3.5 electrical design criteria-well platform

8/12/2019 3.5 Electrical Design Criteria-well Platform

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TABLE OF CONTENTS

Sr. No. 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


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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


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3.5.1 INTRODUCTION

3.5.1.1 General

The document specifies the minimum technical requirement for electrical systemassociated 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 have meaning assigned to them

except where the context specifies otherwise.

DC Direct CurrentAPI 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.

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.

3.5.2.2 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 Definition5006 General Specification For Site Condition And

Climate


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2005 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 InformationAll 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 DESIGN

3.5.4.1 Electrical Loads

3.5.4.1.1 Definitions.

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 load-

which 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 thelargest 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 DropThe 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.

Switch Board/Distribution 1%

Boards/ Lighting power panel

Lighting Points 2%

DC system 3%

3. 5.4.3 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 ProtectionAs the method of construction shall incorporate bonded metal structure, no specific

lightning protection shall be needed.

3.5.4.5 Plant LayoutElectric room (Switch gear room) shall be located in safe, non-hazardous and well-

ventilated area.

a) All equipment such as solar power controllers, lighting, DC power 25/24/12volts & 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 locatedin 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 bemanufactured 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-RP-

500B.

The hazardous area classification drawing shall be the basis of classification ofelectrical 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 Following loads shall be classified as continuous loads requiring electrical powercontinuously 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

3.5.5.3.2 Following lighting loads shall be considered. Lighting load shall be considered forthree hours every day.

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

ii) 2 Nos. 24 V DC, 60W lighting fixtures with two-pole on/off switch inBattery 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 25V + 4%, -0%

System (Negative earthed)


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ii) Electrical system for Data Logger, 24V + 5%, -0%

strobe light & lighting system (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

3.5.5.4.2 Permissible Voltage DropMaximum 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 Wiring Methodi) 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 shallconfirm 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.

3.5.5.5 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 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 manufacturers 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 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 the requirement of ONGC

functional specification number FS 4001.

3.5.5.7.2 Cathodic Protection for submarine Pipelines.


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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 PanelsSmall 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 andunused, 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.

attery 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 battery

and obstruction light.

Ear thing cable and conductor.

Cable gland and junction box.

MCTs frames.


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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 companys established identification system.

3.5.10 Electrical Equipment Inspection & Testing Philosophy:

The Contractors 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 to carry

out all necessary tests for the electrical equipments.

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 Companys

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.

3.5 electrical design criteria-well platform

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