VOL No II REV No. 2 Section 3.5 OFFSHORE

OFFSHORE
DESIGN
SECTION
MUMBAI
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ELECTRICAL
DESIGN CRITERIA

VOL No II
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TYPICAL WELL PLATFORM

Section 3.5
Page No: OF 27

SECTION 3.5

ELECTRICAL


DESIGN CRITERIA

27
PREPARED
BY

REVIEWED
BY

ISSUED AS

APPROVED BY

TOTAL
PAGE

2
DATE

REV NO


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Page No: OF 27

TABLE OF CONTENTS
Sr. No.


Section 3.5

Description

3.5.1

Introduction

3.5.1.1

General

3.5.1.2

Definition and Acronym

3.5.2

Codes And Standards


3.5.2.1

Codes, Standards and Regulations

3.5.2.2

Project General Specification

3.5.3

General Requirement

3.5.3.1

Safety

3.5.3.1.1

General


3.5.3.2

Material and Workmanship and suitability

3.5.3.3

Design Life

3.5.3.4

Units and Information

3.5.4

Electrical System Design

3.5.4.1

Electrical Loads


3.5.4.1.1

Definition

3.5.4.1.2

Loads Assessment

3.5.4.2

Calculation Methods

3.5.4.2.1

Cable Sizing

3.5.4.2.2

Voltage Drop


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3.5.4.3

Ear thing


3.5.4.4

Lighting Protection

3.5.4.5

Plant Lay out

3.5.5

Specification Requirements For Equipments and Cables

3.5.5.1

General

3.5.5.1.1

Environment


3.5.5.1.2

Corrosion

3.5.5.1.3

Enclosure Protection

3.5.5.1.4

Hazardous Area Requirements

3.5.5.1.4.1

Standards

3.5.5.1.4.2

Certification


3.5.5.1.4.3

Misc. Requirement

3.5.5.2

Junction Boxes

3.5.5.2.1

Junction Boxes- Direct Cable Entry Via Gland

3.5.5.3

Solar Power System

3.5.5.4

Electrical design system


3.5.5.4.1

System voltage/utilization voltage

3.5.5.4.2

Permissible voltage drop

3.5.5.4.3

Wiring method

3.5.5.5

Navigational Aids System .

3.5.5.6

Cables

Section 3.5
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VOL No II
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TYPICAL WELL PLATFORM

3.5.5.6.1

General

3.5.5.6.2

Earth Conductor

3.5.5.6.3

Cable Support System

3.5.5.6.3.1

Cable Tray and Ladders

3.5.5.6.3.2

Cable Glands and Transit Frames

3.5.5.7

Cathodic Protection

3.5.5.7.1

Cathodic Protection for Offshore structures

3.5.5.7.2

Cathodic Protection for Submarine Pipelines

3.5.5.8

Small Light and Power Distribution Boards

3.5.6

Electrical Equipment Selection Philosophy

3.5.7

Electrical Equipment Calculations

3.5.8

Review and Approval

3.5.9

Tagging and name Plate

3.5.10

Inspection and Testing Philosophy

3.5.11

Documentation

3.5.11.1

Equipment Documentation

3.5.11.2

Electrical Equipment Index

3.5.11.3

Electrical Equipment Data Sheet

Section 3.5
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3.5.1

INTRODUCTION

3.5.1.1

General

VOL No II

Section 3.5
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The document specifies the minimum technical requirement for electrical system
associated with this bid package. The specified design criteria cover technical
requirements, calculation methods, functional requirements, margins and any
other minimum requirements.

3.5.1.2

Definition and Acronyms.
The following words and expressions shall
except where the context specifies otherwise.

have meaning assigned to them

DC

Direct Current

API

American Petroleum Institute

FRP

Fiber Glass Reinforced Plastic

LV

Low Voltage

IEC

International Electrotechnical Commission

IPXX

Ingress Protection

NEMA

National Electrical Manufacturers Association

MCB

Miniature Circuit Breaker

MCCB

Moulded Case Circuit Breaker

SS

Stainless Steel

TEFC

Totally Enclosed Fan Cooled

3.5.2

CODES & STANDARDS

3.5.2.1

Codes and Standards and regulations

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The specification of design requirements, materials and system performance shall
be based upon the requirements of the latest version of all applicable international
Standards , Codes , regulation and code of practice outlined below.

3.5.2.2

IEC

International Electro Technical Commission

NEMA

National Electrical Manufactures Association(USA)

ASTM

American Society for Testing and Material(USA)

NFPA

National Fire Protection Agency(USA)

IALA

International Association of Light house Authority

BSI

British Standards Institution

ANSI

American National Standards Institute

API

American Petroleum Institute(USA)

NEC

National Electric Code(USA)

SOLAS

Convention on safety of life at sea.

NESC

National Electric Safety Code(USA)

BIS

Bureau of Indian Standards

DNV

Dets Norske Veritas

NACE

National Association of Corrosion Engineer( USA)

MARPOL

Marine Pollution Act

CENELEC

European Standards published by CENELEC.

Project General Specification:
The contractor shall refer the following Project Specification in association with
the standards and codes mentioned.
Specification Number

Description

1050

General Specification For Definition

5006

General Specification For Site Condition And
Climate

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Section 3.5
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General Specification For Protective Painting

3.5.3

GENERAL REQUIREMENT

3.5.3.1

Safety

3.5.3.1.1

General
The electrical system shall employ safety margins to ensure that plant is safe under
all operating conditions, including those associated with the start up and shut down
of equipment and through out intervening shut down periods. The emphasis in
equipment specification will be on operability, prevention of accident/ fault and
functionality for the design life.
All insulating materials specified for the equipment elsewhere in document shall be
non toxic.
All cable penetrations through firewalls, blast walls, through switchgear room
walls and between safe and hazardous area shall be sealed using multi cable
transits to maintain the integrity of system and prevent gas migration. The sealed
transit shall ensure that the fire integrity of the wall is maintained.

3.5.3.2

Materials Workmanship & Suitability
All work shall be of the highest quality craftsmanship and shall conform to the
applicable standards and best applicable engineering practices in order to achieve
a neat, safe, substantial and functional installation.
All the materials utilized in the construction of electrical equipment shall be as
per the latest standards and specification. The materials and equipment used
shall be new, unused and of current manufacture. Should any material prove
unsatisfactory it will be rejected notwithstanding any previous satisfactory
examination or test of similar material or of completed cables and equipment.

3.5.3.3

Design Life.

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The electrical system shall be designed for
specified operating life of
platform. Therefore equipment shall be specified by contractor for the design life
considering maintenance requirement wherever applicable.

3.5.3.4

Units and Information
All quantities and dimensions shall be expressed in metric units. All information,
manuals , certificate data and inscriptions shall be in English language.

3.5.4

ELECTRICAL SYSTEM

3.5.4.1

Electrical Loads

3.5.4.1.1

Definitions.

DESIGN

The following definition will be applied in the preparation of load schedule.

Items

Definitions

Nominal power

Name plate rating of motors or load absorbed by non
motor load.

Efficiency(%)

It is the output divided by input. For motors it shall be
as per vendor data and complying with the IEC
standard.

Load classifications.

Electrical load are to be classified as Normal,
Emergency and Essential .Normal – Loads in service
for full process/production application. Essential- The
load required for life support and occupancy purpose.
Emergency - Necessary for personnel safety / safe
shut down and abandonment purpose.
Utilization Category
Loads shall be divided into
three classes according to use. Continuous loadwhich draw power at continuous rate .Intermittent

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load-which draw power as per duty cycle for small
time. Stand by
load- which are connected with
power supply and ready to act when required.
3.5.4.1.2

Load Assessment.
An Electrical load shall be developed by the contractor based on the guide line
described in the table. The maximum load developed shall be used to specify
maximum power requirement, feeder cable sizing, switch gear sizing and MCC
general arrangement etc.
The equipment utilization category and load assessment is tabulated as below.
Sr. No.

Utilization category

Load Assessment

1

Continuously operating equipment

100% of operating load.

2

Intermittently operating equipment

50% of the total
intermittent load or the
largest intermittent load
which ever is greater.

3

Standby - equipment

10% of total ‘ standby’
load or the largest
‘standby by’ load, whichever
is greater.

4

Margin for future load growth

10% of sum of load at
Sr. No. 1,2&3

5

Total load

It shall be Sum of load
at 1,2,3, and 4.

3.5.4.2

Calculation Methods

3.5.4.2.1

Cable Sizing
During detailed engineering all power cables shall be identified and sized
according to the requirement of Indian and International standards. All the cables
for AC/DC loads shall be sized individually satisfying all the following criteria:

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Current carrying capacity.
Voltage drop steady state.
Voltage drop limit during starting of motor.
Shortcircuit temp rise.
Where ever possible main power cables should be run with sufficient spacing in
cable tray to minimize de rating due to grouping.
For incoming feeders, branch circuits and feeders for motors and lighting power ,
conductor current rating shall be established on the basis of 125% of design load
current at an ambient temperature of 40 degree centigrade and de-rated for
grouping and method of installation. The voltage grade of LV power and control
cables shall be 1100 volt AC.
3.5.4.2.2

Voltage Drop
The system nominal utilization voltage level shall be 24 /12 volt DC.
The maximum allowable voltage drop in any feeder under steady
state conditions shall be maintained as below.

3. 5.4.3

Switch Board/Distribution
Boards/ Lighting power panel

1%

Lighting Points

2%

DC system

3%

Earthing
Plant earthing shall be as per API- RP-14F. All electrical equipment shall be
earthed via earthing conductor within power cable and where mechanical
equipment contains electrical apparatus earth bonding shall be required.
The minimum size of earth bonding conductors on local control station enclosures
shall be 16mm2.The minimum size of earth conductors for electrical panels shall be
16 mm2.

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Vessels, tanks, and mechanical packages not directly welded to the structure shall
be bonded to a structural earth pad or boss using at least two independent 70 mm2
conductors.
Metallic cable trays shall be suitably earthed.
Items such as pipes and duct work that have insulating material( i. e. gasket )
between connected sections shall be made electrically continuous by bonding with
a 6 mm2 earthing cable or equivalent earthing strip.
All electrical panels shall be provided with a tinned copper earth bar.
3.5.4.4

Lightning Protection
As the method of construction shall incorporate bonded metal structure, no specific
lightning protection shall be needed.

3.5.4.5

Plant Layout
Electric room (Switch gear room) shall be located in safe, non-hazardous and wellventilated area.
a) All equipment such as solar power controllers, lighting, DC power 25/24/12
volts & miscellaneous distribution boards Gas detection panels etc shall be
located in closed electrical room and shall be designed considering inadequate
ventilation in the room .
b) All batteries shall be located in closed battery room .The room will be located
in safe area . Batteries shall be designed considering inadequate ventilation in
the room.
All electrical equipments shall be installed in a neat workman like manner for
ease of operation and maintenance and from safety viewpoint.
The Contractor shall prepare single line and schematic wiring diagram of all type
of DC Power distribution panel and submit to company for approval.
The contractor shall calculate number and size of anode, prepare anode distribution
drawing, hazardous area classification diagram, switch gear room layout on deck,
electrical equipment and battery enclosure layout in switchgear room, earthling
layout diagram, cable and tray layout,, cable tray sizing , MCT sizing, complete

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cable schedule, navigational lantern layout, layout with junction box, and solar
panel layout and submit to company for approval.
Any other drawings/documents required to make the electrical system complete
and operational but not mentioned here shall be developed by contractor.
The Contractor shall install electrical equipments only in approved locations, with
due consideration of the following:
• Positioning of equipment (out door and indoor) shall not constitute a safety
hazard.
• Visibility and accessibility for both maintenance and operations purpose.
• Light fixtures shall be fitted so that they can be serviced and removed by a
single person.
• Cables and cable ladder shall not be fixed to gratings or handrails.
• Stainless Steel tags are to be provided for Cable at each bend and at interval of
6 meter.
• Cables shall be properly tied in FRP cable trays at 600/800 mm interval.
• Cable tray height must be minimum 2.5 meters for safety and convenience.
For convenience and ease in maintenance as well as operation, the minimum
clearance between electrical equipments or between other items and electrical
equipment shall be as tabulated below:
Distance

Item description

1200 mm

Frequent access (primary escape rout)

1000mm

infrequent access (secondary escape route)

1500mm

Minimum access between operating faces of floor mounted
Switch- gear (MCC) panel.

1000mm

Rear clearance of panel requiring maintenance from rear.

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150 mm

Rear clearance for panels having only front access.

1000mm

Front clearance for wall mounting equipment

1000mm

Transformer front clearance.

800mm

Headroom clearance for MCC Panel, DC power panel etc.

3.5.5

SPECIFICATION REQUIREMENTS FOR EQUIPMENTS AND CABLES.

3.5.5.1

General

3.5.5.1.1

Environment:
Electrical equipment, installation material, wiring and cabling etc. will be suitable
for the overall climatic condition, their position within the installation and local
environment. For environment, climatic and operating condition reference may be
made to the Project General Operating Conditions Specification number5006.

3.5.5.1.2

Corrosion
The indoor equipments enclosure like LV switch board, small light and DC
power panels, transformer etc. shall have anti corrosion protective coating as per
requirement of “ Protective Coating General Specification number 2005”. The hard
wares shall be high tensile MS duly cadmium plated.
For external locations corrosion resistant materials will be specified for electrical
equipments.
As a minimum material/equipment requirement shall be as follows.
Cable ladders and trays shall be fiberglass Reinforced Plastic and UV
protected.
Associated accessories shall be SS316.

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Explosion proof junction boxes, light fitting, control stations etc shall be
manufactured of copper free aluminum with an epoxy finish.
Hardwares shall be of stainless steel.
Cable glands shall be nickel plated brass double compression type or
equivalent.
3.5.5.1.3

Enclosure Protection.
The degree of protection against dust and water ingress , necessary for individual
electrical items shall be determined by the equipment duty, its environment, its
location and the hazardous area classification. The equipment located outside or
subject to deluge from fire water system shall be of weather proof construction
and protected against the most adverse conditions that are anticipated. These
enclosures are to be classified to IP56 as a minimum degree of protection,
increased as necessary where the location/situation demands.
Indoor equipments like MCC, DC power distribution panels, etc. will be, as a
minimum, of IP51 protection class.

3.5.5.1.4

Hazardous area Requirements.

3.5.5.1.4.1 Standards
The hazardous area classification shall be carried out in accordance with API-RP500B.
The hazardous area classification drawing shall be the basis of classification of
electrical equipment for various location.
3.5.5.1.4.2 Certification
All offered items and equipments or those of similar designs manufactured by the
same supplier:
shall have been type tested by an authority approved by the Company.
shall have been in continuous satisfactory service on offshore for a minimum
period of two years.

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Shall be having current certification/approval/listing by UL or FM or by an
agency approved by company.
3.5.5.1.4.3 Miscellaneous Requirement
Outdoor equipment and required to be powered during an emergency shall be
certified for class-I division-I regardless of their location. All other electrical
equipment shall be classified according to the location.
However, all the outdoor electrical equipment on the platform handling oil and gas
shall, at-least, be suitable for Class I, Division II, gas group D area unless
otherwise specified.
The equipments/items installed in battery room shall be suitable for class I Division
I, Gas group B area.
3.5.5.2

Junction Boxes.

3.5.5.2.1

Junction Boxes - Cable Entry Via Glands.
Junction boxes for use in outdoors shall be certified for use in Class I Division I
and T3 hazardous area and fabricated from the copper free aluminum. It shall be
Epoxy coated and have marine grade paint finish.
The terminals shall be pressure or clamp type as demanded by load and they shall
be anti vibration and anti loosening type.
The junction box shall be as per the requirements of light fitting and Junction box
functional specification number FS 4006.

3.5.5.3

Solar Power System
The solar power system shall be designed as per functional specification FS 4007.
The solar power system shall be self sustained type. The Batteries associated with
electric solar power system shall be chargeable type. The system shall be sized for
seven (7) ‘NO SUN’ days and at the end of the 7 ‘NO SUN’ days the batteries
shall be recharged while also feeding the load. Battery capacities shall be designed
accordingly.

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Batteries shall be designed to take care of continuous loads as well as lighting
load.
3.5.5.3.1

3.5.5.3.2

Following loads shall be classified as continuous loads requiring electrical power
continuously round the year. Electrical power system backed up by batteries shall
be provided for feeding the “Continuous Loads”. Independent electrical power
system shall be provided for each of the following:
-

Telemetry System

-

Data Logger and strobe light

-.

Navigational Aid System

-

Gas Detection system

Following lighting loads shall be considered. Lighting load shall be considered for
three hours every day.
i)

2 Nos. 24 V DC, 60W lighting fixture with two pole on/off switch in
switchgear/electric room.

ii)

2 Nos. 24 V DC, 60W lighting fixtures with two-pole on/off switch in
Battery room.

Sizing/Laying of cable installation of distribution board shall be under the scope
of Contractor. The one of each type feeder shall be provided for future load
provision.
3.5.5.3.3

Initial charging of all the batteries shall be carried out by Contractor. All
necessary equipments for initial charging shall be arranged by the Contractor.

3.5.5.4

Electrical System Design

3.5.5.4.1

System Voltage/Utilization Voltage
Power system shall be designed for the following system as under and Utilization
Voltage for various loads shall be as follows:
i)

Electrical System for Telemetry
System

25V + 4%, -0%
(Negative earthed)

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3.5.5.4.2

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ii)

Electrical system for Data Logger,
strobe light & lighting system

24V + 5%, -0%
(unearthed or negative
earthed as required)

iii)

Electrical System for Navigation Aid

Compatible with utilization
voltage of lanterns.

iv)

Electrical System for G.D.System

24V + 5%, -0%
(unearthed or negative
earthed as required)

v)

Lighting

24V DC

Permissible Voltage Drop
Maximum voltage drop in any circuit shall not be more than 2 %. It shall be
ensured that end voltages at the utilization points are within the permissible limits
of equipment requirement.

3.5.5.4.3

3.5.5.5

Wiring Method
i)

The preferred method of interconnection of the various type of electrical
device is by multicore cables.
All cables shall be flame retardant low smoke (FRLS) type except between
solar panel, controller, Battery Bank, DCDB and gas detectors which shall
have fire rated insulation (750 degree centigrade for 3 hours) cables shall
confirm to IEC 331 and 332.

ii)

Junction boxes and associated accessories with DC lighting shall be
flameproof type.
The multicable transits (MCTs) shall be provided where cables and
pneumatic tubes pass through a wall or floor/deck.

NAVIGATIONAL AIDS SYSTEM
The navigational aids lantern, solar panels, solar power controller and battery
shall be provided in accordance with the Navigational Aids and Solar Power Panel

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specification number FS4003 & FS 4007 respectively. The battery bank shall be
sized for back up supply for case of 7 “ NO –SUN” days.
3.5.5.6

CABLES

3.5.5.6.1 General
All cables shall have flame retardant characteristics to IEC 60332-3 category A.
The solar panel interconnection and wiring cables, navigational aids lantern
cable shall beflame retardent low smoke type(FRLS).
In line cable joints via cast resin kit or other type shall not be permitted.
All cables shall be of copper conductor.
Minimum wire size for power and lighting shall be 4mm2.
Minimum wire size for control shall be 2.5 mm2.
Special care shall be taken to the routing and separation of cables to minimize the
effect of fire on emergency and essential supplies and production operations.
All cables shall be identified with SS316 Tags.
In addition the minimum distance between power/control wiring and electronic
signal wiring on prolonged cable route will be as follows:
Power /control cable

Minimum distance from electronic/ signal cable

Up to 125 volt

150mm

Up to 300v

150mm

Up to 1000v

300mm

Above 1000v

450mm

The cable shall be as per detailed requirements of Power & Control Cable
Functional Specification number FS 4011.

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3.5.5.6.2

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Earth Conductor
Earth cable shall be 6 mm2, 16 mm2, 70 mm2 or 240 mm2 stranded copper
conductor with PVC insulated and green / yellow insulation sheath.
Earth conductor requirement shall be as per cable specification number FS 4011.

3.5.5.6.3 Cable support System
The cable system shall comprise cable installed on cable tray or ladder with 25%
spare capacity for future extension.
Intrinsically safe circuit cables shall be in separate tray.
Conduit systems shall not be used.
Single core AC cables shall be laid in trefoil group.
Cable straps or ties shall be SS316.
3.5.5.6.3.1 Cable tray /Ladder
Two primary cable tray /ladder system shall be installed.
Low voltage power and control cable.
Instrumentation, control and ESD.
Cable ladders /trays shall be manufactured from FRP and UV protected ( see
section 3.5.5.1.2).
Cable ladders shall be fitted with removable, ventilated covers where there is
exposure to chemical spillage, falling object or direct sunlight. The covers and
tray support will be suitable to withstand cyclone/monsoon conditions.
Cable tray shall be installed in accordance with manufacturer’s recommendations
and specifically supported at each elbow. The overhead cable trays shall be
installed a minimum of 2.5 meter above deck.
The cable tray and ladder shall be as per the requirements of FRP tray functional
specification number FS4005.

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3.5.5.6.3.2

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Cable Glands and Transit Frames.
Suitable size double compression type glands shall be supplied for all cables.
For entries into Ex(d) enclosures, barrier type ( or compound filled) gland shall
be provided. All cable glands and adaptors will be made of nickel-plated brass
and shall be fitted with soft sealing nylon washer. Fiber washers shall not be
used.
Lock nuts shall be used for entry into sheet steel boxes enclosures.
All cable glands shall be type tested and certified for use in hazardous area
equipment.
Cable transit frames shall be fitted where cables pass through:


decks and walls to open air.



Fire/blast walls.



From safe to hazardous area.

Such cable transit frames shall include 25% spare capacity for future use.
Cable transit frames shall be supplied with a test certificate from an independent
test authority to confirm a fire and blast rating adequate for deck or wall in
which it is installed.

3.5.5.7

Cathodic Protection

3.5.5.7.1

Cathodic Protection for Offshore Structures.
The electrical requirement of cathodic protection system are to be read in
conjunction with description of work and specification for jacket, PLEM etc.
given elsewhere in bid package. It shall be without monitoring. The design life of
CP system shall be the specified life of facilities i.e. Jacket, PLEM, SPM etc.
The CP system
shall be in accordance with
functional specification number FS 4001.

3.5.5.7.2

Cathodic Protection for submarine Pipelines.

the requirement of ONGC

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The electrical requirements are to be read in conjunction with the description of
work and specification for submarine pipelines and risers given else where in bid
package. The Design life of CP system shall be the specified life of platform.
The CP system for rigid pipeline and flexible pipeline shall in accordance with the
requirement of ONGC functional specification number FS 4002.
3.5.5.8

Small Light and Power Panels
Small light and AC/DC power distribution board shall be of heavy duty sheet steel
enclosure construction for installation in non hazardous area ( inside electric room).
The board shall be constructed in accordance with Indian and international
standards.
Each board shall be equipped with an incoming isolator ( MCCB/MCB), chassis
mounted bus bar system and miniature circuit breaker or MCCB for power
distribution feeder. The spare feeder shall be 20%.
The ingress protection rating shall be IP51. An earth bus shall be provided with
each board and shall be fitted with suitable ring type lugs for all outgoing circuits.
In general any circuit feeding equipment located in hazardous area shall utilize
circuit breakers that break all poles. The board /panel shall be as per the
requirements of panel board functional specification number FS4004.

3.5.6

ELECTRICAL EQUIPMENT MATERIAL SELECTION PHILOSOPHY:
All materials and equipments furnished shall be as per relevant standards, new and
unused, of current manufacture and of the highest grade and quality available for
the required service, and free of defects and as per international standards. The
equipment shall be protected from construction damage and damage in
transportation. and damage due to sandblasting and painting.
Materials shall be selected with regard to the following :


Functional specifications and design criteria for each electrical items of this
project.



All applicable standards and codes.

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Reliable & trouble free performance.



Safety of personnel, plant and minimal fire risk.



General operating conditions.



Compatibility with area classification of the place of installation.



Suitability for the corrosive effects of the saline and humid marine
atmosphere.



Galvanic compatibility between dissimilar materials, with isolating bushes,
plates, used where necessary to prevent corrosion due to galvanic action.

3.5.7

ELECTRICAL EQUIPMENT CALCULATIONS:
The Contractor shall provide vetted calculations for electrical equipments’ size,
rating, power, capacity, quantity etc of the electrical equipments with reference to
relevant codes and functional specification. The electrical equipments and
materials shall include but not limited to the following.


sacrificial anode for cathodic protection system of offshore structures and
submarine pipelines.



Βattery Bank



LV switch gears DC power panels.



Power and control cable.



Lighting fixtures and accessories.



Cable tray, Ladder and accessories.



solar panel along with accessories, solar power controller, Nav. Aid
and obstruction light.



Ear thing cable and conductor.



Cable gland and junction box.



MCTs frames.

battery

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Any other equipment and accessories to make the electrical installation
complete in all respect.

These shall form part of the relevant Purchase Specification to be submitted during
Detailed Engineering. Vetting is to be done by the company or an agency approved
by the company.
3.5.8

REVIEW AND APPROVAL:
All purchase specifications along with list of deviations, calculation sheets, offers
of the vendor and all relevant correspondence shall be furnished for Company’s
approval.
Contractor shall not place the order without obtaining prior approval from the
company.
Contractor shall prepare and furnish the list of all drawings / documents as enlisted
in the bid document for Company’s review. The category of drawings / documents
(i.e. whether to be reviewed / approved by the Company) shall be decided after
award of Contract.
All vendors drawing shall be submitted for company’s review after the contractor’s
engineering consultant approves them.

3.5.9

TAGGING AND NAME PLATES:
All equipment (Motors, push buttons, motor control centers, push button stations,
junction boxes, etc.) Shall have SS tag or nameplate of a permanent type with
identification number and service description.
The tag number that pertains to an electrical equipment shall appear on all
drawings and documents approved by company.
Nameplates and identification tags shall be provided to properly identify each piece
of electrical equipment.
All panel electrical equipment nameplates shall be constructed of white laminated
plastic plates with black engraved lettering and securely fastened with 316 SS
screws.

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All front panel mounted equipment shall also be identified with a metal or plastic
nameplate attached to the rear of the device, and easily visible via the rear access
doors.
All wiring, power and control cables, junction boxes, terminal blocks and auxiliary
equipment shall be suitably identified as per applicable codes and practices. Plastic
adhesive tapes shall not be used for identification. All wiring shall be tagged with
slip on or clip-on wire marker at both ends, with the wire number specified on the
drawing as per company’s established identification system.
3.5.10

Electrical Equipment Inspection & Testing Philosophy:
The Contractor’s quality plan shall include a comprehensive fully documented
inspection and testing plan specific to the project and it shall be submitted to
company for review and approval.
The Contractor shall provide suitable workshop, equipment and facilities
out all necessary tests for the electrical equipments.

to carry

The Company reserves the right to reject any or all test work if the same is not in
line with requirement of relevant specification.
The Contractor shall, in the presence of the Company Representative, verify by
inspection and testing that, all electrical equipments in field and control room
including local and remote/central control panels is complete and operable. All
testing shall be subject to approval of the Company.
All Electrical equipments need to be checked and certified prior to shipment by
company rep. and/ or company approved certifying agency.
In addition to yard testing of loop checking and setting for safety devices like
overload relays and Instantaneous trip rely, simulation testing of all interlock and
shutdown systems etc, also shall be carried out at offshore.
Verification shall be carried out that grounding points are installed properly.
Insulation test shall be carried out on all cabling by using a meggar of 500 volt
DC. It should not be less than 10 M ohm for LT system.
Correct connections of all electric equipment shall be checked.

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All testing
and pre-commissioning shall be done by the Contractor. The
Contractor shall also provide assistance as required to assist the Company’s
commissioning activities.
The Contractor shall submit the results of all above tests to the company and if
required by the Company, the contractor shall provide reasonable evidence of the
satisfactory condition of test equipments.
3.5.11

DOCUMENTATION:
The contractor shall provide hard copies plus electronic copies on CD for all the
documents.

3.5. 11.1

Equipment Documentation:
The Contractor shall provide the following documents as a minimum:


Engineering, Design and calculation books.



Operating philosophy of the system and proposed maintenance schedule of
all major components, for the design life of the system including
replacement requirements of parts.




Specifications, test certificates and data sheets for all items.
Deviation schedule for items if any.



Anode location drawings.



Single line diagram, schematic diagram and functional wiring diagram of LV
Switch gear and all DC panels.



Bill of materials.



Cable and tray routing drawings and cable schedule.



Ear thing layout.



Lighting fixtures, solar panel and obstruction light layout drawings.

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Interconnection and hook up drawings.



MCT frame drawing.



Equipment layout drawing in electric room and as built drawings.

.

Battery /Battery rack layout

Minimum 3 (three) sets of Dossier shall be provided to the Company.
The contractor shall be responsible for the authenticity of the drawings & data
provided by the vendor as well as sub-vendor(s).
Each vendor data items requested above must be identified by the Purchase Order
number and equipment tag number located on the cover sheet or first page of said
item and in the case of engineering drawings on each and every drawing.
Any additional data/drawings required, as a result of issuing supplements to a
purchase order or during detailed engineering, shall be furnished by Vendor and
handled in the same manner as the original order.
All drawings and literatures shall be in English language and in the Metric
Measurement System.

The reproducible drawings, 279mm X 432mm (11" x 17") size and full size are to
be of such quality that clear legible prints can be made.

3.5.11.2

Electrical Equipment Index:
The contractor shall provide an electrical equipment Index.
The index shall include the information listed below:


Electrical Tag Number.



Service Description.



Rating/type.

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Electrical drawing (single line, schematic and wiring Drawing) Number.



Data Sheet Number

The electrical index shall form the basis for documenting all electrical drawing
and shall be listed in alphanumeric order of electrical tag number and shall
contain all relevant information for each electrical item.. The index shall be based
on Microsoft Access.
3.5.11.3

Electrical equipment Data Sheet:
A duly filled data sheet shall be provided by contractor for every item of
electrical equipment, including those which are part of packaged plant. The data
sheet shall include but not limited to the following.


Manufacturer name.



Model/type



Standard and code reference



Electrical parameter Details



Construction Materials details



Performance details



Mechanical/ physical Details



General arrangement drawing showing electrical equipment and details of
interface.



Test certificate



Hazardous area classification and certificate details (type of
protection, certifying authority.)

When a number of items are identical in their requirements, these can be covered
by a single specification sheet, provided all tag numbers are clearly listed.
The Contractor shall submit his proposed data sheet for Company approval.
Data sheets shall be generated using Microsoft Excel.