August 2015
QUMBU SUBSTATION
SCOPE FOR
132kV FEEDER BAYS
Scope of Works
1.1
LOCATION OF SITE
Qumbu substation is an existing 132/22kV substation located approximately 60km from Umthatha,
G.P.S Long 28° 53' 9.3" Lat-31° 10' 46.4"
1.2
PHASING OF THE PROJECT
The aim of the project is to reposition the existing Ugie 132kV feeder, construct a double busbar and
add a new Amacwera 132kV feeder. A more integrated outage plan must be developed taking into
account if the use of live team where possible in consultation with all construction parties as well as
taking the network constraints into account.
1.3
YARD WORKS
1.3.1
BENCH MARK
Create a benchmark on site in the position suited to the construction of the 132kV feeder bay.
ELECTRICAL PHASING
Electrical phasing of Feeders, Busbar 2 &3 is to be done as per D-EC-855-11-01A
132KV BUSBAR 1
The existing 132kV tubular busbar is to be modified as shown in D-EC-855-11-07 rev 6
132KV BUSBAR 2 & 3
Establish a double busbar using a tubular support busbar construction as shown on D-EC-855-1107&08 rev 6.
132KV BUSBAR 2 & 3 VOLTAGE TRANSFORMER
Install a voltage transformer on red phase per busbar on the 132kV busbar as detailed on D-EC-855-1107 rev 6.
UGIE 1 132KV FEEDER
The existing Ugie 132kV feeder bay is to be repositioned as shown in D-EC-855-11-07 rev 6. All
equipment in this bay is new. The current transformers will be re-used in a new position with new
supports as indicated, the jumpers and clamps are to be installed and connected as shown on D-EC-85511-08 rev 6.
AMACWERA 1 132KV FEEDER
Establish a 132kV feeder bay as detailed on D-EC-885-11-07 rev 6. After the line termination has been
completed to the beam, the jumpers can be installed and connected as shown D-EC-855-11-08 rev 6.
KERBING
Install stone kerbing as indicated on D-EC-855-11-11 rev 6. Allow 10mm gaps (ungrouted) every 3m
between kerbing for water seepage.
LIGHTNING PROTECTION
Install 1 x 21m lighting masts and for the direction of floodlights is indicated on D-EC-855-11- 07 rev
6. Each mast must be fitted with a surge arrestor which is not indicated on the wiring diagram. Install
earth wire between the earth wire peaks on the columns as well as lightning spikes as indicated on DEC-855-11-06 & 07 rev 6.
1.3.2
1.3.3
1.3.4
1.3.5
1.3.6
1.3.7
1.3.8
1.3.9
1.3.10 EARTHING
All steelwork is to be earthed to the foundation HD bolts inclusive of the columns. The 132kV Voltage
Transformers, 132kV Current Transformers to earthed in accordance with the Project Specification and
Earthing Standard. Install portable earthing balls on the equipment steelwork supports as detailed on DEC-855-11-04 rev 6 and positions are to be confirmed by the Technical Services Officer for Qumbu
Technical Services Centre. The new section of the main earthmat is to be installed at a depth and
position indicated on D-EC-855-11-04 rev 6.
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1.3.11 YARD STONING
Stock pile yard stone on the area where work is to be carried out and re-spread when all work has been
done as indicated on D-EC-855-11-11 rev 6 (Project Specifications). Supply and install yard stone in
the new section when all work has been done as indicated on D-EC-855-11-11 rev 6 (Project
Specification).
1.3.12 TRENCHING
Extend the existing trenches by installing new 750mm wide trenches with covers as shown on D-EC855-11-11 rev 6.
1.3.13 FENCING
The existing palisade fence is to be modified with the installation of new palisade security fencing as
shown in D-EC-885-11-11 rev 6.
1.3.14 WEED KILLER
Spray weed killer in the substation on all the stoned and paved areas once all the stoning and paving has
been completed (Project Specification).
1.3.15 LABELS
Install equipment labels, busbar labels and phasing discs as detailed on D-EC-855-11-01A. The
positions of the phasing discs and label brackets are indicated on D-EC-855-11-06 rev 6. Install fence
and gate labels (Project Specification).
1.3.16 JB BRACKETS
The Isolator JB bracket is to be mounted on the busbar isolator (IS4)
1.3.17 LV CONTROL CABLES
Install the secondary cables where required. Note; The cable block diagram will be issued once the
contract is awarded.
1.3.18 BREAKER STAINLESS STEEL BOLTS
The stainless steel bolts and washer for the 132kV breakers are required only if ABB does not supply
1.3.19 DECOMMISSION
Disconnect and remove existing 132kV Ugie feeder bay with its foundations. Disconnect and remove
all jumpers in the existing 132kV Ugie feeder bay. Dismantle and remove all equipment for re-use in
the new position of the 132kV Ugie. Rehabilitate the soil in the area where the existing feeder was.
Dismantle and remove the existing internal fence as shown in D-EC-855-11-11 rev 6.
1.3.20 CONSTRUCTION RISK
Risk
Mitigation
Access:
Substation is restricted area and public and
visitors should not be allowed to enter
without approval.
Insects:
Existing cabinets are often inhabited by
bees, wasps and hornets.
Gates:
The substation is a restricted area and gates
must be closed at all times.
Oil Spill:
Some equipment is oil filled and extreme
care must be taken when handling the same
since the risk of an oil spill is high
Snake:
Since the construction will take place during
the summer the risk of encountering snakes
is high.
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Induction training of both staff and visitors
required.
Induction training of both staff and visitors
required.
Observe status of gates at all times.
Induction training of staff to include oil spill risk
and action if a spill should occur.
Staff should be educated regarding the types of
local snakes that may be encountered.
Porcelain:
The equipment has in most instances
porcelain insulators and extreme care must
be taken when handling the equipment not
to chip and/or break the insulators. Chipped
insulators could render equipment unfit for
use or injury.
Close proximity:
Should works be undertaken in an
operational yard care must be taken when
handling/erecting conductive components
such as steelwork.
Staff must be made aware of the risk and the
correct lifting equipment must be used when
lifting the equipment.
Induction training of staff to include risk
associated with working in close proximity.
1.3.21 GENERAL
The contractor to whom the tender is awarded must make his own copies of the drawings to use during
construction. For ease of reading, references has been made throughout this document to relevant
project drawings , BOQ & specifications, it however remains the contractors responsibility to ensure the
he/she complies to all specifications and standards relating to the Project.
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