High Voltage Cable Routes

Transcription

1 Engineering Specification Electrical L1-CHE-SPE-070 High Voltage Cable Routes Version: 2 Issued: October 2017 Owner: Chief Engineer Approved By: Andrew Russack Head of Electrical Engineering PRINTOUT MAY NOT BE UP-TO-DATE; REFER TO METRO INTRANET FOR THE LATEST VERSION

2 Approval Amendment Record Approval Date Version Description 11/05/ Initial issue 25/10/ Minor corrections and clarifications throughout. Requirement for fault loop lengths and installation revised. Usage of sand pits revised and clarified. PRINTOUT MAY NOT BE UP-TO-DATE; REFER TO METRO INTRANET FOR THE LATEST VERSION Page 2 of 30

3 Table of Contents 1 Purpose Scope Abbreviation Definitions References & Legislations MTM Standards/Documents Rail Industry Standards/Documents Australian Standards/Documents Related Documents General Compliance Permitted Configurations Cable Route Alignment Under Track Crossings Cable Joints Cable Fault Loops Ground Entry Arrangements Separation of Services Underground Conduits Structure Mounted Conduits Ground Level Troughing Metallic Trunking Cable Pits and Chambers Pit and Chamber Types Pit and Chamber Locations Formed Pit and Chamber Requirements General Pit or Chamber Size Pit or Chamber Installation Cable Entry Cable Support Protection Pit Access Sand Pit Requirements Location Requirements Construction Protection and Marking PRINTOUT MAY NOT BE UP-TO-DATE; REFER TO METRO INTRANET FOR THE LATEST VERSION Page 3 of 30

4 10 Conduit Conduit Requirements Conduit Installation Underground Installation Installation by Excavation Bored Installation Protection Structure Mounted Installation Acceptable Usage Cases Installation Requirements Protection and Labelling Strength Spares Direct Buried Cable Ground Level Troughing and Trunking Acceptable Usage Cases Ground Level Troughing Trunking Marking, Labelling and Record Keeping Recording of Cable Routes and Cable Plans Cable Route Markers Cable Labelling Pit Marking Construction Qualification General Fill and Compaction Installation in Tunnels Inspection and Testing Conduit Testing PRINTOUT MAY NOT BE UP-TO-DATE; REFER TO METRO INTRANET FOR THE LATEST VERSION Page 4 of 30

5 Table of Figures Figure 1: Typical Fault Loop Installations for Joints Sand Pit Figure 2: Typical Fault Loop Installation for Joint Formed Pit Figure 3: Typical Fault Loop Installation for Joint Formed Pit Figure 4: Typical Fault Loop Installation Sand Pit for Ground Entry from a Structure Figure 5: Typical mechanical protection on 1500V mast Figure 6: Separation Distance Figure 7: Cable Joint Supported in Pit Figure 8: Sand Pit Construction Figure 9: Typical Pit Entry Conduit sloping away from pit Figure 10: Buried Conduit Installation Figure 11: Conduit Protection by Other Services Figure 12: Mandrel for Conduit Testing PRINTOUT MAY NOT BE UP-TO-DATE; REFER TO METRO INTRANET FOR THE LATEST VERSION Page 5 of 30

6 1 Purpose This specification sets out requirements for conduits, pits, troughing, trunking and the configuration of cable routes for MTM High Voltage cables, including but not limited to traction cables, feeder cables, electrolysis cables and signal or essential services power distribution cables. 2 Scope This standard is to be complied with for all installations of MTM High Voltage cables. This standard does not cover aerial lines associated with the above systems, or installations within buildings, switchyards or equipment cases. This specification supersedes VRIOGS for the purposes of MTM High Voltage cables except as referred to within this document. Any clarification required shall be sought from the Head of Engineering Electrical. 3 Abbreviation AC Alternating Current DC Direct Current HV High Voltage LV Low Voltage MTM Metro Trains Melbourne O/H Overhead PTV Public Transport Victoria S/S Substation 4 Definitions Chamber Clean sand Constructor Formed pit A formed pit of sufficient size to enable a person to stand and work within it. Clean washed river sand free of rocks, clay lumps, tree roots, building rubble, metal, glass, sharp objects, organic solvents or other deleterious material that is likely to damage cables. A person or group of people tasked with the control of the work site that contains the underground cable. A formed chamber or cable pit installed beneath the ground for the purpose of containing cable joints, fault loops or bends. PRINTOUT MAY NOT BE UP-TO-DATE; REFER TO METRO INTRANET FOR THE LATEST VERSION Page 6 of 30

7 High Voltage For the purpose of this standard the term High Voltage includes equipment and other electrical apparatus associated with the following systems: Low Voltage Pit Sand pit Shall Should Specification Structure Mounted Conduit Trunking Underground Services 1500V DC Traction (including Traction Negative) Electrolysis 6.6kV, 11kV and 22kV feeders 650V, 1000V, 2200V, 3300V and 6600V signal or essential services power distribution It also includes any other equipment operating at nominal voltages of 650V or above. Any voltage less than or equal to 650V, excluding those systems specifically defined as High Voltage in this standard. A formed pit or sand pit An excavation for the purpose of containing cable joints, fault loops, or bends, where the excavation is backfilled to the surface with sand supporting the cables and access reserved for future maintenance. Is used as the descriptive word to express a requirement that is mandatory to achieve conformance to the standard. Is used as the descriptive word to express a requirement that is recommended in order to achieve compliance to the standard. Should can also be used if a requirement is a design goal but not a mandatory requirement. A set of requirements that are mandatory to be adhered to achieve MTM s objectives. Conduit mounted in accordance with the requirements of section Galvanised Steel Troughing, installed as described in section 8.0 of VRIOGS Rev A Cables, conduits, pipes or similar that are underground and used for utilities such as water, power, gas, drainage or communications. PRINTOUT MAY NOT BE UP-TO-DATE; REFER TO METRO INTRANET FOR THE LATEST VERSION Page 7 of 30

8 5 References & Legislations All references to standards or other documents shall be taken to be a reference to the latest version of that document inclusive of any amendments at the time of reading. 5.1 MTM Standards/Documents Document Number IPG OR-01 L4-CHE-STD-009 L4-CHE-STD-011 L1-SDD-STD-006 L1-CHE-STD-010 L1-CHE-STD-016 L1-CHE-GDL-029 L1-INF-PRO-001 Electrical Safety Rules Title Traction Substations and Tie Stations Overhead Line Electrification Train Maintenance Buildings Electrical Systems Earthing And Bonding Railway Bridges Electrical Protection and Bonding Track Bonding For Signalling and Traction Return Current Chief Engineer s Directive - Conduit Usage in Sunlight Protection of Underground Assets and Services Procedure 5.2 Rail Industry Standards/Documents Document Number N/A VRIOGS VRIOGS Title PTV Infrastructure Drawing Standards Specification for Signalling Supply, Construction and Installation Standard for Construction of Cable Route and Signalling Civil Works 5.3 Australian Standards/Documents Document Number AS 1319 AS 1477 AS 1657 AS AS 2053 AS AS 2865 AS 3000 AS 3008 Title Safety signs for the occupational environment PVC pipes and fittings for pressure applications Fixed platforms, walkways, stairways and ladders Design, construction and installation Industrial fall-arrest systems and devices - Selection, use and maintenance Conduits and fittings for electrical installations Underground marking tape - Non-detectable tape Safe working in a confined space Electrical installations (known as the Australian / New Zealand Wiring Rules) Electrical installations Selection of cables PRINTOUT MAY NOT BE UP-TO-DATE; REFER TO METRO INTRANET FOR THE LATEST VERSION Page 8 of 30

9 Document Number Title AS 3600 AS 3572 AS 3798 AS 3996 AS 4130 AS 4702 AS 4799 AS/CA S009 ESAA C(b)2 SAA HB 29 Concrete structures Plastics - Glass filament reinforced plastics (GRP) - Methods of test Guidelines on earthworks for commercial and residential developments Metal access covers, road grates and frames Polyethylene (PE) pipes for pressure applications Polymeric cable protection covers Installation of underground utility services and pipelines within railway boundaries Installation requirements for customer cabling (Wiring Rules) Guide to the Installation of Underground Cables Communications cabling handbook N/A Victorian Service and Installation Rules 2014 N/A Electricity Safety (Installation) Regulations Related Documents Document Number L1-INF-PRO-001 L2-TRK-PRO-032 TS-SP015 Title Protection of Underground Assets and Services Procedure Track Procedure Maintaining Track Integrity VicTrack Network Protection Plan 7 General 7.1 Compliance High Voltage Cable Routes shall comply with this document, AS 3000, the Electricity Safety (Installations) Regulations 2009 and all other standards detailed in this specification. Where a conflict exists between those documents and this specification, clarification shall be sought from the Head of Engineering Electrical. 7.2 Permitted Configurations Cables should be installed in buried conduit. Cables shall not be run in a route listed as not permitted in Table 1. The use of ground level troughing or metallic trunking for HV cables shall require a safety and reliability/maintainability case to be presented for endorsement by the Head of Engineering Electrical. It shall be demonstrated that underground conduit installation is impracticable and/or that the works are intended to be temporary. PRINTOUT MAY NOT BE UP-TO-DATE; REFER TO METRO INTRANET FOR THE LATEST VERSION Page 9 of 30

10 Table 1: Permitted Configurations Buried Conduit Structure Mounted Conduit Ground Level Troughing Metallic Trunking Signal or Essential Services Power Distribution (650V-6.6kV AC) Preferred Acceptable With Endorsement With Endorsement 6.6kV/11kV/22kV AC Preferred Acceptable Not Permitted Not Permitted 1500V DC Preferred Acceptable Not Permitted Not Permitted Traction Negative Preferred Acceptable Not Permitted Not Permitted Electrolysis Preferred Acceptable Not Permitted Not Permitted 7.3 Cable Route Alignment Cables shall be run in straight lines as far as is practicable within the rail easement. Cables may be run outside of the rail easement in accordance with an approved design acceptable to the Head of Engineering Electrical, as permitted by S.46 of the Electricity Safety Act Where cables are required to run parallel to the rail line the route should be aligned as far as practicable from the rail lines and as a minimum the following clearances shall be maintained: Table 2: Minimum Clearances for Route Alignment From Outside Rail From Structure Foundations Underground Conduit (except ground entry arrangements, under track crossings) 4000mm 2000mm Structure Mounted Conduit In accordance with VRIOGS 001 Ground Level Troughing 3000mm 2000mm Metallic Trunking In accordance with VRIOGS m from outside rail wherever practicable Ground Entry Arrangements 3000mm, or in line with structure No requirement Cable routes shall be approved by both the Head of Engineering Electrical and the Head of Engineering Track and Structures or their nominees. Signal and Essential Services cable routes shall also be approved by the Head of Engineering Signals or their nominee. PRINTOUT MAY NOT BE UP-TO-DATE; REFER TO METRO INTRANET FOR THE LATEST VERSION Page 10 of 30

11 7.4 Under Track Crossings Where cables are required to cross below rail tracks, they shall be run orthogonally to the tracks. Cables crossing beneath rail tracks shall be installed in conduit either by boring or trenching. The minimum depth when passing below rail tracks shall be 1200mm from the top of rail to the top of an HV conduit, which shall be maintained for at least 3000mm beyond the outside rails, or to an attached ground entry arrangement. This requirement is in addition to the depth requirements specified in section 10.3 which shall be maintained throughout the rail reserve including beneath cess drains. 7.5 Cable Joints All cable joints shall be installed within pits refer to section 9. No cable joints shall be present in new cable installations where the length of the cable to be installed is less than the length of cable on a new cable drum. Unnecessary joints in new cables are not permitted. 7.6 Cable Fault Loops Fault loops shall be provided for cables with a length greater than 100m. The additional cable length to be provided in the loop shall be suitable for two replacements of a joint or termination. The minimum acceptable lengths of fault loops are shown in Table 3 below. They shall be provided at each termination, and on both sides of a joint. Service Table 3: Fault Loop Lengths Typical termination/joint length Minimum acceptable fault loop length (each side of joints) 22kV 1.2m 2.5m 1500V (pos. or neg.) 500mm 1.2m 3.3kV 800mm 1.8m 2.2kV 300mm 700m Fault loops shall be installed in the joint or terminating pits or chambers, in such a way as to ensure that the minimum bending radius of the cable specified by the manufacturer is not compromised. Fault loops at the base of terminations on structures shall not involve the crossing of cable so that the cable length can be pulled through without twisting and should be installed as shown in Figure 4. Fault loops on either side of joints may contain loops and may be installed similarly to the illustrations in Figure 1, Figure 2 and Figure 3. PRINTOUT MAY NOT BE UP-TO-DATE; REFER TO METRO INTRANET FOR THE LATEST VERSION Page 11 of 30

12 Figure 1: Typical Fault Loop Installations for Joints Sand Pit Plan Elevation Figure 2: Typical Fault Loop Installation for Joint Formed Pit Plan Elevation Figure 3: Typical Fault Loop Installation for Joint Formed Pit PRINTOUT MAY NOT BE UP-TO-DATE; REFER TO METRO INTRANET FOR THE LATEST VERSION Page 12 of 30

13 Additional length Sand pit Structure Conduit swept bend Figure 4: Typical Fault Loop Installation Sand Pit for Ground Entry from a Structure 7.7 Ground Entry Arrangements For the ground entry points of cable onto structures, the cable shall be placed in conduit at not less than 300mm above ground level. The conduit shall extend to a minimum depth of 1000mm before entering a sand pit for a fault loop and should utilise a swept bend. The effect of the conduit entry and associated sand pit (if present) shall be considered in the design of the structure s foundation. Cables and conduits above ground shall be mechanically protected in accordance with Clause 219(2) of the Electricity Safety (Installations) Regulations 2009 from a distance of 300mm below ground level to 2400mm above ground level. A sign in accordance with AS 1319 reading Danger - High Voltage shall be fixed to the mechanical protection such that it is easily read from ground level. PRINTOUT MAY NOT BE UP-TO-DATE; REFER TO METRO INTRANET FOR THE LATEST VERSION Page 13 of 30

14 Figure 5: Typical mechanical protection on 1500V mast Any exposed conduit shall either be UV stabilised, or protected by the application of paint. The paint shall be specified for use on PVC pipe, of colour N43: pipeline grey (AS 2007) and be applied as per the manufacturer s recommendation. The conduit shall be sealed at the top end with expanding foam to prevent the ingress of water or vermin. The conduit shall run directly to an adjacent pit. 8 Separation of Services Where a service has a standard or operator requirement that specifies a separation, both that requirement and the requirements of this standard must be met by using the greatest separation distance of the two. Communication cables installed near high voltage cables under this specification shall comply with the requirements of SAA HB 29 and AS/ACIF S009. Other relevant standards include VRIOGS for signalling cables, VRIOGS for communications pathways and TS-SP-013 for VicTrack communications cables. Where a service does not have a standard, the minimum separations specified within this standard shall be applied. Greater separation distances may be required in particular installations. The following should be considered as a minimum: PRINTOUT MAY NOT BE UP-TO-DATE; REFER TO METRO INTRANET FOR THE LATEST VERSION Page 14 of 30

15 Maintenance and safe working arrangements (Electrical Access Permits, Track Access, Confined Spaces, Manual Handling, etc.) Effects on cable ratings Risk of damage to adjacent services as a result of cable failure Risk of damage to cables as a result of failure of adjacent services Separation distances shall be taken from the nearest outer surfaces of a conduit, length of troughing or trunking. Separation Distance Figure 6: Separation Distance HV conduits, trunking or troughing shall be separated by a clear space of not less than 600 mm in any direction from adjacent utility cables or services unless approved otherwise by the relevant utility owner and maintainer. The above notwithstanding, where HV cables, conduits, trunking or troughing cross over or under other utility cables or services, they shall be separated by not less than 300 mm. 8.1 Underground Conduits Minimum separation between two HV conduits or an HV and an LV conduit, shall be 50mm except where the conduits are installed within the same bore. Where two HV cables run in parallel and provide redundancy, they shall have a minimum horizontal separation of 1000mm. Signal or Essential Services Power Distribution cables run in parallel and providing redundancy shall have a minimum separation of 3000mm. 8.2 Structure Mounted Conduits Minimum separation between two HV conduits or an HV and an LV conduit, shall be 50mm. Where two HV cables run in parallel and provide redundancy, they shall have a minimum separation of 1000mm, and should be mounted on a separate structure wherever possible. 8.3 Ground Level Troughing Signal or Essential Services Power Distribution ground level troughing shall have a minimum of 100mm separation from adjacent services or troughing. Signal or Essential Services Power Distribution HV cable may be installed within shared ground level troughing providing it is run within a separate permanent compartment to other services and in accordance with the requirements of adjacent services. The barrier between compartments shall be such that an HV cable fault will not cause failure of adjacent services. Where two HV cables run in parallel and provide redundancy, they shall not be installed within the same troughing. PRINTOUT MAY NOT BE UP-TO-DATE; REFER TO METRO INTRANET FOR THE LATEST VERSION Page 15 of 30

16 8.4 Metallic Trunking Signal or Essential Services Power Distribution metallic trunking shall have a minimum of 150mm separation from adjacent services or trunking. Signal or Essential Services Power Distribution HV cables shall not be installed within shared trunking. Where two HV cables run in parallel and provide redundancy, they shall not be installed within the same trunking, and should be installed on separate posts where possible. 9 Cable Pits and Chambers 9.1 Pit and Chamber Types Formed pits or chambers in accordance with section 9.3 are preferred for all installations except where the topology is such that the formed pit is unlikely to be able to drain appropriately and would result in cables and joints being submerged for long periods of time. Sand pits in accordance with section 9.4 may be utilised for HV cables for connection to underground conduits. They may be used only where the requirements of sections (location and clearance from other services) and (protection and marking) are able to be achieved. 9.2 Pit and Chamber Locations A pit or chamber shall be provided wherever a cable joint is required in a conduit route. Any bends where, according to the manufacturer s recommendations, installation of the cables requires use of rollers shall have a pit or chamber installed. A pit or chamber shall be provided at each transition between underground conduit, structure mounted conduit, ground level troughing or trunking, as well as adjacent to each point of entry to the ground or to a building. Pits or chambers shall also be provided at regular intervals of not more than 400m to facilitate ease of installation, maintenance and repair. Cable pits and chambers shall be installed wholly within the VicTrack rail reserve wherever practicable. The edge of cable pits and chambers shall be installed no closer than 3000 mm from the closest running rail. Cable pits and chambers shall be sited so as not to interfere with surface drainage. Communication cables, signalling cables and low voltage cables shall not occupy the same pits or chambers as HV cables. Each pit or chamber that contains a HV cable shall contain only cables that are at the same voltage. Where two HV cables run in parallel and provide redundancy, they shall be provided with separate pits or chambers. PRINTOUT MAY NOT BE UP-TO-DATE; REFER TO METRO INTRANET FOR THE LATEST VERSION Page 16 of 30

17 9.3 Formed Pit and Chamber Requirements General Formed cable pits or chambers shall generally be of the reinforced concrete preformed type in accordance with AS Signal Power or Essential Services Distribution HV cable pits or chambers may be of plastic construction in accordance with the requirements of VRIOGS Cable pit covers shall comply with AS Pit covers shall be designed to allow ease of removal manually and shall be sectioned as necessary to limit the maximum weight to comply with Victorian Occupational Health and Safety Regulations. For access roads the pit covers shall be Class D (areas open to heavy-duty commercial vehicles) and for footpaths the pit covers shall be Class C (areas open to slow moving medium-duty commercial vehicles). Pits in other areas shall have pit covers installed of a class appropriate to the expected loading. Pit covers shall be designed to resist the ingress of water and be vermin proof. Pits shall be designed such that workers can access any conduits, cables or joints within the pit, generally requiring a chamber of sufficient size to enable a person to stand within the pit and work comfortably, and to accommodate the cable supports, cable joints, pulling mechanisms and spare cable lengths as may be required whilst ensuring the minimum bending radius is adhered to Pit or Chamber Size Pits shall be designed to be an appropriate size for their intended use, taking into consideration the cable bending radius requirements, conduit entry and exit locations, any requirement for fault loops and space to complete cable jointing. Typical pit sizes for some applications are shown in Table 4 below, however the suitability of these sizes for any particular application must be verified during design. Table 4: Typical Pit Sizes Application Length Width Essential Services Distribution System Joint Pit 2500mm 1500mm Essential Services Distribution System Turning Pit 1200mm 1200mm Essential Services Distribution System Pulling Pit 2000mm 1000mm High Voltage Distribution Joint Pit 4000mm 3000mm High Voltage Distribution Turning Pit 3000mm 3000mm 1500V DC Joint Pit 2000mm 1500mm 1500V DC Turning Pit 1200mm 1200mm PRINTOUT MAY NOT BE UP-TO-DATE; REFER TO METRO INTRANET FOR THE LATEST VERSION Page 17 of 30

18 9.3.3 Pit or Chamber Installation Cable pit and chamber covers and access covers are to be level with the surrounding finished surface in all areas subject to pedestrian or road traffic, e.g. platforms or access roads. For areas which are not subject to pedestrian or road traffic, the cable pit or chamber shall be 150 mm above the surrounding ground level to prevent the ingress of water and soil and shall be appropriately battered to the edge of the pit. Pits and chambers installed on unpaved slopes shall be installed level, and protected from being covered by retaining walls or appropriate landscape batters. Adequate drainage shall be provided for the pit or chamber. If it is impractical to discharge water seepage from the pit, a drainage sump shall be provided to allow for transfer of seepage to a decanting system Cable Entry Pits and chambers shall be of sufficient size to make cable joints. Joints in cables shall be arranged and supported in the pit or chamber in a manner which will provide for easy access to all joints for future maintenance purposes. Where conduit or ground level troughing enters a cable pit, the conduit or troughing shall be encased in concrete for a distance of 300 mm from the pit or chamber to hold the conduit or troughing securely in position. Any spare cable entries or conduits provided for future use shall be sealed to prevent the ingress of soil and water into the pit. Cable entries to pits or chambers should be tangential to the pit or chamber walls wherever practicable. Conduit entries shall be in the form of a bell mouth, smooth and free of sharp edges to prevent damage to the cable during installation and subsequent operation of the cable. The conduit entry shall be sealed with a suitable and approved expanding silicone or similar sealant. The lowest conduit shall be installed a minimum of 100 mm above the pit or chamber floor Cable Support Cables shall be supported within the pit by appropriately sized non-ferrous clamps mounted on structures fixed to the pit walls. The design of cable supports shall be such to ensure access as required by section is maintained, and the minimum bending radius of the cable is maintained. Typically small unistrut cantilevers would be provided for this purpose. All cable joints shall be supported at a height which ensures they are above the water table and will not be regularly submersed. PRINTOUT MAY NOT BE UP-TO-DATE; REFER TO METRO INTRANET FOR THE LATEST VERSION Page 18 of 30

19 9.3.6 Protection Figure 7: Cable Joint Supported in Pit Non-trafficable pits shall be protected by the installation of a minimum of two white posts, typically installed on diagonally opposite corners of the pit Pit Access If a pit requires steps or a ladder to provide a safe means of entry or exit due to being greater than 1m deep or the installation location, access steps or rungs complying with AS 1657 shall be provided. As far as practicable, pits shall be designed so that they are not considered as confined spaces. If this is not achieved, signage shall identify the pit as a confined space according to AS 2865 and shall be placed in a prominent position so that it is obvious to anyone intending to enter the pit. The signage shall be designed in accordance with AS 1319 Safety signs for the occupational environment. If required for entry and egress, anchorage points suitable for the attachment of two persons and complying with AS shall be provided with accompanying signage. 9.4 Sand Pit Requirements Location Requirements Sand pits shall be located a minimum of 5000mm clear of any VicTrack assets, 2000mm from any MTM services including adjacent HV conduits and a minimum of 3500mm from the nearest rail. Sand pits which breach these clearances may be installed only with the permission of the Head of Engineering Electrical. Existing sand pits may be reinstated. Sand pits shall be accessible to an excavator or small truck from a roadway or other access point without the vehicle fouling the track. Sand pits shall not be used within paved areas such as roadways or paths excavation of the sand pit shall not require the breaking and reinstatement of any pavement. PRINTOUT MAY NOT BE UP-TO-DATE; REFER TO METRO INTRANET FOR THE LATEST VERSION Page 19 of 30

20 9.4.2 Construction Sand pits shall be formed of an excavation of the natural earth to a minimum depth of 150mm below the lowest conduit or cable to enter within the pit. They shall be designed and sited such that they do not affect the stability of nearby structures. Sand pits should not be deeper than 1500mm, to allow ease of safe working within the pit. Conduits entering the pit shall extend a minimum of 150mm beyond the edge of the excavation, and be fitted with bell mouths to protect cables during pulling. Conduit ends shall be sealed after cable installation using an appropriate product such as an expanding foam to prevent ingress of sand, soil or water into the conduit. Fault loops within sand pits shall be laid on a flat horizontal plane and without crossings, as described in section 7.5. All cables and conduits within the sand pit shall be surrounded by a minimum of 150mm of clean sand in all directions. Sand within sand pits shall be compacted in layers of not more than 250mm using either a mechanical vibrator or hand tools. >1000 Fill Orange marker tape Concrete protection barriers Clean Sand > Protection and Marking Figure 8: Sand Pit Construction Sand pits shall be marked by the installation of four yellow posts installed at the corners of the pit. The yellow posts shall have cable route markers attached. Where the installation of marker posts is impractical, the pit may be marked by the provision of four monuments with cable route marker plates affixed, and a cable route marker nearby indicating the relative position of the pit. Sand pits shall be protected by concrete protection barriers installed 150mm above the cable or conduit. Such protection barriers shall be either polymeric cable protection covers to AS4702 or of concrete construction, a minimum of 40mm thick and with a characteristic strength in accordance with Australian Standards of not less than 15MPa at 28 days. PRINTOUT MAY NOT BE UP-TO-DATE; REFER TO METRO INTRANET FOR THE LATEST VERSION Page 20 of 30

21 The protection barriers shall be continuous (gaps of less than 50mm) and extend at least 50mm beyond the vertical line of any HV cable. Areas of the sand pit which do not contain cables do not require protection barriers. Orange warning tape to AS shall be installed in the pit backfill, approximately 300mm above the protection barriers. The warning tape within sand pits should extend 150mm beyond the vertical line of any HV cable. 10 Conduit 10.1 Conduit Requirements Conduit shall be rigid orange, PVC, heavy-duty type, as per AS 2053 or AS 1477 Class PN12. Exposed corrugated orange, heavy-duty type PVC may be used only for bends. For conduits installed by boring, polyethylene (PE) conduit to AS 4130 may be used. The minimum nominal conduit diameter shall be 100mm, or for 11kV or 22kV services, 150mm. Each conduit shall be sized for the number and installation conditions of the cables that are to be placed into it. One cable shall be installed in each conduit, except: Up to two parallel 1500V DC (of the same section) or Traction Negative cables may be installed in each conduit. Three cables comprising the three phases of one HV circuit may be installed in the same conduit. Two cables of the same circuit may be run in one conduit from the nearest pit to a ground entry arrangement. The internal diameter of the conduit should be greater than: 1.65 times the cable diameter for conduits containing a single cable 3 times the cable diameter for conduits containing two or three cables Conduit thickness should be assessed to ensure that under the expected loads including during construction, there will not be a loss of greater than 10% of the diameter of the conduit. Metal conduit shall not be used for HV cables under any circumstances Conduit Installation All conduit joints shall be made by utilising the spigot and socket ends. Ends to be joined shall be thoroughly cleaned using a solvent approved by the conduit manufacturer. The joint shall be impervious to water and shall be glued with an adhesive approved by the conduit manufacturer. Conduit shall be installed such that socket ends face the direction from which cables will be pulled. A draw wire of 6 mm diameter polypropylene blue/yellow or similar rope shall be placed in each conduit and suitably anchored at each end. Draw wires should have a minimum of 2m slack at each pit. PRINTOUT MAY NOT BE UP-TO-DATE; REFER TO METRO INTRANET FOR THE LATEST VERSION Page 21 of 30

22 10.3 Underground Installation The minimum depth from the finished ground level to the top of buried HV conduits shall be 1000mm at all times. Conduits entering formed pits shall slope away from the pit such that water does not flow into the pit. Conduits entering a building shall not allow water to flow into the building. Fill >1000 Marker tape Formed Pit Protection barriers Clean Sand Figure 9: Typical Pit Entry Conduit sloping away from pit During construction, and for conduits installed for future use, conduit ends shall be sealed using conduit end caps or an approved equivalent to prevent the ingress of dirt or sludge into the conduits. Conduits shall be cleaned and proven with an appropriately sized mandrel after installation, and test reports forwarded to MTM (see also section 16) Installation by Excavation The bottom of the cable trench shall be level across its width and free from any protrusions and rubble that could cause damage to the conduits. Changes in the trench gradient shall be gradual. The cable route shall, so far as possible, follow a constant grade and line. Rough and uneven ground shall be levelled to the extent necessary to achieve this objective. The bottom of the trench shall have 100mm of compacted clean sand. Buried conduits shall be surrounded by a minimum of 50mm of clean sand in all directions. Levelling work shall not adversely affect railway or natural drainage, or pedestrian or vehicular access routes. Cables shall be placed within trenches such that cable voltages increase with depth. No cable shall run below another cable with a higher voltage. Conduit routes shall be designed and constructed such that they do not affect the stability of nearby structures. PRINTOUT MAY NOT BE UP-TO-DATE; REFER TO METRO INTRANET FOR THE LATEST VERSION Page 22 of 30

23 Orange Warning Tape Fill > Clean sand >100 ~300 Protection barriers >50 HV Conduits > Bored Installation Figure 10: Buried Conduit Installation Conduits may be installed by boring only where required by circumstances on site such as under tracks, when crossing other services or roadways etc. Where conduits are installed by boring, the diameter of the bored hole should not exceed the outside diameter of the conduit or encasing pipe by more than 50mm. Where the diameter of the bored hole exceeds the outside diameter of the conduit or encasing pipe by more than 50mm, or where it is necessary to abandon a bored hole, the cavity or hole shall be promptly backfilled with approved materials such as an appropriate grout. The design and excavation of underground bores shall be such as to allow safe pulling of cables through the conduits, with the pulling arrangement to ensure no bending of cables in excess of the manufacturer s recommendations. PRINTOUT MAY NOT BE UP-TO-DATE; REFER TO METRO INTRANET FOR THE LATEST VERSION Page 23 of 30

24 Protection Conduits containing HV cables (except those installed by boring) shall be covered by protection barriers. Such protection barriers shall be either polymeric cable protection covers to AS4702 or of concrete construction, a minimum of 40mm thick and with a characteristic strength in accordance with Australian Standards of not less than 15MPa at 28 days. The protection barriers shall be continuous and extend at least 50mm beyond the vertical line of any HV conduit. Protection barriers should be installed approximately 150mm above the top-most HV conduit but may be installed higher if required due to the presence of other services. Protection barriers may be omitted for parts of a trench where other services provide a similar degree of coverage. An example is shown in Figure 11. Orange Warning Tape Fill >1000 ~300 Other Services Protection barriers >100 >150 Clean sand HV Conduits >50 Figure 11: Conduit Protection by Other Services For trenched conduit installations orange warning tape to AS shall be installed longitudinally in the trench backfill, approximately 300mm above the protection barriers (or highest other service) and shall extend at least 50mm beyond the vertical line of any HV conduit. PRINTOUT MAY NOT BE UP-TO-DATE; REFER TO METRO INTRANET FOR THE LATEST VERSION Page 24 of 30

25 10.4 Structure Mounted Installation Acceptable Usage Cases Structure mounted HV conduit shall only be installed with the approval of the Head of Engineering - Electrical on structures such as: On the underside of bridges Through deep cuttings with vertical concrete walls Beneath platforms Installation Requirements Structure mounted conduit shall be installed so as to maintain the minimum clearances as described in section 8. Conduit shall be permanently fixed to solid structures at regular intervals in accordance with the manufacturer s recommendations and shall be designed such that minimum bending radii of cables are respected. Structure mounted conduit shall be suitable for exposure to UV unless completely enclosed in a solid protective barrier or UV protected by the application of paint. The paint shall be specified for use on PVC pipe of colour N43: pipeline grey (AS 2007) and be applied as per the manufacturer s recommendation. The possibility of contact or damage by machinery working in the rail reserve shall be considered during design Protection and Labelling Structure mounted conduits, except those set in concrete, shall be labelled DANGER HIGH VOLTAGE at regular intervals of not more than 4m and at each change of direction. Structure mounted conduit shall be protected from access or accidental damage by a protective covering. The protective covering shall either consist of encasing concrete with a minimum thickness of 50mm, or an inflexible sheet. The protective covering shall either be solid, or shall be designed with a minimum rating of IP3X such that no body part (such as fingers) can come into contact with the installed conduit without removal of the covering. It shall be securely fastened to the same surface as the conduits, and shall be resistant to deformation from any forces that could reasonably be expected in normal circumstances (e.g. wind, persons leaning against screens, hail, etc.) If located in a publically accessible area, the protective covering shall either be padlocked in place or shall require special tools to be removed. The protective covering (including encasing concrete) must be signed with the words DANGER HIGH VOLTAGE at regular intervals of not more than 4m and adjacent to any change of direction Strength The cable installation system shall be designed to have adequate strength to support the static weight of the cable and covering, resist electromagnetic forces that may result during an electrical fault, and resist the forces that may result from thermal expansion of the cable and cable installation system. PRINTOUT MAY NOT BE UP-TO-DATE; REFER TO METRO INTRANET FOR THE LATEST VERSION Page 25 of 30

26 10.5 Spares For each set of conduits for a specific voltage level, a minimum of an additional 25% (rounded up to the nearest whole conduit) of the used conduits shall be installed as spare conduits. There is no requirement for spare conduit from a ground entry arrangement to the nearest pit. For example if five 1500V DC conduits, three 22kV AC conduits and one 2.2kV AC conduit are to be installed, an additional two conduits for 1500V DC cable, one conduit for 22kV AC cable and one conduit for 2.2kV AC cable shall be installed as spares. 11 Direct Buried Cable HV cables shall not be direct buried (except within sand pits for fault loops or cable joints where additional protection is supplied), so as to ensure maintainability and appropriately protect cables. 12 Ground Level Troughing and Trunking 12.1 Acceptable Usage Cases Ground level troughing and metallic trunking may be used only outside of publically accessible areas of the rail reserve. Use of ground level troughing or metallic trunking should be avoided for HV Cables and may be used only for Signal or Essential Services Power Distribution and only with the prior approval of the Head of Engineering Electrical. Appropriate usage cases may include crossings of culverts, watercourses, installation on bridges and short distances of up to 20m between pits or equipment cases Ground Level Troughing Ground Level Troughing installations shall be in accordance with the requirements of VRIOGS Rev. A with regards to Cable Route Type 5, except that troughing lids must be labelled with the words DANGER HIGH VOLTAGE. Troughing lids shall not be able to be opened without the use of tools. Only type approved Ground Level Troughing shall be used. Installation shall respect the minimum bending radius of cables Trunking Trunking installations shall be in accordance with the requirements of VRIOGS Rev. A with regards to Cable Route Type 6. Installation shall respect the minimum bending radius of cables. Insulated sections or air gaps ensuring 3kV insulation shall be installed within the metallic trunking every 500m, and on either side of any bridges or stations. Trunking shall not be fixed to any fences or overhead structures and shall be insulated from underbridges of concrete construction with ballasted track to a level of 3kV. No electrolysis, step or touch potential issues shall arise through the installation of trunking. Relevant standards such as MEST Railway Bridges Electrical Protection and Bonding shall be considered when the metallic trunking is being designed and the design shall be reviewed by the Office of the Chief Engineer to ensure appropriate bonding is included. PRINTOUT MAY NOT BE UP-TO-DATE; REFER TO METRO INTRANET FOR THE LATEST VERSION Page 26 of 30

27 13 Marking, Labelling and Record Keeping 13.1 Recording of Cable Routes and Cable Plans In accordance with Clause 218(3) of the Electricity Safety (Installations) Regulations, the installed route shall be recorded as accurately as practicable with a margin of error not exceeding 200mm. The northing and easting data shall be recorded at each change of direction of the cable route. Where there are existing MTM cables installed in the vicinity of the cable route, a consolidated cable plan shall be produced by either updating or superseding the existing plan(s) in compliance with the PTV Infrastructure Drafting Standard. As constructed cable plans shall be provided for the entire cable installation and in accordance with AS 4799 and the PTV Infrastructure Drafting Standard. The cable plans shall include one or more cross sections at crossings and representative locations showing the installed cable, conduit, trunking or troughing in relation to other cables, conduits and features such as tracks. It shall be possible to readily identify the path of each individual conduit in both cross section and plan view if the cross section alters through the route. Additional cross sections shall be provided to enable this identification. GPS co-ordinates shall be recorded every ten metres for the entire length of the cable route / trench, and at all changes of direction. This method shall also be utilised to capture all: Cable joint locations. Cable pit locations. Under line crossings Under road crossings Changes of direction Spare Conduits Other significant points of the cable route 13.2 Cable Route Markers Markers shall be provided at the location of all underground cables in accordance with AS The markers shall be manufactured, mounted and installed as shown in standard drawings STD_E0169 and STD_E0170. The marker plates shall be fixed to the post by means of construction adhesive or appropriate permanent fixing such as riveting. In the rail corridor markers shall be located above underground cables at: Points of entering and leaving the rail corridor; Each point where the route changes direction by more than 5 ; Not greater than 100 m intervals along the route such that at least two markers shall be visible at any point along the route; Markers shall not obstruct vehicle access along the side of the track or infringe structure gauge. In yard areas they shall not obstruct footpaths, walkways, vehicle access ways, lighting or other railway assets. Markers for conduit routes shall be mounted on white posts, and markers for sand cable pits shall be mounted on yellow posts. PRINTOUT MAY NOT BE UP-TO-DATE; REFER TO METRO INTRANET FOR THE LATEST VERSION Page 27 of 30

28 13.3 Cable Labelling All installed High Voltage Cables shall be legibly and indelibly marked with an appropriate identifying label at each end of the cable, and at any cable joints. The label shall be designed to maintain legibility in the installation conditions for twice the design life of the cable. A suitable label is a stainless steel stamped type, fixed to the cable with appropriately sized and tensioned black nylon cable ties. The label shall state the destination points of the cable and the name of the cable relevant to appropriate drawings. For example: Section 111/1 (cable 2) Structure 836 to Caulfield Substation 22/17/1 Caulfield Substation to Structure kV Feeder 1GR104 to 3GR106 Each cable shall be uniquely labelled Pit Marking Formed pit covers shall be labelled with the words DANGER - Railway High Voltage on their outer surface. The labelling should be engraved or embossed and permanently affixed such that it will remain readable despite expected weathering. Each pit containing High Voltage Cables shall be marked with an engraved label which includes the pit number and relevant drawing number. For formed pits these shall be fixed to the pit cover. For sand pits, these shall be fixed to one or more of the surrounding yellow marker posts. 14 Construction 14.1 Qualification All electrical installation work shall be carried out by licenced persons as prescribed by section 38 of the Electricity Safety Act Electrical installation work as defined by the Act includes the laying of conduits and the pulling of cables. Contractors engaged for the installation of cable routes and cables shall be appropriately qualified and experienced and shall be approved by the Head of Engineering - Electrical in advance General The Constructor shall be responsible for the identification and location of all buried services and shall comply with the Protection of Underground Assets and Services Procedure (L1- INF-PRO-001) as well as the Maintaining Track Integrity procedure (L2-TRK-PRO-032). The Constructor shall mark the location of all existing cables, drainage and all other underground services of other authorities in the area to be excavated. When trenching in the vicinity of gas, water mains or service utility lines, the Constructor shall comply with any restrictions which may apply to the easement and liaise with the owners of that easement to establish mutually agreed methods of protection and support for the services. PRINTOUT MAY NOT BE UP-TO-DATE; REFER TO METRO INTRANET FOR THE LATEST VERSION Page 28 of 30

29 Where Pits are to be located within existing pathways, roadways or access areas, the Constructor shall maintain continuous access in compliance with current MTM standards throughout construction. The Constructor shall reinstate any roadways, pathways or access areas to current MTM or relevant asset owner standards after construction. Any affected surface drains shall be reinstated by the Constructor. Any excess spoil not utilised in backfilling must be removed from site by the Constructor unless approval is given by MTM for an alternative arrangement. Damage to any service during construction activities shall be the total responsibility of the Constructor. All conduits are to be stored undercover, protected from direct sunlight while keeping a moderate temperature. Plastic sheeting shall not be used as a protection cover as it may increase the temperature of the conduit and potentially damage its integrity Fill and Compaction Backfilling and compaction shall be undertaken in accordance with the requirements of VRIOGS clauses 6.15 and Installation in Tunnels All cables installed in tunnels (including the MURL) shall not emit toxic combustion products, shall be classified as low smoke, low toxicity and halogen free, and tested in accordance with Australian Standards. In tunnels, PVC conduits shall not be used unless embedded in concrete. An alternative cable mounting system approved by the Head of Engineering - Electrical shall be used. 16 Inspection and Testing Inspection and Test Plans shall be prepared and submitted to MTM for approval, which must be granted prior to construction commencing. Provision shall be made for inspection of cable routes by MTM representatives prior to backfilling. An MTM representative shall be invited to witness various tests as appropriate. 10 working days notice shall be given of the intention to carry out works for which witnessing may be required Conduit Testing Testing shall include mandrel testing of underground conduit installations as required by section An MTM representative shall be invited to witness this testing The mandrel shall be solid, have diameter not more than 12mm smaller than the internal diameter of the conduit and be a minimum 230mm in total length and 130mm in flat length. It shall be pulled through every conduit in both directions by hand or with a machine to ensure their integrity. PRINTOUT MAY NOT BE UP-TO-DATE; REFER TO METRO INTRANET FOR THE LATEST VERSION Page 29 of 30