EDF Energy LV Service Cable Joints

Document Number: EI 02-0019
Date: 03/11/2005
ENGINEERING INSTRUCTION
EI 02-0019
INSTALLATION OF UNDERGROUND CABLES - LV TO 132KV
Network(s):
EPN, LPN, SPN
Summary:
This engineering instruction details the minimum requirements acceptable for the
installation of new LV, 11kV, 20kV, 33kV, 66kV and 132kV cables, plus associated
pilot and telephone cables.
Originator:
Paul Williams
Date:
03/11/2005
Approved By:
Paul Eaves
Approved Date:
03/11/2005
Review Date:
03/11/2008
This document forms part of the Company’s Integrated Business System and its requirements are mandatory throughout EDF
Energy Networks Branch. Departure from these requirements may only be taken with the written approval of Asset
Management. If you have any queries about this document please contact the originator of the current issue.
Document History
(The document history notes below are intended as a guide only and may not cover all of the changes. If you wish to make use
of this document it should be read in full.)
Version
Date
Details
Originator
06
24/10/2005
Re-written for all EDF Energy networks
Paul Williams
CABLE JOINTS, CABLE TERMINATIONS, CABLE GLANDS, CABLE CLEATS
FEEDER PILLARS, FUSE LINKS, ARC FLASH, CABLE ROLLERS, CUT-OUTS
11KV 33KV CABLE JOINTS & CABLE TERMINATIONS
FURSE EARTHING
www.cablejoints.co.uk
Thorne and Derrick UK
Tel 0044 191 490 1547 Fax 0044 191 477 5371
Tel 0044 117 977 4647 Fax 0044 117 9775582
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THIS IS AN UNCONTROLLED DOCUMENT, THE READER MUST CONFIRM ITS VALIDITY BEFORE USE
Version: 06
Installation of Underground Cables - LV to 132kV
Document Number: EI 02-0019
Version: 06
Date: 03/11/2005
Contents
1
Scope ..........................................................................................................................4
2
References..................................................................................................................4
3
General Requirements...............................................................................................4
4
On Site Requirements................................................................................................4
4.1
Street Works ............................................................................................................... 4
4.2
Plans and Records...................................................................................................... 4
5
Cable Types for New Installations ............................................................................5
5.1
Direct Buried Installations ........................................................................................... 5
5.1.1
LV Service Cables....................................................................................................... 5
5.1.2
LV Mains Cables ......................................................................................................... 5
5.1.3
11kV Cables................................................................................................................ 6
5.1.4
20kV Cables................................................................................................................ 6
5.1.5
33kV Cables................................................................................................................ 6
5.1.6
66kV Cables................................................................................................................ 7
5.1.7
132kV Cables.............................................................................................................. 7
5.1.8
Auxiliary Multi-core and Multi-pair cables.................................................................... 7
5.2
In Air Installations........................................................................................................ 7
5.2.1
LV Service Cables....................................................................................................... 7
5.2.2
LV Mains Cables ......................................................................................................... 8
5.2.3
11kV Cables................................................................................................................ 8
5.2.4
20kV Cables................................................................................................................ 8
5.2.5
33kV Cables................................................................................................................ 9
5.2.6
66kV Cables................................................................................................................ 9
5.2.7
132kV Cables.............................................................................................................. 9
5.2.8
Auxiliary Multi-core and Multi-pair cables.................................................................... 9
5.3
Joint Bays.................................................................................................................... 9
6
Cable Installation Depths ..........................................................................................9
6.1
Low Voltage Service and Mains Cables.................................................................... 10
6.2
11 and 20kV Cables.................................................................................................. 12
6.3
33kV Cables.............................................................................................................. 14
6.4
66 and 132kV Cables................................................................................................ 16
6.5
Auxiliary Multi-core and Multi-pair Cables ................................................................. 18
6.6
Typical Trench Layouts ............................................................................................. 18
7
Cable Installation .....................................................................................................23
7.1
Trench Bedding......................................................................................................... 23
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7.2
Cable Ducts............................................................................................................... 23
7.3
Cable Drums ............................................................................................................. 23
7.4
Pulling Cable ............................................................................................................. 24
7.5
Blinding Cables ......................................................................................................... 25
7.6
Cable Protection Covers ........................................................................................... 25
8
Trenchless Installation ............................................................................................25
8.1
General ..................................................................................................................... 25
Appendix A – Cable Maximum Pulling Tensions ..............................................................27
A.1
Maximum cable pulling tensions, minimum duct dimensions and minimum bending
radii for LV and 11KV Cables.................................................................................... 27
A.2
Maximum Cable Pulling Tensions and Minimum Bending Radii for 20kV Cables .... 27
A.3
Maximum Cable Pulling Tensions and Minimum Bending Radii for 33kV Cables .... 28
A.4
Maximum Cable Pulling Tensions and Minimum Bending Radii for Multi-core and
Multi-pair Cables ....................................................................................................... 28
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Document Number: EI 02-0019
Version: 06
Date: 03/11/2005
1
Scope
This Engineering Instruction covers the minimum requirements for the installation of new low
voltage, pilot and telephone, 11kV, 20kV, 33kV, 66kV and 132kV cables and the types of
cable that shall be installed in particular operating environments.
2
References
This Engineering Instruction makes reference to the current issue of the following documents
at the time of tendering:
EDF Energy Documents
EDF Energy Distribution Safety Rules (DSR) & associated Codes of Practice
EI 02-0031
Protecting 11kV Cables and Joints installed in air from Fire and Mechanical
Damage
EI 09-0059
Street Works Management Policy
EI 09-0100
Process for the Site Recording of Cables, Plant and Equipment
ES 2-0526
Plastic Ducts for Buried Cables
ES 2-1000
Cable Protection Covers
SHE 101-WMS-01
Safety, Health & Environmental Specific Work Method Cable/Duct
Laying, Pulling
SHE 101-WMS-02
Safety, Health & Environmental Specific Work Method Excavation &
Streetworks
3
General Requirements
The general requirements of this Engineering Instruction are as follows:
a) Guidance on the types of cable that shall be installed in different operating environments;
b) Minimum acceptable depths of cover for all types of new cable;
c) Installation guidelines for new cables and cable ducts;
d) Installation guidelines of new cable marker tape and stokboards;
4
On Site Requirements
4.1
Street Works
All staff and subcontractors employed to carry out the works described in this engineering
instruction shall comply with the requirements of EI 09-0059 EDF Energy’s Street Works
Management Policy.
4.2
Plans and Records
On completion of all works as-built drawings shall be provided as laid down in EI 09-0100
EDF Energy’s process for the Site Recording of Cables, Plant and Equipment.
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5
Cable Types for New Installations
5.1
Direct Buried Installations
Only the following types of cable shall be permanently installed either directly in the ground
or in cable ducts:
If it is necessary to install any of these types of cable in an in-air environment (i.e. a cable pit
or cable basement), for short distances, it shall be protected with one of the methods
described in Engineering Instruction EI 02-0031 Protecting 11kV Cables and Joints installed
in air from Fire and Mechanical Damage.
5.1.1
LV Service Cables
The following table details the sizes and types of Concentric and Split Concentric cable with
black PVC sheaths that shall be used in direct buried or ducted situations:
Cable Type
Conductor Size
EDF Energy SAP Commodity
Code
EPN
LPN
SPN
Single Phase Concentric
4 mm2 Copper
N/A
05160G
05860K
Single Phase Concentric
2
05574K
N/A
N/A
2
05455U
05176Y
05886L
2
05602M
05177J
05903U
Single Phase Concentric
Three Phase Concentric
Single Phase Split Concentric
5.1.2
16 mm Aluminium
35 mm Aluminium
35 mm Aluminium
2
25 mm Copper
05884R
LV Mains Cables
The following table details the sizes and types of Waveform cable with a black PVC sheath
that shall be used in direct buried or ducted situations:
Cable Type
Conductor Size
EDF Energy SAP Commodity
Code
EPN
LPN
SPN
Three Phase Waveform
95 mm2 Aluminium
05577P
05150X
05577P
Three Phase Waveform
185 mm2 Aluminium
05579J
05151H
05906Y
05599H
05152S
05907J
Three Phase Waveform
2
300 mm Aluminium
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5.1.3
11kV Cables
The following table details the sizes and types of Triplex and Single Core XLPE cable with a
red Polyethylene outer sheath that shall be used in direct buried or ducted situations:
Cable Type
Conductor Size
EDF Energy SAP Commodity
Code
95 mm2 Aluminium
Triplex
06000B
2
06001L
2
06002V
2
300 mm Copper
06003F*
Single Core
2
400 mm Copper
06020T*
Single Core
2
500 mm Copper
06021D*
Single Core
630 mm2 Copper
06022N*
Single Core
2
06023X*
Triplex
185 mm Aluminium
Triplex
300 mm Aluminium
Triplex
800 mm Copper
* Available as a non-stock item from EDF Energy Supply Chain.
5.1.4
20kV Cables
The following table details the sizes and types of Triplex XLPE cable with a red Polyethylene
outer sheath that shall be used in direct buried or ducted situations:
Cable Type
Conductor Size
EDF Energy SAP Commodity
Code
300 mm2 Copper
Triplex
06060D*
* Available as a non-stock item from EDF Energy Supply Chain.
5.1.5
33kV Cables
The following table details the sizes and types of Single Core XLPE cable with a red
Polyethylene outer sheath that shall be used in direct buried or ducted situations:
Cable Type
Conductor Size
EDF Energy SAP Commodity
Code
Single Core
185 mm2 Copper
06100J*
Single Core
2
300 mm Copper
06101T*
Single Core
400 mm2 Copper
06102D*
Single Core
2
500 mm Copper
06103N*
Single Core
630 mm2 Copper
06104X*
Single Core
2
06105H*
800 mm Copper
* Available as a non-stock item from EDF Energy Supply Chain.
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5.1.6
66kV Cables
Single core XLPE cables with a black Polyethylene outer sheath shall be used which fully
comply with EDF Energy Equipment Specification ES 2-0990. These are generally
purchased on a project by Project basis.
5.1.7
132kV Cables
Single core XLPE cables with a black Polyethylene outer sheath shall be used which fully
comply with EDF Energy Equipment Specification ES 2-4000. These are generally
purchased on a project by Project basis.
5.1.8
Auxiliary Multi-core and Multi-pair cables
Multi-core and Multi-pair cables with black PVC outer sheaths shall be used which fully
comply with EDF Energy Equipment Specification ES 2-0950. These are generally
purchased on a project by Project basis.
5.2
In Air Installations
Only the following types of cable shall be permanently installed in cable tunnels, cable
basements and other situation where the cable is exposed to the air:
In these situations cable joints should only be installed as a last resort, but if required these
shall be fitted with the appropriate flame retardant materials as detailed in EI 02-0031
Protecting 11kV Cables and Joints installed in air from Fire and Mechanical Damage.
5.2.1
LV Service Cables
The following table details the sizes and types of Concentric and Split Concentric cable with
an orange flame retardant sheath that shall be permanently installed in cable tunnels, cable
basements and other situation where the cable is exposed to the air:
Cable Type
Single Phase Concentric
Three Phase Concentric
Single Phase Split Concentric
•
Conductor Size
35 mm2 Aluminium
EDF Energy SAP Commodity
Code
05550D
2
05552X
2
N/A*
35 mm Aluminium
25 mm Copper
Available as a non-stock item from EDF Energy Supply Chain.
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5.2.2
LV Mains Cables
The following table details the sizes and types of Waveform cable with an orange flame
retardant sheath that shall be permanently installed in cable tunnels, cable basements and
other situation where the cable is exposed to the air:
Cable Type
Three Phase Waveform
Conductor Size
EDF Energy SAP Commodity
Code
95 mm2 Aluminium
05594C*
2
Three Phase Waveform
185 mm Aluminium
05595M*
Three Phase Waveform
300 mm2 Aluminium
05596W*
* Available as a non-stock item from EDF Energy Supply Chain.
5.2.3
11kV Cables
The following table details the sizes and types of Single Core XLPE cable with a red flame
retardant outer sheath that shall be permanently installed in cable tunnels, cable basements
and other situation where the cable is exposed to the air:
Cable Type
Single Core
Conductor Size
EDF Energy SAP Commodity
Code
95 mm2 Aluminium
06004Q
2
06005A
2
06006K
Single Core
2
300 mm Copper
06007U*
Single Core
2
400 mm Copper
06024H*
Single Core
2
500 mm Copper
06025S*
Single Core
2
630 mm Copper
06026C*
Single Core
2
06027M*
Single Core
Single Core
185 mm Aluminium
300 mm Aluminium
800 mm Copper
* Available as a non-stock item from EDF Energy Supply Chain.
5.2.4
20kV Cables
The following table details the sizes and types of Single Core XLPE cable with a red flame
retardant outer sheath that shall be permanently installed in cable tunnels, cable basements
and other situation where the cable is exposed to the air:
Cable Type
Triplex
Conductor Size
EDF Energy SAP Commodity
Code
300 mm2 Copper
* Available as a non-stock item from EDF Energy Supply Chain.
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06061N*
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5.2.5
33kV Cables
Single core XLPE cables with a red flame retardant outer sheath shall be used which fully
comply with EDF Energy Equipment Specification ES 2-0905. These are generally
purchased on a project by project basis.
5.2.6
66kV Cables
Single core XLPE cables with a black flame retardant outer sheath shall be used which fully
comply with EDF Energy Equipment Specification ES 02-0995. These are generally
purchased on a project by project basis.
5.2.7
132kV Cables
Single core XLPE cables with a black flame retardant outer sheath shall be used which fully
comply with EDF Energy Equipment Specification ES 02-0404. These are generally
purchased on a project by project basis.
5.2.8
Auxiliary Multi-core and Multi-pair cables
Multi-core and multi-pair cables with black flame retardant outer sheaths shall be used which
fully comply with EDF Energy Equipment Specification ES 02-0950. These are generally
purchased on a project by project basis.
5.3
Joint Bays
Where reasonably practicable, all exposed cables and joints in joint bays shall be blinded
with sand or covered with sand bags, before they are being energised, to protect them
against mechanical damage and to prevent the possible spread of fire.
In situations where this is not possible consideration should be given to the use of other
appropriate methods to protect cables, plant and equipment from fire damage, as detailed in
Engineering Instruction EI 02-0031 Protecting 11kV Cables and Joints installed in air from
Fire and Mechanical Damage.
For existing in air installation all joints should be protected with suitable flame retardant
materials, as detailed in EI 02-0031 Protecting 11kV Cables and Joints installed in air from
Fire and Mechanical Damage.
6
Cable Installation Depths
All cables shall be installed to the following minimum depths of cover, where the depth is
measured to the top surface of either the cable or the duct containing the cable.
In instances where these minimum depths cannot be achieved, the cables shall be installed
with additional mechanical protection, in the form of either ‘stokboards’, steel plates or ducts.
In this case, all steel plates shall be a minimum of 200mm wide and steel pipes shall be of
the same internal diameter as the plastic ducts, normally used for the type of cable to be
installed.
All steel plates and ducts shall be covered with EDF Energy Tile Tape to clearly identify that
cables have been installed below.
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6.1
Low Voltage Service and Mains Cables
All Low Voltage (LV) cables shall be installed to the following minimum depths, whether they
are laid direct or installed in suitable ducts:
•
Footways, grass verges or private property = 450mm;
•
Carriageways (including road crossings) = 600mm;
•
Normal agricultural land (not subject to deep ploughing) = 1050mm;
•
Agricultural land subject to deep ploughing = 1200mm.
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6.2
11 and 20kV Cables
All 11 and 20kV cables shall be installed to the following minimum depths, whether they are
laid direct or installed in suitable ducts:
•
Footways, grass verges or private property = 600mm;
•
Carriageways (including road crossings) = 750mm;
•
Normal agricultural land (not subject to deep ploughing) = 1050mm;
•
Agricultural land subject to deep ploughing = 1200mm.
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6.3
33kV Cables
All 33kV cables shall be installed to the following minimum depths, whether they are laid
direct or installed in suitable ducts:
•
Footways, grass verges or private property = 900mm;
•
Carriageways (including road crossings) = 900mm;
•
Normal agricultural land (not subject to deep ploughing) = 1050mm;
•
Agricultural land subject to deep ploughing = 1200mm.
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6.4
66 and 132kV Cables
All 66 and 132kV cables shall be installed to the following minimum depths, whether they are
laid direct or installed in suitable ducts:
•
Footways, grass verges or private property = 900mm;
•
Carriageways (including road crossings) = 900mm;
•
Normal agricultural land (not subject to deep ploughing) = 1050mm;
•
Agricultural land subject to deep ploughing = 1200mm.
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6.5
Auxiliary Multi-core and Multi-pair Cables
Auxiliary multi-core and multi-pair cables are usually laid at similar depths to the power cable
with which they are associated, the following minimum depths and conditions shall apply,
whether they are laid direct or installed in suitable ducts:
6.6
•
All normal methods of protecting the cables from damage (i.e., Tiletape and/or
“Stokboard”);
•
Footways, grass verges or private property = 450mm;
•
Carriageways (including road crossings) = 600mm;
•
Normal agricultural land (not subject to deep ploughing) = 1050mm;
•
Agricultural land subject to deep ploughing = 1200mm.
Typical Trench Layouts
When Cables of differing voltages are to be installed in a common trench all the minimum of
depths of cover detailed in section 6 of this engineering instruction shall be maintained.
Drawings DB/SD10/74/21 to DB/SD10/74/25 show a number of example installation for
guidance.
For clarity ducted installations are not shown, cables installed in ducts shall be installed to
the same standard except that the measurement for the minimum depth of cover is from the
final finished surface of the ground to the top surface of the duct.
Pilot and telephone cables installed alongside 11 and 33kV cable circuits shall normally be
installed at LV cable minimum depths of cover, unless operation reasons dictate that they
are laid at the same depth as the power cable.
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7
Cable Installation
7.1
Trench Bedding
All cables shall only be laid directly onto the bottom of the trench, if the surface is unlikely to
cause damage to the outer sheath.
Where a sand bedding material needs to be used for the base of a trench, the depth of the
trench shall be increased by the appropriate amount to ensure that the required minimum
depth of cover is achieved.
For 33, 66 and 132kV cable installations a selected sand bed, to a compacted depth of
75mm, shall be installed, covering the full width of the trench. The trench depth shall be
increased to ensure that the required minimum depth of cover is maintained.
7.2
Cable Ducts
Electricity, pilot and telephone cables shall only be installed into electricity cable ducts,
complying with EDF Energy equipment specification ES 02-0526.
New cable ducts shall be black in colour and marked with the legend 'Electric Cable Duct' on
two diametrically opposite sides.
Cable shall only be installed in ducts that are suitable sized to accommodate them, Appendix
A details the minimum internal duct diameters allowable for the most common types of cable
used by EDF Energy.
All cable duct joints shall be installed in accordance with the manufacturers' instructions or
recommendations and should be installed in such a way to prevent those damaging cables
as they are installed.
All cable ducts and tubes entering substations or buildings shall be sealed with the
appropriate Tyco Electronics ‘Rayflate’ duct seal to prevent the ingress of gas and water,
even if the ducts do not contain a cable.
Where reasonably practicable, before a cable is installed, all duct lines shall be checked and
cleared of all obstructions. To ensure that the duct is suitable for the type of cable to be
installed, a 3 metre length of the cable to be installed shall be pulled through the complete
length of duct. This shall then be examined for damage, before any attempt is made to install
the complete cable. If the sample of cable is found to have deep scores and tears in its outer
sheath, which are more than half the thickness of the outer sheath, the duct route shall be
repaired before any attempt is made to install the final length of cable.
EDF Energy may request for a specific job that ducts containing 33kV cables shall be filled
with a thermally stable re-enterable material. When such a material is used, the duct shall
be installed in a concrete surround and the joints in the pipe or duct shall be effectively
sealed to prevent the migration of the material and preserve its moisture content under
service conditions.
7.3
Cable Drums
Where reasonably practicable, before installing a cable, the delivered cable required for the
job shall be inspected to ensure that it is undamaged, the ends are sealed, and the correct
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size, length and voltage type required for the job has been delivered. Any damage or nonconformity shall be rectified immediately.
All cable drums shall be placed on firm and stable surface before the cable is removed. On
installation the cable shall always be pulled from the top of the drum to avoid damage.
Where it is necessary to move the drum into position the drum shall only be steered by the
use of purpose made slewing bars.
All cable jacks and spindles shall be checked to ensure that they are in good condition and
of the appropriate size for the weight of the drum and cable to be installed.
To avoid any risk of injury all nails shall be removed and made safe only once the drum is in
its final position.
All unused cable and other unused EDF Energy materials shall be stored safely and
securely on site and returned to the issuing depot as soon as is practical after the project or
project phase is complete. Cable drums shall be returned to the cable manufacturer, using
the free phone number displayed on the drum.
All non returnable cable drums shall be disposed of in accordance with the Environmental
Protection Act.
7.4
Pulling Cable
All cables shall be handled with care and installed as indicated in the manufacturer’s or EDF
Energy’s documentation. The cable shall be examined and checked for damage during and
immediately following installation. Any damage that occurs, no matter how small, shall be
reported immediately so the necessary repairs can be made.
Minimum cable bending radii shall be observed at all times and be as specified in Appendix
A. Sufficient labour and equipment to install the cable without causing damage to it or other
services shall be used at all times.
Cable shall only be laid when the ambient air temperature is above 0oC and has been so for
the previous 24 hours, or the cable has been stored in an environment where the
temperature has been maintained above 0oC, thus avoiding the risk of mechanical damage
during handling.
Where a winch is to be used it shall have a swivel eye fitted. The swivel eye must be in
good working order and able to freely rotate to prevent the cable twisting. The bond wire
must be pulled in from the far end and tensioned to ensure it does not damage other
apparatus crossing the trench.
Only serviceable winches shall be used to pull cable with an accurate dynamometer or an
adjustable tension limiting switch fitted. The maximum pulling force must not exceed the
values shown in Appendix A.
All pilot and telephone, LV, 11, 20, 33, 66 and 132kV cables shall normally be pulled in using
a correctly sized cable stocking which is securely fixed to the cable. More difficult pulls may
require the use of a pulling eye attached directly to the cable conductors.
Rollers shall always be used when pulling cables. All rollers used shall be in serviceable
condition moving easily on their spindle and with rolling surfaces free from damage.
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A leading roller shall be placed at the trench side at the pulling end, with slide rollers on
bends and hoop rollers along straight sections. Inverted skid plates shall be used to prevent
the cable or pull wire rising into obstructions. At duct entries a bell mouth shall be attached
at each end with rollers positioned to give central access into the bell mouth.
Immediately following installation of cables and/or their testing, the ends of each cable shall
be sealed against the ingress of moisture. Where more than one cable is being installed,
both ends of each cable shall be clearly identified by the use of numbered tapes or a similar
product.
7.5
Blinding Cables
Sand filled bags shall be used to support cables, joints or ancillary equipment when
necessary.
All accumulated water shall be pumped from the excavation before blinding the cable or
duct.
Following installation, all cables shall be blinded to a compacted depth of 100mm above the
cable or cable joint with soil taken from the excavated material or imported material. The
blinding shall be free from materials that may damage the cable.
Imported material for blinding (sand) shall only be used for cables 20kV or below if all the
excavated material is unsuitable.
All 33, 66 and 132kV cables shall be blinded either selected sand or cement bound sand to a
compacted depth of 100mm above the cable.
All blinding material over and around the cable and joint in joint bays shall be compacted by
hand.
7.6
Cable Protection Covers
Marker tile tape or Stokboards shall be installed over the cables as shown in the appropriate
trench drawings detailed in section 6 of this document. There is no requirement to install
either to approved ducts laid by hand or trenchless techniques, but may be installed if it is
deemed that additional protection is required.
All cables operating below 20kV laid direct both on public and private property shall be
marked and protected by a tile tape. This also includes all single-phase service cables with
a conductor size of 35mm2 or less, as well as pilot and telephone cables.
The tile tape shall be cut cleanly and installed so that it is overlaid at bends to provide
continuous cover to the cable route.
Only Stokboards shall be installed to protect 33, 66 and 132kV cables.
8
Trenchless Installation
8.1
General
All excavation and reinstatement work involved with trenchless methods shall be carried out
in accordance with this Engineering Instruction.
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Installation of Underground Cables - LV to 132kV
Document Number: EI 02-0019
Version: 06
Date: 03/11/2005
When the ground conditions are suitable, cables and ducts (up to 150mm internal diameter)
can be installed using trenchless installation techniques.
The entire cable or duct length shall be installed at a depth not less than the standard depth
appropriate to the cable operating voltage (section 6). Where, due to uplift forces, it is
necessary to install a cable or duct deeper than the standard depth, a cable or duct may be
installed at depth up to 10 times the outside diameter of the cable/duct.
All ducts and couplings shall comply with EDF Energy equipment specification ES 02-0526.
Duct lengths shall only be connected by either butt fuse or electro fuse welding. The method
used shall not reduce the internal diameter by more than 5mm.
A record of the route of the bored hole to indicate its position and depth shall be kept. The
marking of the route shall be carried out using only bio-degradable spray paint.
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Installation of Underground Cables - LV to 132kV
Document Number: EI 02-0019
Version: 06
Date: 03/11/2005
Appendix A – Cable Maximum Pulling Tensions
A.1
Maximum cable pulling tensions, minimum duct dimensions and minimum
bending radii for LV and 11KV Cables
Cable Size (mm2) & Type
Maximum
Pulling
Tension
Minimum
Duct
Internal
Diameter
Newtons
(kgf)
(mm)
Minimum
Bending
Radius
(mm)
LV Mains & Service Cables
4
1ph copper XLPE/PVC concentric
manual
32
75
16
1ph Aluminium XLPE/PVC concentric
manual
32
100
35
1ph Aluminium XLPE/PVC concentric
manual
32
125
35
3ph Aluminium XLPE/PVC concentric
manual
41
210
95
3ph Waveform
3000 (306)
100
550
185
3ph Waveform
7000 (714)
100
700
300
3ph Waveform
7000 (714)
100
850
600
Single core aluminium PVC/PVC
manual
125
350
740
Single core aluminium PVC/PVC
manual
125
400
11kV Mains Cables
95
Triplex Aluminium XLPE
8380 (855)
100
500
185
Triplex Aluminium XLPE
16300 (1665)
110
580
300
Triplex Aluminium XLPE
26475 (2700)
125
660
300
Triplex Copper XLPE
14700 (1500)
125
680
A.2
Maximum Cable Pulling Tensions and Minimum Bending Radii for 20kV
Cables
Cable Size (mm2) & Type
Maximum Pulling
Tension
Minimum Duct
Internal
Diameter
Minimum
Bending
Radius
(mm)
(mm)
Newtons (kgf)
20kV Mains Cables
300
Triplex Copper XLPE
14700 (1500)
150
1250
400
Triplex Copper XLPE
19600 (2000)
150
1350
27 of 28
Installation of Underground Cables - LV to 132kV
Document Number: EI 02-0019
Version: 06
Date: 03/11/2005
A.3
Maximum Cable Pulling Tensions and Minimum Bending Radii for 33kV
Cables
Cable Size (mm2) & Type
Maximum Pulling
Tension
Minimum Duct
Internal
Diameter
Minimum
Bending
Radius
(mm)
(mm)
Newtons (kgf)
33kV Mains Cables
185*
Single core Copper XLPE
9070 (925)
150
850
300*
Single core Copper XLPE
14700 (1500)
150
950
400*
Single core Copper XLPE
19600 (2000)
150
1050
500*
Single core Copper XLPE
19600 (2000)
150
1100
630*
Single core Copper XLPE
19600 (2000)
150
1200
800*
Single core Copper XLPE
19600 (2000)
150
1300
* In situations were three single core cables are pulled into a single duct using a single winch
the above maximum pulling tensions still apply.
A.4
Maximum Cable Pulling Tensions and Minimum Bending Radii for Multi-core
and Multi-pair Cables
Cable Size (mm2) & Type
Maximum Pulling
Tension
Minimum Duct
Internal
Diameter
Minimum
Bending
Radius
(mm)
(mm)
Newtons (kgf)
Multi-core and Multi-Pair Cables
4 pair - 0.8mm Multi-pair
2040 (208)
85
165
7 pair - 0.8mm Multi-pair
2620 (267)
85
185
19 pair - 0.8mm Multi-pair
5210 (531)
85
260
37 pair - 0.8mm Multi-pair
8940 (911)
85
340
61 pair - 0.8mm Multi-pair
13620 (1388)
85
420
4 core - 2.5mm Multi-core
1125 (114)
85
120
7 core - 2.5mm Multi-core
1462 (149)
85
140
12 core - 2.5mm Multi-core
2508 (255)
85
180
19 core - 2.5mm Multi-core
3530 (359)
85
215
27 core - 2.5mm Multi-core
4700 (479)
85
250
37 core - 2.5mm Multi-core
5710 (582)
85
275
CABLE JOINTS, CABLE TERMINATIONS, CABLE GLANDS, CABLE CLEATS
FEEDER PILLARS, FUSE LINKS, ARC FLASH, CABLE ROLLERS, CUT-OUTS
11KV 33KV CABLE JOINTS & CABLE TERMINATIONS
FURSE EARTHING
www.cablejoints.co.uk
Thorne and Derrick UK
Tel 0044 191 490 1547 Fax 0044 191 477 5371
Tel 0044 117 977 4647 Fax 0044 117 9775582
28 of 28
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