OIL SURGE OPERATION U903 TX BUCHHOLZ GAS OPERATION U904 TAP CHANGER ALARM U701 TAPCHANGER PRESSURE SWITCH U702 TCS U703 SPARE U704 SPARE U705 SPARE U706 SPARE



DIRECTIONAL OC/E FEEDER PROTECTION:

RELAY: MCGG52 + METI


MCGG trip contact 2 x 1 52 Trip +ve MCGG trip contact 4 x 3 52 Trip Va 6 x 5 Va Vb 8 x 7 Vb Vc 10 x 9 Vc METI Aux 12 x 11 MCGG &METI Aux 14 II 13 + 125 V dc Aux MCGG Aux 16 x 15 - 125 V dc Aux Vo1 (open delta voltage) 18 x 17 Vo1 Vo2 (open delta voltage) 20 x 19 Vo2 Ia 22 x 21 Ia Ib 24 x 23 Ib Ic 26 x 25 Ic Io 28 x 27 Io



FEEDER PROTECTION, OVERCURRENT & EARTH FAULT

RELAY: MCGG52/82


MCGG trip contact 2 x 1 52 Trip +ve MCGG trip contact 4 x 3 52 Trip Spare 6 x 5 Spare Spare 8 x 7 Spare Spare 10 x 9 Spare Spare 12 x 11 Spare MCGG Aux 14 II 13 + 125 V dc Aux MCGG Aux 16 x 15 - 125 V dc Aux Spare 18 x 17 Spare Spare 20 x 19 Spare Ia 22 x 21 Ia Ib 24 x 23 Ib Ic 26 x 25 Ic Io 28 x 27 Io

BUS – TIE / BUS ZONE PROTECTION

MCAG34 RELAY


MCAG trip contact 2 x 1 Trip +ve MCAG trip contact 4 x 3 Trip Spare trip contact 6 x 5 Spare trip contact Spare trip contact 8 x 7 Spare trip contact Spare 10 x 9 Spare Spare 12 x 11 Spare Spare 14 II 13 Spare Spare 16 x 15 Spare Spare 18 x 17 Spare Spare 20 x 19 Spare Ia 22 x 21 Ia Ib 24 x 23 Ib Ic 26 x 25 Ic Io 28 x 27 Io



RELAY CONTACTS:

A∅ contacts: terminals 1 & 3 : trip 2 & 4 SCADA alarm

B∅ contacts: terminals 5 & 7 : trip 6 & 8 SCADA alarm

C∅ contacts: terminals 9 & 11 : trip 10 & 12 SCADA alarm

Notes:

1. A, B &, C phase trip contacts are connected in parallel at the relay terminals.

RECTIFIER LOCAL BACKUP PROTECTION

MVTT14 + MCTI39 RELAYS


MCTI trip contact 2 x 1 52 Trip +ve MCTI trip contact 4 x 3 52 Trip MCTI current check 6 x 5 CB/fail trip +ve MCTI current check 8 x 7 lLocal bu +ve 10 x 9 CAG33 contact MVTT start 12 x 11 CAG33 contact Local bu +ve 14 II 13 + 125V dc local bu Aux Local bu -ve 16 x 15 - 125V dc local bu Aux MVTT Breaker fail trip contact

18 x 17

MVTT Breaker fail trip contact

20 x 19 CB/fail multitrip

MCTI Ia 22 x 21 Ia MCTI Ib 24 x 23 Ib MCTI Ic 26 x 25 Ic MCTI Io 28 x 27 Io



Appendix I Voltage and Current Transducers Transducers that are to be used to provide the SCADA system with current and voltage information relating to the high voltage network shall have the following general characteristics:

• Output of 0…20mA • Mean sensing • Self powered

The following transducer is approved for connection in the protection current transformer circuit.

• Areva Istat 300; Type 3CAEA513AA (for CT’s with 1A secondaries) • Areva Istat 300; Type 3CAEA55GKA (for CT’s with 5A secondaries)

The following transducer is approved for connection in the voltage transformer circuit.

• Areva Istat 300; Type 3VAEA5450A, (nominal input range of 0-125V ac to measure a 110V ac voltage transformer output, usually measuring the voltage between A∅ & C∅).


Appendix J Pilot Wire Schemes




Appendix K Auto Re-close on High Voltage Feeders The RailCorp re-closure policy is as follows:

In general, one auto re-close in 5 seconds by SCADA (ie the master station initiates the auto re-close if all the requirements are met).

This policy applies to the following:

• 2kV, 11kV, 33kV 66kV aerial lines • 11kV, 33kV 66kV cables, no auto re-close • 2kV signalling cables do have auto re-close because of the criticality of maintaining

the supply and often the fault blows clear. • A feeder that is partially cable and partially aerial line is treated as aerial line.

The auto re-close is taken off 33kV and 66kV feeders that traverse areas considered to be a bush fire risk when fire bans are imposed. This is a master station function initiated by the ESO's.

Auto re-close is also automatically inhibited for 10 minutes after a close control.



Appendix L Protection SCADA Alarms PROTECTION SCADA ALARMS

ORIGIN OF ALARM SCADA ALARM NAME COMMENTS ACCB SpringCharged LowGas LowGasLockOut

The number of alarm stages will depend on the ACCB being installed.

MotorSupply MotorTrouble PROTECTION RELAY DirectionProtectionA DirectionProtectionB DirectionProtectionC DirectionRelayFail DirectionalDCSupply PilotWireTripA PilotWireTripB PilotWireTripC BrokenConductorA BrokenConductorB BrokenConductorC PilotWireComms PilotWireRelayFail OverCurrentA OverCurrentB OverCurrentC EarthLeakage InstOverCurrentA InstOverCurrentB InstOverCurrentC Inst_OC/ELtrip OverCurrentRelayFail BreakerFail NeutralLeakageProtection IntertripReceive IntertripSend BusZone1 BusZone2 BusZone3 BusZoneRelayFail DifferentialProtectionA DifferentialProtectionB DifferentialProtectionC DifferentialRelayFail TripCircuitSupervision



PROTECTION SCADA ALARMS ORIGIN OF ALARM SCADA ALARM NAME COMMENTS TRANSFORMER BuchholzGas BuchholzOil TCBuchholzGas TCBuchholzOil TCFail TCLowLimit TCHighLimit TCControlSupply TCInProgress TCIncomplete TCRefSupplyAlarm

These alarms originate from the transformer tap changer.

TemperatureAlarm This alarm originates from the temperature indicators on the transformer. There could possibly be several stages.

VOLTAGE TRANSFORMER

PhaseFailure This alarm originates from a dedicated phase failure relay connected to the output of the VT.

DirectionalAlarm This alarm originates from a LV circuit breaker that supplies the voltage to the specific directional protection relay.

DCCB Frame Leakage DCFrameLeakage BATTERY CHARGER BattChargerAC BattUnderVolts BattOverVolts BattConnected

These alarms originate from the battery charger and the exact alarms available will depend on the battery charger.

Not all the alarms in the above list will be applicable. When determining the proposed alarms the following factors must be considered:

• Type of relay • Capacity of RTU • Function of relay • Value adding of the alarm information to the EOC operator and RailCorp Protection

Engineer.

In many existing locations some of the protection alarms (eg. TCS) are connected in parallel for each piece of equipment to give one general alarm. This was due to the limitations on the quantity of alarms that could be connected to the RTU at the time of installation.



Appendix M Implementation Of SCADA Alarms & Control The SCADA alarms and control to and from equipment can be implemented by hard wiring or using a high level interface such as a serial link.

Electronic protection relays can be used to convey the information by using discrete output relays or via serial links. However certain information is critical for system operation and must be independent on the protection relay or communication link to the RTU.

The following list details the SCADA alarms and control that are required to be hard wired to the RTU.

• ACCB control • ACCB indication (both open and closed) • ACCB DISCONNECTOR/ISOLATOR indication (all positions)* • EARTH SWITCH indication (both open and closed)* • Tapchanger control • Battery Charger alarm • Protection relay watchdog alarms • Trip Circuit Supervision (TCS), where provided by a dedicated TCS relay. • Analogues (current and voltage) • Phase failure relay • * If all circuit breakers on a switchboard are not fitted with electronic relays having

adequate RS485 communications to the RTU


Appendix N Typical ACCB Auxiliary Supply Arrangement






Appendix O Protection Relay Labelling Guidelines The following rules apply to the labelling of protection relays and associated auxiliary relays:

• Location of Labels:

– Labels should be located above the relay. If this is not possible, then they should be located directly below the relay.

• Colour of Labels:

– All protection relays labels shall have black writing on a yellow background. – All auxiliary relays (such as multi-trip relays) shall have black writing on a white

background.

• Format

– To keep the length of labels to a minimum, abbreviations shall be used for the protection functions. The valid abbreviations are detailed in Table N1.

– All labels are to be in CAPITALS (except for abbreviations such as “Tx” & “kV”). – The description of equipment shall be consistent with terminology as used in the

AC operating diagrams. This is summarised below: – FEEDERS: “Feeder ID” ; – Where “Feeder ID” is the unique 3 digit identification assigned to each high

voltage feeder. – TRANSFORMERS: “Unit ID” + “voltage ratio” + “Tx” ; – Where “Unit ID” is the identification given where there are multiple transformers

(eg. No.1, No.2 etc). “voltage ratio” is the voltage ratio of the transformer usually expressed in kV (eg. 33/11kV, 66/33kV).

– RECTIFERS: “Unit ID” + “RECTIFIER” – Where “Unit ID” is the identification given where there are multiple rectifiers (eg.

No.1, No.2 etc).

• Content:

FIRST LINE OF LABEL:

The following sequence should be used to construct a label:

i) Equipment being Protected/Monitored

eg. No.1 RECTIFIER BUS ZONE 792 No.2 33/11kV Tx

ii) Type of Protection

eg. DOC & DE RELAY PW RELAY A∅ DOC RELAY A∅ OC RELAY FL RELAY Tx OC RELAY Tx DIFF RELAY



iii) Make of Relay in Brackets.

eg. (HMB4), (P521), (HO4) (CDD31), (P127), (CRP7), (CR LE) (P632), (KBCH), (DDT)

iv) Pointer to Relay (if needed)

eg. ↑ ↓

EXAMPLES OF LABELS:

798 DOC & DE RELAY (P127) 798 PW RELAY (P521) ↑ No.1 RECT IOC & IE RELAY (MCAG33) No.1 RECT IOC & IE BACKUP RELAY (P127) TRIP CCT 1 TCS RELAY (1TM10) No.1 33/11kV TxDIFF RELAY (P632) No.1 33/11kV Tx OC & E RELAY (P127) 1-2 BZT RELAY (MCAG34) ↓ 1-2 BZT MTM RELAY (MVAJ13) No.1 33/11kV Tx MTA RELAY (MVAJ11) No.1 SECTION BZ MTM RELAY (MVAJ13)

PROTECTION FUNCTION ABBREVIATION ARC DETECTION AD BUCHHOLZ B BREAKER FAIL BF BLOCKING RELAY BRly BACKUP BU BUS ZONE BZ BUS ZONE TIE BZT DIRECTIONAL EARTH FAULT DE DIRECTIONAL INSTANTANEOUS OVERCURRENT DIOC DIRECTIONAL OVERCURRENT DOC EARTH FAULT E DCCB FRAME LEAKAGE FLDC AC FRAME LEAKAGE FL RECTIFIER FRAME LEAKAGE FLR INSTANTANEOUS EARTH LEAKAGE IE INTELLIGENT GAS INFORMATION SYSTEM IGIS INTELLIGENT LIGHT INFORMATION SYSTEM ILIS INSTANTANEOUS OVERCURRENT IOC INTERTRIP IT INSTANTANEOUS & TIME DELAY OVERCURRENT ITOC MUTI TRIP RELAY – AUTOMATIC RESET MTA MULTI TRIP RELAY – MANUAL RESET (HAND) MTM NEUTRAL LEAKAGE NL OVERCURRENT OC LOW OIL LO OVERCURRENT & RESIDUAL EARTH FAULT INVERSE TIME ORET PRESSURE SWITCH PS PILOT WIRE PW DC REVERSE CURRENT RC TRANSFORMER DIFFERENTIAL TxDIFF TRANSFORMER WINDING TEMPERATURE WT TRIP CIRCUIT SUPERVISION TCS



PROTECTION FUNCTION ABBREVIATION TRIP SUPPLY SUPERVISION TSS

Table 12 - Protection Function Abbreviations


Appendix P Standard Current Transformer Configurations








Appendix Q Protection Non-Compliances Particular to the ECRL Project This appendix details known design issues relating to the protection schemes and equipment installed in the ECRL project that do not comply with the general requirements of this standard.

These arrangements have been accepted for the ECRL project only.

11kV Protection • Bus-zone protection not installed on the 11kV switchboards, (blocking scheme

installed in lieu). • Pilot wire protection not installed on the 11kV feeders. • Multi-trip relays not used. • Dual trip coils not installed. • Test blocks not wired in accordance with standard configuration. • Protection relays not programmed with standard configuration.

33kV Protection • Multi-trip relays not used on the 33/11kV transformer protection (pushbutton

installed to reset latched P632 output relays). • Dual trip coils not installed. • Test blocks not wired in accordance with standard configuration. • Protection relays not programmed with standard configuration.