TRANSMISSION ENGINEERING STANDARD
TES-P-104.04, Rev. 0
TABLE OF CONTENTS
1.0
SCOPE
2.0
CABLES SPLICES
2.1
2.2
2.3
2.4
2.5
2.6
2.7
2.8
2.9
3.0
Definitions
Scope of Specifications and Drawings
General Requirements
Routing Cables
Connectors
Conductor Connections
Heat Shrinkable Splices - 600 Volts Through 35 kV
Phasing of Cable Splices
Cable End Caps
CABLE TERMINATIONS
3.1
3.2
3.3
3.4
3.5
3.6
General
Precautions in Making Cable Terminations
Locating Cable Terminations
Grounding of Cable Terminations
Partial Discharge Measurement
Elbow Terminations
TESP10404R0/YM
Date of Approval: December 16, 2006
PAGE NO. 2 OF 9
TRANSMISSION ENGINEERING STANDARD
1.0
TES-P-104.04, Rev. 0
SCOPE
This standard has been prepared as a guide for the splicing & termination of insulated
cables with copper or aluminum conductor that will be used for 0.6/1, 11, 13.8, 33,
34.5, 69, 110, 115, 132, 230 and 380 kV underground cables circuits in the system of
Saudi Electricity Company (SEC) Saudi Arabia.
1.1
2.0
General Requirements
1.1.1
All splices & terminations shall meet the requirements of applicable
Saudi Electricity Company Material Standard Specification (12TMSS-10), IEEE-48, IEEE-404 and in strict compliance with
manufacturer’s instructions.
1.1.2
The cables shall also meet the standards of SASO, AEIC, ICEA, IEC
and/or any other internationally recognized organizations.
1.1.3
The high voltage cable terminations shall be installed in a
professional manner with acceptable workmanship. Before
commencement of work all cable splicing and terminating personnel
shall obtain certification (from manufacturer or SEC) valid for a
period of not more than one year from the date of issue stating that
the person has been trained and is capable of accomplishing the task.
1.1.4
All GIS terminations shall be done under manufacturer’s supervision
and instruction, based on GIS termination drawings and installation
instructions which shall be submitted to SEC for review and
acceptance prior to starting the termination work. Personnel carrying
out the terminations shall posses certificate from mother company
and/or by an independent agency valid for a period of not more than
one year from the date of issue.
1.1.5
The cables splicing and terminating operation shall be performed in a
manner to mitigate the adverse effects of the environmental
conditions specified in 01-TMSS-01.
CABLE SPLICES
2.1
Definitions
The term "Cable Splice" as used in these specifications refers to all splices,
solid taps and branches in insulated power cable as may be made in man holes,
hand holes, splice boxes, vaults, tunnels, etc. This term does not apply to
splices for pulling into ducts.
The various types of cable splices referred to in this section are defined as
follows:
TESP10404R0/YM
Date of Approval: December 16, 2006
PAGE NO. 3 OF 9
TRANSMISSION ENGINEERING STANDARD
TES-P-104.04, Rev. 0
Straight Splice:- A splice between two cables having the same number of
conductors.
"Y" Splice:- A splice for connecting one cable to two cables, all of which have
the same number of conductors.
2.2
Scope
This section covers various types of cable splices for all types and sizes of
insulated cable commonly used by SEC for high and low voltage power
transmission.
Cable splices, not covered here shall be made according to the cable
manufacturer's recommendations and design.
2.3
General
In making cable splices, the the splicer and/or terminator must be certified by
manufacturer or SEC or an independent agency and shall specifically follow
this section and the manufacturer's recommendations for the particular splice
and type of cable being installed.
Splicing power cables requires great care in the assimilation of manufacturer's
instructions, utilizing prescribed materials with proper tools and above all,
observing extreme cleanliness in all phases of the splicing operation. The
cutting of the cable for splices also requires the observance of exact
dimensions - length and depth in the preparation of the cable for the splicing
procedure. The operation should be carried out in a proper dust free tent where
humidity and temperature are controlled as per manufacturer's
recommendations.
The removal of the semi-conducting layers over the conductor and the
insulation should be executed in a manner prescribed in the manufacturer's
instructions for each splice.
Similar recognition should be applied in the removal of the conductor,
insulation and jacket.
Unless otherwise permitted by SEC, all splicing operations shall be conducted
in a double walled tent equipped with a positive pressure type air conditioning
unit. The air conditioning unit shall be capable of maintaining the relative
humidity below 40%.
2.4
Routing Cables
Route the cables into their final positions, avoiding sharp bends and allowing
the ends to overlap. The overlap for splicing power cable should equal the
length of the completed splice. Also, it is desirable to have at least 150 m of
straight cable beyond ends of finished splice.
TESP10404R0/YM
Date of Approval: December 16, 2006
PAGE NO. 4 OF 9
TRANSMISSION ENGINEERING STANDARD
2.5
TES-P-104.04, Rev. 0
Connectors
Connectors for use in splicing shall be either compression or thermite welded
types in accordance with the manufacturer's specific recommendations.
2.5.1
Compression connectors shall be suitable for aluminum or copper
conductors. All connectors 35 mm2 and above shall have tapered
ends and metal barriers. Tapered ends will ease tape splicing and
alleviate stress points on high voltage splices.
2.5.2
Solder type connectors shall not be used with solid dielectric cables.
2.5.3
When splicing copper to copper conductors, only copper connector
shall be used.
2.5.4
When splicing aluminum to aluminum, only copper-aluminum or
aluminum rated connectors shall be used.
2.5.5
When splicing copper to aluminum conductors, only copper
aluminum rated connectors shall be used.
2.6
Conductor Connections
2.6.1
Preparation of Conductors
The normal procedure for cleaning exposed bare conductor ends prior to
installing connectors is brushing the surface of the conductor with a steel brush
until it is clean and bright. When cleaning aluminum conductor for
compression connections, it is necessary to apply an SEC approved inhibitor
compound to the exposed conductors immediately after the wire brushings.
The inhibitor compound will prevent the formation of a non-conductive film of
oxide on the conductor surface, which would otherwise form as a result of the
chemical reaction between the aluminum surface and air.
2.6.2
Application of Compression Connectors
Care shall be taken always to select the recommended compression
die for pressing the joint connector. It shall be installed in strict
compliance with manufacturer's instructions for applying
compression connectors.
2.6.3
Preparation of Cable Joint Surfaces
After the cable joint connector is installed and prior to applying the
insulation tape, or heat shrink material, the surfaces of the insulation
and insulation shield must be thoroughly cleaned with a SEC
approved cleaning fluid. The use of benzine, or gasoline, for this
purpose, is not permitted.
TESP10404R0/YM
Date of Approval: December 16, 2006
PAGE NO. 5 OF 9
TRANSMISSION ENGINEERING STANDARD
2.7
TES-P-104.04, Rev. 0
Heat Shrinkable Sleeve
Heat shrinkable polyethylene provides a recommended method for insulating
underground splices for XLPE cables (600 V to 35 kV). If the manufacturer's
splice kit does not include a heat shrinkable sleeve to protect the concentric
neutral wires against corrosion, then one shall be installed.
2.8
Phasing of Cable Splices
When the cable splices are installed for the purpose of circuit expansion or
repair, the cables to be spliced shall be identified and labeled to correspond
with phase indentification at the source side of the cable termination. Splicing
of the cables in accordance with proper phase identification will eliminate the
possibility of the splice introducing an out-of-phase condition in the circuit.
2.9
Cable End Caps
During the period that cables have been placed in ducts or trenches, and are to
be spliced at a later time, the cable ends are to be sealed to eliminate moisture
entering and corroding the cable conductor.
Heat shrinkable caps, shall be utilized and installed on open ends of the cables
in order to maintain the integrity of the cable.
2.10
Partial Discharge Test
Partial discharge measurements shall be carried out for high voltage cable 230
kV & 380 kV at site after completion of splicing/jointing of the cable to detect
the weak points. The tests shall be carried out preferably during the HV test or
immediately thereafter.
3.0
CABLE TERMINATIONS
3.1 General
3.1.1
Definitions
The term "Cable Termination" as used in this Section refers to all
terminations of insulated power cable in order to effect an electrical
connection to the cable conductor.
In its simplest form, a cable termination may be formed by attaching
a suitable terminal lug to the end of a cable conductor. For insulated
power cable, however, it is necessary to remove a section of the outer
jacket and shielding (if applicable), to seal the cable end against the
entrance of moisture, as well as provide a suitable electrical
termination of the cable insulation shield by means of a stress cone.
The method of sealing the cable end varies with the style of cable
termination.
TESP10404R0/YM
Date of Approval: December 16, 2006
PAGE NO. 6 OF 9
TRANSMISSION ENGINEERING STANDARD
3.1.2
TES-P-104.04, Rev. 0
Taped Termination
A taped cable termination is one in which the cable end is sealed by
the application of suitable insulating tape. Taped terminations of
power cables over 5 kV shall require the construction of a stress cone
by building up the proper shape through consecutive layers of tape.
3.1.3
Premolded and Molded Terminations
A premolded termination may be one of several types of slip on
terminations constructed of rubber like synthetic materials or a
combination of plastics and polymers. Terminations in this category
include skirted one-piece terminations with varying creep distances,
or elbow type of separable connections.
The application of premolded and molded terminations shall be
performed in strict compliance with the manufacturer's installation
procedures.
3.1.4
Heat Shrink Terminations
Heat shrink irradiated polyethylene is used to control terminal stress
and provide a means of terminating 15 kV, 35 kV, 69 kV, 110kV, 115
kV, 132 kV, 230 kV and 380 kV cables, indoor and outdoor.
The application of heat shrink irradiated polyethylene shall be
performed in strict compliance with the manufacturer's installation
procedures.
3.1.5
Porcelain Terminations
Indoor and outdoor porcelain terminations are used for 69-380 kV
rated cables, and shall be installed in strict compliance with the
manufacturer's procedures.
3.1.6
SF6 Gas-Immersed Terminations
SF6 Gas-Immersed terminations are used up to 380 kV rated cables,
and shall be installed in strict compliance with the manufacturer's
procedures.
3.1.7
Terminal Lugs
Terminal lugs used for all cable terminations must be selected to
insure the compatibility of the metal to metal contact. Where cables
with aluminum conductors are to be terminated on copper bus, such
as transformers or switchgear or on overhead copper line hardware,
the terminal lug shall be rated copperaluminum. An oxide inhibitor
TESP10404R0/YM
Date of Approval: December 16, 2006
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TRANSMISSION ENGINEERING STANDARD
TES-P-104.04, Rev. 0
shall be applied to the aluminum conductor prior to compressing the
terminal lug.
3.1.8
Leakage Distance
For outdoor terminations, the leakage distance shall be a minimum of
40 mm/kV line-to-line and 50 mm/kV near the coastel area
(preferably with High Voltage Insulator Coating (SYLGARD) for
coastal/polluted areas).
3.2
Precautions in Making Cable Terminations
In making cable terminations, the splicer and/or terminator must be certified by
an independent agency and shall specifically follow the specifications, details,
dimensions given on the manufacturer's drawings for the particular termination
and type of cable being installed.
Extreme care shall be taken in every step from start to finish to keep the cable
termination free from moisture, dirt, particles of metal and air pockets. To
accomplish this, the technician's hands, tools, containers and supplies must be
kept clean, dry and free from foreign matter at all times.
Do not expose unpacked premolded insulating materials to the atmosphere for
more time than absolutely necessary (as suggested by the manufacturer).
After the cable insulation has been exposed by removal of any section of the
outer covering, operations should be continued without interruption until the
cable termination is complete. Should it be necessary to leave an incomplete
cable termination overnight, the exposed cable insulation shall be protected by
a carefully applied covering of tape of the final type to be applied to the
termination and, in damp locations, this tape shall be covered by a waterproof
rubber or plastic tape. Suitable protection (depending on moisture and dirt
conditions and the voltage of the termination being made up) shall also be
applied to exposed insulation when terminating is interrupted for eating time or
for necessary tests.
The permanent storage of cable termination shall be strictly as per manufacturer
recommendations
3.3
Locating Cable Terminations
3.3.1
Locating Terminations
Cable terminations are frequently attached directly to the equipment
terminals, buses or other conductors. This application determines to
an appreciable extent, the location of the termination. However, there
may be some choice with regards to the direction from which the
cable approaches the termination. The cable shall be so arranged as
to permit locating the last cable support close to the termination. This
will avoid putting undue strains on the equipment terminals or the
TESP10404R0/YM
Date of Approval: December 16, 2006
PAGE NO. 8 OF 9
TRANSMISSION ENGINEERING STANDARD
TES-P-104.04, Rev. 0
terminal lugs on the cable. Usually, such terminal supports shall be
located 600-900 mm from the equipment terminals. Terminal
supports shall be so located that no sharp edges are made on the cable
and no bend occurs in the taped portion of the cable termination.
3.4
Grounding of Cable Terminations
3.4.1
General
Metal parts of terminating devices, concentric neutral copper, tinsel
braid or other metallic shielding on stress cones in cable terminations
shall be effectively grounded to the system ground. These various
components usually are bonded together within the cable termination
so that a single grounding connection serves to ground the complete
termination. However, precautions must be taken to make sure that
all parts of a termination requiring grounding are properly connected
together.
An exception is when, on occasion, the open end of a single point
grounded section of circuit is terminated. Special provisions will be
required to isolate the cable shield or concentric neutral from the
ground potential of metal parts of the terminating rack or device.
3.5
Partial Discharge Measurement
Partial discharge measurements shall be carried out for high voltage cable 230
kV & 380 kV at site after completion of termination of the cable to detect the
weak points. The tests shall be carried out preferably during the HV test or
immediately thereafter.
3.6
Elbow Terminations
3.6.1
When specified by the Design Engineer, elbow type separable
connector terminations may be used to terminate 15 kV and 35 kV
rated cables to compartment type padmounted transformer or
padmounted switching cubicles.
3.6.2
All elbow terminations shall be rated 200 amperes for load break
service and 600 amperes for no-load break services.
3.6.3
The elbow terminations shall be provided with a capacitive test point.
3.6.4
The application of elbow terminations shall be performed in strict
accordance with the manufacturer's installation procedures.
3.6.5
All elbows shall comply with IEEE Standard No. 386.
TESP10404R0/YM
Date of Approval: December 16, 2006
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