specification for electrical equipment to be...

VISAKH MARKETING INSTALLATION

RESITEMENT PROJECT - LPG TERMINAL

Doc No: 256324-500-SP-ELE-008 Rev: C of 25

P:\Andheri\IndiaProject\256324 HPCL- LPG\10 Procurement\TENDER\21 Electrical Works Tender\Latest Tender -26-11-

09\Editable\Appendix-E-Spec. for Elec. Eqpt.doc

SPECIFICATION

FOR

ELECTRICAL EQUIPMENT TO BE

SUPPLIED BY CONTRACTOR






List of Content Page No

1 Scope 4

2 Equipment Specification 4

2.1 H.V. & L.V. Cables & Accessories 4

2.1.1 General Construction 4

2.1.2 Cable Accessories 6

2.1.3 Cable Glands 6

2.1.4 Cable Lugs 6

2.2 Busduct 6

2.2.1 Construction 6

2.2.2 Busbars 7

2.2.3 Busbar Supports 7

2.2.4 Space Heater 8

2.2.5 Earth Bus 8

2.2.6 Termination at the ends of Busduct 8

2.2.7 Special Chambers 8

2.2.8 Marking for Reassembly 8

2.3 L.T. Capacitor & APFC Panel 8

2.3.1 Constructional Features 8

2.3.2 Components 11

2.4 Power Distribution Panel & Lighting Distribution Panel with Energy Saver Feature

14

2.4.1 Constructional Features 14

2.4.2 Components 15

2.5 Energy Saver Feature in Lighting Distribution Board 16

2.6 Cable Trays 17

2.7 Flameproof & Industrial type Control Stations 17


2.7.2 Component Specification 18

2.8 Flameproof & Industrial Lighting and Power Panels 18



2.9 Flameproof and Industrial Light Fixtures & Junction Boxes 19


2.9.2 Lighting Fixtures 20

2.9.3 Control Gear Box (Integral Light Fitting) 20

2.9.4 Junction Boxes 21

2.9.5 Lighting Poles 21

2.10 Earthing 21

2.11 Flameproof & Industrial type plugs & Sockets 22








3 Makes of Components 23

4 Nameplate 23

5 Inspection, Testing and Acceptance 24

6 Packing and Despatch 24

6.1 Packing and Despatch of cable drums 24






1 Scope

1.1 This specification covers the requirements of design, manufacture, painting, inspection & testing

at manufacturer’s works and delivery to site inclusive of packing and transportation and

commissioning at site of all electrical equipments covered in clause 2.0 ‘Equipment

Specification’.

1.2 This specification shall be read in conjunction with Specification for “Electrical Installation

Tender” (Doc. No. 256324-500-RQ-ELE-003).

1.3 The equipment offered shall be complete in all respects. Any material or accessories, which may

not have been specifically mentioned in the specifications but which are usually necessary for

satisfactory, safe, trouble free, operation shall be provided without any extra charges.

1.4 It is not the intent to specify completely herein, all details of design and construction of the

equipment. However the equipment shall conform in all respects to high standards of

engineering, design and workmanship and shall be capable of performing in continuous

operation in a manner acceptable to the Owner/Consultant who will interpret the meaning of

drawings and specifications and shall have the power to reject any work or materials which, as

per his judgment are not in full accordance with requirement.

1.5 Vendor shall ensure the quality of workmanship for manufacture of equipment. The equipment

shall be supplied as per the latest applicable standards and as stipulated in this specification.

1.6 Quantity shall be worked out by vendor based on attached drawings. The vendor shall make his

own estimate of quantities for all items, such as equipment, power & control cabling system,

lighting system, earthing system, auxiliary power distribution, civil works, etc.

2 Equipment Specification

2.1 H.V. & L.V. Cables & Accessories

2.1.1 General Construction

The cables shall be suitable for laying in trays, trenches, ducts, pipe sleeves and conduits and for

underground-buried installation with uncontrolled backfill and possibility of flooding by water

and chemicals.

Outer sheath of all PVC and XLPE cables shall be black in colour and the minimum value of

oxygen index shall be 29 at 27 + 2 ° C. In addition suitable chemicals shall be added into the

PVC compound of the outer sheath to protect the cable against rodent and termite attack.

All cables covered in this specification shall be flame retardant low smoke (FRLS). Sequential

marking of the length of the cable in metres shall be provided on the outer sheath at every one

metre. The embossing /engraving shall be legible and indelible.

The overall diameter of the cables shall be strictly as per the values declared by the manufacturer

in the technical information subject to a maximum tolerance of ±2 mm up to overall diameter of

60mm and ±3mm for beyond 60mm.

2.1.1.1 PVC Control Cables

All control cables for use on low voltage systems shall be 650/1100 V grade with copper

conductor, PVC insulated with extruded PVC inner sheathed and extruded FRLS PVC outer

sheathed as per IS-1554 (Part-I) unless specified otherwise.

The core insulation shall be with PVC compound applied over the conductor by extrusion and

shall conform to the requirements of type 'A' compound as per IS: 5831. The thickness of

insulation and the tolerance on thickness of insulation shall be as per Table 2 of IS:1554 (Part-1).

Control cables having 6 cores and above shall be identified with prominent and indelible






numerals on the outer surface of the insulation. Colour of the numbers shall contrast with the

colour of insulation with a spacing of maximum 50 mm between two consecutive numbers.

Colour coding for cables up to 5 cores shall be as per Indian standard.

The inner sheath shall be applied over the laid-up cores by extrusion and shall be of PVC

conforming to the requirements of Type ST-1 PVC compound as per IS: 5831. The minimum

thickness of inner sheath shall be as per IS:1554 (Part-1). Single core cables shall have no inner

sheath.

The outer sheath for the cables shall be applied by extrusion and shall be of PVC compound

conforming to the requirements of type ST-1 compound as per IS: 5831. The minimum and

average thickness of outer sheath for unarmoured cables and minimum thickness of outer sheath

for armoured cables shall be as per IS:1554 (Part -1).

2.1.1.2 XLPE Power Cables

33 kV Power Cables : 33kV (E) grade, Stranded Aluminium conductor, Screened, XLPE

insulated, Galvanised steel strip Armoured, Extruded FRLS PVC outer sheathed generally

confirming to IS 7098 Part-2 1985.

L.V. Power Cables : 1.1kV grade, XLPE insulated, multi stranded conductor, single/multi core,

steel strip/wire armoured, Extruded PVC inner sheathed & Extruded FRLS PVC outer sheathed

confirming to IS 7098 (Part-1).

The conductors shall be stranded and compacted circular for all cables.

All 33 kV cables shall be provided with both conductor screening and insulation screening. The

conductors shall be provided with non-metallic extruded semi conducting screen.

The core insulation shall be with cross linked polyethylene insulating compound dry cured,

applied by extrusion. It shall be free from voids and shall withstand all mechanical and thermal

stresses under steady state and transient operating conditions. It shall conform to the properties

given in Table-1 of IS:7098 (Part -2).

The insulation screen shall consist of non-metallic extruded semi-conducting compound in

combination with a non-magnetic metallic copper screen. Unless specified otherwise, the copper

screen for all the three cores together shall be capable of carrying the single line to ground fault

current value and the duration specified in the data sheet.

The conductor screen, XLPE insulation and insulation screen shall all be extruded in one

operation by 'Triple Extrusion' process to ensure perfect bonding between the layers. The core

identification shall be by coloured strips or by printed numerals.

The inner sheath shall be applied over the laid up cores by extrusion and shall conform to the

requirements of type ST 2 compound of IS: 5831. The extruded inner sheath shall be of uniform

thickness. In case of single core cables, there shall be extruded inner sheath between insulation

metallic screen and armouring.

For multicore cables, the armouring shall be by galvanized steel strips as per method (b) of IS-

7098 (Part-2). If armouring is specified for single core cables in the data sheet, the same shall be

with H4 grade hard drawn aluminium round wire of 2.5 mm diameter.

The outer sheath of the cables shall be applied by extrusion over the armouring and shall be of

PVC compound conforming to the requirements of Type ST 2 compound of IS:5831. The

minimum and average thickness of outer sheath for unarmoured cables and minimum thickness

of outer sheath for armoured cables shall be as per IS:7098 (Part-2)

The thickness of the insulation, inner sheath shall be governed by values given in IS:7098 (Part-

2).






2.1.2 Cable Accessories

The termination and straight through jointing kits for use on the systems shall be suitable for the

type of cables offered as per this specification.

The accessories shall be supplied in kit form. Each component of the kit shall carry the

manufacturer's mark of origin.

The kit shall include all stress grading, insulating and sealing materials apart from conductor

fittings and consumable items .An installation instruction sheet shall also be included in each kit.

The contents of the accessories kit including all consumable shall be suitable for storage without

deterioration at a temperature of 45° C, with shelf life extending to more than 5 years.

2.1.2.1 Terminating kits

Heat shrinkable terminating kits shall be suitable for termination of H.V. cables to an indoor

switchgear or to a cable box of an outdoor mounted transformer. For outdoor terminations,

weather shields / sealing ends and any other accessories required shall also form part of the kit.

The terminating kits shall be from one of the approved makes.

2.1.2.2 Jointing kits

The straight through jointing kits shall be suitable for installation on overhead trays, trays in

cable cellar, concrete lined trenches, and ducts and for underground burial with uncontrolled

backfill and possibility of flooding by water and chemicals. These shall have protection against

any mechanical damage and suitably designed to be protected against rodent and termite attack.

The inner sheath similar to that provided for cables shall be provided as part of straight through

joint. The jointing kits shall be from one of the approved makes.

2.1.3 Cable Glands

Double compression type nickel plated brass cable glands shall be used. Rubber components

used in cable gland shall be of neoprene. Cable glands shall be of weatherproof or flameproof as

per area classification.

2.1.4 Cable Lugs

Cable lugs shall be of tinned copper for copper cable and aluminium lugs for aluminium cable,

crimping type & of reputed make.

2.2 Busduct

2.2.1 Construction

The Busduct shall be of box frame construction of Sheet Steel enclosure suitably braced to

withstand the maximum mechanical and electrodynamic forces.

The Busduct enclosure shall be fabricated from 2 mm thick Sheet Steel. Eddy current heating, if

applicable, shall be taken into account.

The section of the Busduct shall be rectangle & non-phase segregated. The degree of protection

shall be IP-55.The Busduct shall have fire barriers inside.

The Busduct enclosure shall be suitable for indoor/outdoor installation as specified. The outdoor

portion of Busduct shall be suitable for outdoor installation without any additional protection

from owner’s end. However, rain hood shall be provided as an additional protection for outdoor

installation. Canopy and proper fixing arrangements shall be provided for the same.






The Busduct shall be provided with removable top covers fitted with gaskets secured by

sufficient number of nuts, bolts to ensure that these covers are dustproof. All joints and covers

shall be provided with non-deteriorating type gaskets of neoprene between joints. These covers

shall be of suitable length for ease of removal and shall be arranged to give complete

accessibility to the busbars, joints, bends and supports, etc. The entire busduct shall be dust and

vermin proof. Louvers shall not be provided.

The design of Busduct enclosure shall be such that it will withstand the operating conditions

arising out of the following :

a. Normal operating conditions

b. Momentary short circuit currents

c. Rigours of adverse weather conditions, and

d. Combinations of above.

The busduct shall be provided with flanged ends to connect the busduct to transformer at one

end and switchgear at other end. These flanges shall match with corresponding flanges in the

equipment to which these are connected.

Vendor shall provide suitable flexible termination arrangement at 415V switchgear and

transformer ends. The busduct shall be supplied complete with all the hardware necessary for

making the terminations.

Proper wall sealing arrangements shall be provided at the wall where bus duct enters the

substation building. Busduct with wall mounting flange will be acceptable for the sealing

arrangement.

The enclosure shall be provided with suitable mounting lugs at suitable interval. The mounting

lugs shall be suitable for hanger type supports. Vendor shall design and indicate the supporting

arrangement for busduct.

Under Normal operating conditions, the surface temperature of the enclosure shall not exceed

70°C.

2.2.2 Busbars

The busbars shall be of electrical grade Aluminium flats adequately sized to carry maximum

specified continuous current & short circuit current for 1sec, at maximum site temperature

specified. The final temperature of busbars and connectors at joints between connector and

busbar should not exceed 75°C when carrying rated currents. Also the final busbar temperature

shall not exceed 250°C when specified short circuit current for 1sec duration flows through.

Current density of Busbars shall be 0.8 Amp/mm2 max.

All busbars shall be insulated with heat shrinkable PVC sleeves. All busbars shall be colour

coded such that on removal of any inspection cover the phases shall be identifiable.

Wherever required for long run of busduct, expansion joints with flexible strips shall be

provided to allow for expansion and contraction due to temperature variations arising out of

normal continuous current flow and short circuit current flow for specified duration. Minimum

one expansion joint shall be provided for each 3000 mm long straight length of busduct. In case

this is not provided, Vendor shall substantiate the same with Calculations.

2.2.3 Busbar Supports

The busbars shall be supported by non-deteriorating type (non-hygroscopic, non-carbonising,

Corrosion resistance) Solid core resin cast epoxy insulators of requisite electrical / mechanical

strength. The insulators shall be 1.1 KV grade for 415V system. The mechanical strength shall






be sufficient to withstand forces arising out of peak short circuit current. Each shipping section

shall meet this requirement separately.

Adequate Creepage distance shall be available on insulator to operate under high humid

conditions and effects of condensed moisture due to variations in temperature within busduct

due to different conditions of loading. Minimum number of skirts shall be 3 on each insulator.

The spacing of the insulating supports shall be decided on the basis of the fault withstand

capacity.

2.2.4 Space Heater

Busduct shall be provided with anti-condensation space heaters with controlling thermostats of

adequate capacity to maintain internal temperature above dew point to prevent moisture

condensation in busduct. Space heaters shall be rated for 240V, single phase, 50 Hz AC supply.

Space heater shall be provided on both sides of the fire barrier.

2.2.5 Earth Bus

Two earth bus of 50 mm x 8 mm aluminium shall run on the external side of the busduct through

the whole length of the busduct and shall be positively connected to the body of the busduct

enclosure. At both ends of the earth bus provision shall be made to connect it to main earthing

system.

2.2.6 Termination at the ends of Busduct

The busduct shall be provided with flexible at both ends for connecting it with transformer at

one end and 415V switchgear at other end.

The Flexibles shall be made of thin copper strips. The ends of the flexible shall be clamped by

copper plate. The ends of flexible shall be tin plated.

2.2.7 Special Chambers

To match the phase sequence of the two equipments connected by busduct, a suitable phase

cross over chamber shall be provided; if required, at suitable location. This chamber shall

generally be located in transformer yard.

2.2.8 Marking for Reassembly

All busduct parts like enclosure, adaptor box, rain hoods, enclosure covers, supports, busbar and

busbar fish plates shall be identified distinctly by clear numbers. These shall be indicated in

drawing.

2.3 L.T. Capacitor & APFC Panel

2.3.1 Constructional Features

The APFC Panels shall be totally enclosed, dust and vermin proof, free standing of uniform

height, cubicle multi-tier compartmentalised floor mounting type. The construction shall be

such that extension on the either side shall be possible.

The busbars, incoming and outgoing feeders compartment and capacitor storage space shall be

fabricated from cold rolled sheet steel panel of 2mm thickness. Removable type undrilled gland

plates shall be provided at bottom of the panel. Stiffeners shall be provided wherever necessary.






APFC Panels shall be provided with integral baseframe which shall be bolted/welded on the

cross members provided by owner. Amply dimensioned oblong holes shall be provided on the

base frame. The baseframe shall be of standard sections, re-rolled sections will not be

acceptable. Vendor shall give baseframe details in foundation drawing. Cross members or

foundation on which baseframe is mounted is excluded from Vendor’s Scope of supply.

The APFC Panels shall be properly ventilated by louvers and covered inside with wire mesh.All

cable entries shall be from the Bottom for both incoming and outgoing cables. Terminals shall

be located sufficiently away from gland plate to facilitate easy connection.

The construction of APFC Panel shall conform to a degree of protection to IP-42. All doors,

removable covers, gland plates and joints between adjacent sections shall be gasketed all round

with neoprene gaskets. Lifting facility shall be provided for each shipping section.

The live side of isolating switches must be fully insulated or shrouded. All main isolating

devices shall have provision for padlocking in the "OFF" position only and shall be interlocked

with door.

Each outgoing feeder shall be fixed type with the power switchgear & capacitors in the front

side. Rear access is not possible. The capacitor units shall be integral with the control panel unit

complete with internal wiring. Each capacitor feeder shall be provided with quick-make, quick-

break capacitor duty MCCB & contactor, "ON" and “OFF” indicating lamps, ammeter + ASS

and terminal blocks. Each compartment door shall be interlocked with switch.

The feeder compartment doors & cable alley doors shall be of lift-off type with hinges on one

side and turn lock on other side, which will ensure tight closing of the doors, making the

compartment effectively dust-proof. Care shall be taken while providing gaskets at hinged

points.

The size and layout of feeder compartments, busbars and cable alleys shall be such as to enable

easy maintenance of the equipment mounted inside.

The mounting height of all components on panel door shall be between 300 to 1800 mm from

floor.

The Vendor shall ensure that temperature within the cubicle is within acceptable limits and that

the heat from Capacitor Bank does not get transferred to the Switchgear Assembly. The Vendor

may consider using ventilation fans for effective heat removal.

Space heater for each cubicle / vertical panel shall be located at the bottom of the panel and shall

be controlled through a thermostat with an adjustable setting and a manually operated switch.

Panels shall have fluorescent light fittings for internal illumination with door switch.

2.3.1.1 Busbars

The busbar shall be made out of high conductivity electrolytic grade aluminium with adequate

cross section to carry continuous current.

The busbars shall be insulated with colour coded heat shrinkable PVC sleeves and supported by

non-hygroscopic material insulators with anti-tracking arrangements. Liberal clearance and

Creepage distances shall be provided for the busbar system to minimize the possibility of faults.

The busbar system shall be designed for fault level & maximum operating temp mentioned in

Electrical System Data.

The horizontal and vertical busbar compartment in Panel shall be totally segregated from rest of

the compartments and rendered totally inaccessible under normal circumstances. No equipment

shall be mounted on busbar chambers. All busbar compartments shall be provided with bolted

type gasketed covers.






Inter Panel Metal barriers of full height and width shall be provided between the bus

compartment and the out-going cable compartment.

2.3.1.2 Earthing

Horizontal earth bus bar located at the bottom shall be provided from end-to-end of the

assembly. Earth bus joints shall be solidly bolted. The earth bus shall be connected to the plant-

grounding grid at each end of APFC panel. Two numbers external earth terminal shall be

provided to adopt system earth conductor.

All non-current carrying metal parts of APFC panel shall be effectively connected to the earth

bus bar.

All metal doors and removable barriers shall be bonded to the rigid part of structure by stranded

insulated copper wires of 2.5 sq. mm minimum through earthing stabs.

The earth bus shall be connected at each end of APFC panel by accessible removable link.

2.3.1.3 Wiring & Terminations

Internal Power wiring shall be means of tinned copper strips with colour code at regular

intervals. All internal control wiring shall be with stranded conductor insulated copper wires of

2.5 sq. mm, 600 V / 1 kV grade & PVC insulated. Stranded conductors shall be terminated by

means of tinned copper lugs.

Conductor shall run without splices from terminal to terminal.

Sufficient space and supports shall be provided in the enclosure for field cable routing to the

terminals.

Incoming & Outgoing power terminals shall be bolted type. They shall be a minimum 50 mm

wide to provide proper bolt and washer application. Size of hole shall match size of cable lugs.

The power and control devices shall be furnished with finger-safe terminals. Terminals shall be

rated for 600 V A.C.

Control terminals shall be screw compression type.

Each wire shall be marked with the wire number & All terminal blocks shall be furnished with

white marking strips marked with terminal numbers in accordance with the wiring diagrams.

The terminal blocks shall be furnished with minimum 20% spare control terminals.

Colour Coding for internal panel wiring shall be as follows:

Power Wires : Red, Yellow, Blue for Phases.

AC Control Circuits : Red

DC Control circuits

Positive : Blue

Negative : Blue with white strip

Neutral Wires : Black.

Ground Wires : Yellow & Green

Interlock control circuits wired

from an external power source :

Yellow






2.3.2 Components

2.3.2.1 Power Factor Correction Capacitors:

Heavy-duty Film + Foil dielectric capacitors shall be used for the power factor correction. The

capacitors shall be designed to handle over voltages and over currents without reducing

capacitor life.

The Capacitors shall be dry type, hermetically sealed, constructed of All polypropylene two

layer film + foil dielectric with self-healing metallised electrodes. The capacitor cells shall be

impregnated with biodegradable, non-PCB impregnant.

Each capacitor shall be equipped with a Pressure Sensitive Interrupter, for protecting the

capacitor cell from rupturing.

The individual capacitor element shall have current limiting fuses 600 Volts, with wire internal

and blown fuse indicator shall be provided in each phase of each capacitor bank/ step. The fuses

shall provide protection against short circuit currents. The capacitor units shall be provided with

discharge resistors to reduce the residual voltage to 50V or less within 60 seconds of switching-

off. The capacitor shall be rated at 415V. The capacitor shall be suitable for + 10% over voltage.

The container of the capacitor shall be of high quality sheet steel with minimum joints and

suitable for mounting on a base channel. All mating surfaces shall be provided with neoprene

gaskets to render the enclosure dust / vermin proof.

Each 3 phase Capacitor unit shall be formed from basic units of 25/50 kVAr, by connecting

suitable nos. in series or parallel.

The Capacitor Bank shall be robust in construction, maintain rated output for at least 7 - 8 years

and shall have tropicalised design.

The container of the capacitor shall be of high quality sheet steel with minimum joints and

suitable for mounting on a base channel.

The capacitor banks formed from individual units shall have sheet steel cable box complete with

copper links suitable to receive PVC insulated PVC sheathed, copper conductor, un-armoured

cables.

Each Capacitor Bank shall be provided with 2 nos. external earth terminals each complete with 2

plain and 1 spring washers. This Earthing bolt shall be connected to body earth.

The connection from active elements of the capacitor to the terminal box shall be through studs

fixed to cover properly sealed to make the capacitor unit hermetically sealed. The active

elements shall be mixed dielectric type or All Polypropylene.

Each Capacitor Bank shall be fitted with Perspex nameplate.

2.3.2.2 Automatic power factor controller relay

The controller shall be microprocessor based (with adjustable control), having auto / manual

control selection mounted on the front of the panel with indication having minimum 16 steps.

The control circuit shall sense the power factor, KVAR of the connected power system and

based on the desired power factor selected from the front of the panel, it shall close / open the

output relay contacts with a definite time lag to switch ON & OFF the required capacitor banks.

The controller shall tap the reference voltage from the incoming voltage 3 phase, 4- wire supply.

Reference current signal shall be sensed from current transformer with 5A secondary connected

in middle phase mounted in the Low Voltage Switchgear (supplied by others).

The controller shall have a setting range for target power factor from 0.80 inductive to unity. To

avoid 'hunting', minimum set KVAR selection shall be available on the front of the panel. An

auto/manual selector switch shall be provided on the controller for control of capacitor banks






with the set ranges of target power factor and % KVAR, in auto mode and without these ranges

in manual mode.

Push buttons shall be provided on the controller to switch ON & OFF the capacitor banks in

manual mode.

The Controller shall be programmed for setting the timing sequence to take care of the discharge

time of the capacitor. The switching sequence shall be such, as to permit utilization of all the

capacitor banks, thereby increasing the operational life of the capacitors.

The power factor controller relay unit shall comply with the following standard features: -

a. Digital display of operating conditions viz., capacitor step sizes, number of switching

operations per step, defective capacitor step, etc.,

b. Digital display of system parameters viz., active, reactive, and apparent power, power factor,

voltage, current, thermal current load, harmonics, load flow direction etc.,

c. The controller shall have protection against over voltage and current path reversed

connection.

d. Manual/Automatic selector switch for selecting the controller mode of operation.

e. Variable switching programmes viz., fully automatic, conventional and manual operation.

f. Monitoring of out of limit conditions with visual alarm viz., over and under compensation,

power loss of capacitors, current overload, harmonic overload etc.,

g. Adjustable switching ON or OFF time delay from 10 to 60 seconds.

h. Fault output relay for signalling of target power factor is not reached.

i. Automatic rotational switching program to ensure that the steps are used equally.

j. A voltage transformer (control transformer) shall be provided within APFC enclosure for

control power.

k. RS485 – Interface port for data transmission

l. Fault signaling contact for control alarm.

2.3.2.3 Air circuit breaker

Incomers of the APFC Panel shall be provided with ACB for incomer rating 2000Amp. Air

circuit breakers shall confirm to the following requirements:-

Short Circuit breaking capacity (Ics) shall be minimum 50 kA RMS Symmetrical at 415 Volts.

Also, the Short Circuit Withstand capacity shall be 50 kA minimum, for 1 sec at 415 Volts.

The air circuit breaker shall be manually and electrically operated, fixed type equipped with

motor wound spring charged closing & trip mechanism. The spring charging motor shall be

suitable for 110 V, DC supply.

Means shall be provided for slow closing and opening of the breaker for maintenance purpose

and for manual charging and closing of electrically operated breakers during emergencies.

Following safety features and accessories shall be provided in the breaker:-

• It shall not be possible to open the compartment door when the circuit breaker is ON.

• Heavy duty self-aligning earth contact.

• Anti pumping circuit shall be provided such that the breaker shall not reclose after tripping

even though a close signal may be continuously present.






• Position (TRIP-NEUTRAL-CLOSE) Selector Switch with spring return from Trip/Close to

Neutral.

The CB shall be provided with microprocessor based direct acting protection releases for

overload, short circuit, earth fault & Under-voltage. The releases shall be adjustable type.

The Circuit Breaker shall be provided with mechanical ON/OFF, TRIP and SPRING

CHARGED, DISCHARGED indication, T/N/C control switch, mechanical trip push button,

mechanical ‘close' push button, and padlocking facility.

2.3.2.4 Moulded Case Circuit Breaker (MCCB)

All the outgoing feeders shall be equipped with MCCBs.

MCCB shall be equipped with adjustable instantaneous magnetic trip element. The Short Circuit

Breaking capacity (Ics) shall be minimum 50 kA RMS Symmetrical at 415Volts. Also, the Short

Circuit Withstand capacity shall be 50 kA minimum, for 1 sec at 415 Volts.

MCCB shall be designed for application in individual Capacitor bank circuit. They shall operate

on the magnetic principle with a current sensing element in each pole to provide short circuit

protection.

MCCB shall be triple pole manually operated with handle. A padlocking facility shall be

provided to lock the unit MCCB operating handle in the ‘OFF’ position.

MCCB operating mechanism shall be quick-make, quick-break and trip-free. Trip free

mechanism shall be independent of manual operation.

2.3.2.5 Power contactors

All contactors shall be 3 pole air - break, magnetic, capacitor duty type. The rating of contactor

shall be suitably assigned.

The individual capacitor bank/step shall be switched using NEMA rating magnetic contactors

suitable for switching capacitive currents.

The minimum life expectancy of the contactor shall be one million switching operations.

Each Power contactor shall have 2 NO and 2 NC auxiliary contacts wired upto terminal block

for Purchaser's use.

2.3.2.6 Indicating & Measuring Instruments

Indicating lamps shall be LED type. Voltage rating of the bulb shall match control circuit

voltage.

A suitable range of analog ammeter with selector switch and analog voltmeter with selector

switch shall be provided for the incoming feeder.

2.3.2.7 Current transformer

CT shall be epoxy moulded cast resin. Manufacturer shall check the saturation factor, ratio, and

burden and accuracy class of CT before mounting them. Name plates shall be provided on each

CT

The terminals of CT shall be stud type. Loose leads of CT are not acceptable.

The CT’s shall withstand thermal and dynamic stresses due to max. short circuit current as

specified.






2.4 Power Distribution Panel & Lighting Distribution Panel with Energy Saver Feature

2.4.1 Constructional Features

The general construction details of the board shall be subject to purchaser's approval and shall be

in line with IS-8321 for Factory's Build Assemblies.

The Power & Lighting Distribution Panels shall be fabricated from CRCA sheet steel of

minimum thickness 2 mm. The load bearing members and the doors with large instruments shall

be fabricated from suitably thicker sheets. Stiffeners shall be provided, wherever required.

The individual panels of the distribution board shall be identical in depth and height and when

bolted together shall give appearance of one continuous panel. The Panels shall be complete

with the base frame of min. height of 75 mm.The cable entry of distribution boards shall be from

bottom with removable undrilled gland plate.

The Panels shall have totally segregated busbar chamber, cable alley and feeder compartment.

Each feeder in the board shall be mounted in separate compartments. The compartment shall be

totally segregated so that, in case of a fault in any feeder, the damage is restricted to that

compartment only. The barriers shall be used to achieve compartmentalisation.

The compartment doors shall be provided with concealed hinges and thumb screws with

retaining washer. The spacing of thumb screws shall ensure proper compression of gasket. The

compartment doors shall be interlocked with the switch of the feeder such that the door can be

opened only when the switch is off.

The cable alley shall be provided with hinged doors & shall be provided with arrangement for

fixing cable clamps.

The distribution board shall be suitable for extension on either side.

The Distribution Board shall be single front & shall have front access only, both for maintenance

and operation. The boards shall be suitable for placing against the wall.

Gaskets shall be provided between all joints, beneath the door and gland plates to ensure

effective dust and vermin proofing. The hardware used shall be high tensile strength steel with

zinc passivation or chromium plated.

A separate vertical section shall be provided for the main incoming power feeder.

Adequate lifting lugs / hooks shall be provided for each shipping section.

The horizontal and vertical busbar compartment in PDP & LDP shall be totally segregated from

rest of the compartments and rendered totally inaccessible under normal circumstances. The

busbar chamber shall be adequately sized and totally enclosed and at the same time maintaining

the temperature rise of busbars within the permissible values as per relevant standards.

Temperature rise of offered busbars shall be specifically stated in the offer by VENDOR. The

busbar chamber shall be complete with bolted cover. No equipment shall be mounted on Busbar

chamber.

The Degree of Protection of LDP & PDP shall be IP-42 or better

LDP shall be provided with lighting transformer to reduce fault level.

2.4.1.1 Wiring & Terminations

All the equipments covered in this specification shall be supplied completely wired internally to

components and terminal blocks and ready for purchaser’s external cable connections.

The Incomer Terminals shall be suitable for termination of Aluminium armoured cables as

indicated in SLD. If Incoming MCCB/MCB terminals are not adequate to receive the incoming

cable size additional terminal shall be provided.






The Terminal Block provided for connecting Outgoing Cables shall have terminals suitable for

terminating the Aluminium armoured cables.

The connection between feeders and the busbars shall be with links of adequate size in case of

feeders above 63 amperes and with 650 V grade PVC insulated copper / aluminium conductor in

case of feeders of rating below 63 ampere.

Terminal blocks shall be rated 600 V. Terminals shall be permanently marked with white

marking strips in accordance with the Wiring Diagram. The terminal blocks shall be furnished

with minimum 10% spare terminals

All cable terminations shall be via lugs. Tin-plated copper lugs suitable for aluminium

conductors shall be provided for the main incoming power feeder. Fork type tin plated copper

lugs shall be provided in the incoming line section for connecting the main grounding conductor.

2.4.1.2 Earthing

The Distribution Board shall be provided with continuous earth busbar complete with 2

terminals for connecting the earth busbar to the system earthing grid. Separate earth A1.busbar

shall be provided throughout inside the panel & shall be brought out at ends.

2.4.2 Components

2.4.2.1 Switches

The switches shall be heavy duty, load break quick break complete with shrouding for incoming

and outgoing terminals.

The switches shall be complete with door interlocking mechanism wherever required in order to

provide interlocking with the compartment door such that the door can be opened only when the

switch is off.

The switch handle shall have clear indication for the ON and OFF position of the switch.

2.4.2.2 Fuses

The fuse shall be HRC type and shall conform to relevant Indian Standards.

The fuses shall be link / diazed type.

The fuse shall be provided with mechanism to indicate fuse blow off.

2.4.2.3 MCCB/ MCB/ ELCB

MCCB / MCB shall be suitable for the fault level as achieved by Lighting Transformer.

The MCCB's shall be complete with over-current and short circuit tripping types.

MCCB shall be triple pole manually operated with handle. A padlocking facility shall be

provided to lock the MCCB unit-operating handle in the ‘OFF’ position. MCCB operating

mechanism shall be quick-make, quick-break and trip-free. Trip free mechanism shall be

independent of manual operation.

ELCB shall be of reputed make.

2.4.2.4 Power contactors

All contactors shall be air break, magnetic conforming to AC3 category of duty.

All power contactors shall have a minimum of 2 NO + 2 NC auxiliary contacts. The auxiliary

contractors shall have 4 No + 4 NC contacts. The spare contacts shall be wired up to the

terminal block.






2.4.2.5 Indicating & Measuring Instruments

The indicating and measuring instrument such as voltmeter, ammeter, MFM meter shall be flush

mounting type. The instruments shall be mounted on the compartment door and the mounting

height shall be above 300 mm but below 1800 mm from the base of the switch board.

The indicating lamps wherever provided shall be filament type complete with series resistance.

2.4.2.6 Current transformer

CT shall be cast resin. They shall be mounted on a stationary part of switchgear. Manufacturer

shall check the saturation factor, ratio, burden and accuracy class of CT before mounting them.

Name plates shall be provided on each CT

The terminals of CT shall be stud type. Loose leads of CT are not acceptable.

The CT’s shall withstand thermal and dynamic stresses due to max. short circuit current as

specified.

2.4.2.7 Lighting Transformer

The plant lighting system shall be fed by the lighting transformer. The lighting transformer shall

be 415 / 415 V, three phase delta-star connected, dry type with OCTC, located inside the

respective lighting distribution board.

Lighting transformer shall be sized to take care of the total lighting load of the plant with a

provision for 10% extra capacity and suitable impedance to reduce the short circuit withstand

capacity. (Refer Single Line diagram for MLDP, EMLDP & Yard Lighting DP). Manufacturer

shall submit lighting transformer calculation for approval.

2.4.2.8 Busbars

The busbar shall be of high conductivity electrolytic grade aluminium with adequate cross

section to carry continuous current with temperature rise limited to value specified in Indian

Standard.

The busbars shall be insulated with colour coded heat shrinkable PVC sleeves and supported by

non-hygroscopic material insulators with anti-tracking arrangements. Liberal clearance and

Creepage distances shall be provided for the busbar system to minimize the possibility of faults.

The joints between busbar as well as between busbars and the links for outgoing connections

shall be complete with spring washers.

2.5 Energy Saver Feature in Lighting Distribution Board

Energy saver feature in LDP shall be with PLC based controller with software interface via RS-

232 and Ethernet, circuit breaker for short circuit & overload protection. The password protected

software shall communicate with the controller to display current schedule and update or add any

new programmes. Energy saver panel shall have LCD display with backlight, it shall display

time/date and current preset level, power & energy used. It shall also have fully programmable

daily/monthly/yearly calendar with holiday scheduler for controlling each outgoing circuit. It

shall have auto start/shutdown facility with 0-30 minute ignition cycle.

The facility operator shall be able to access locally or remotely by using the software & manage

any of the elements listed below:

Schedule or manually implement automatic energy reduction levels and on/off switching

Participate in peak shaving/load shedding/utility energy requirements without disruption of work

View power usage and energy consumption of each circuit






The size and layout of feeder compartments, busbars and cable alleys shall be such as to enable

easy maintenance of the equipment mounted inside.

Space heater for each cubicle / vertical panel shall be located at the bottom of the panel and shall

be controlled through a thermostat with an adjustable setting and a manually operated switch.

Panels shall have fluorescent light fittings for internal illumination with door switch.

2.6 Cable Trays

2.6.1 Cable trays shall be ladder type prefabricated hot dip galvanised sheet steel of thickness 2.5mm

trays.

2.6.2 GI Coating thickness shall be of 75 micron.

2.6.3 Dimension details of cable trays shall be provided as per attached Drawing No. 256324-500-

ELE-4801 in Appendix-I.

2.6.4 Outer most tier of all vertical cable trays shall be covered with GI sheet for protection against

physical damage to cables.

2.6.5 Cable trays shall be covered by removable top covers on upper most tier allowing adequate

ventilation in following cases where:

• Mechanical damage of cables is likely to occur during maintenance in the plant.

• Oil or spillage of chemicals can be expected.

• Protection from exposure to sun is required.

2.6.6 The cable trays shall be supplied in standard lengths of 3000 mm and clear width of trays shall

be 150 (for perforated type trays), 300, 500, 700, 900 mm (for ladder type trays).

2.6.7 GI cover sheet shall allow adequate ventilation to the cables and shall be in standard length of

3000 mm, flanged on both sides for fixing on cable tray. Covers shall be complete with required

GI hardware.

2.6.8 The adjacent cable trays shall be supported at every 2 to 2.5mtr depending on tray width.

2.6.9 Clamping arrangement shall be done on the length of cable trays at every interval of 1000 mm

for horizontal trays & 300/500 mm for vertical trays.

2.7 Flameproof & Industrial type Control Stations

2.7.1 Construction

Flameproof control station shall be made of cast light metal alloy and shall be free from

frictional sparking hazard. The magnesium content in the alloy shall be as per IS-13346.

Flameproof enclosure shall be suitable for zone 1 & 2, gas group IIA / IIB & temperature class

T-3. The enclosures of the industrial control station shall be made of CRCA sheet steel (2 mm),

dust & vermin proof and accessories suitable for installation in Industrial outdoor areas and shall

have enclosure protection as per IP-55.

The control stations shall be suitable for use in outdoor open locations and shall have IP-55

degree of protection. They shall preferably be provided with integral canopy. However, where

the enclosure has been certified without integral canopy, a separate canopy can be accepted. The

separate canopy shall be made of at least 14 SWG (2mm) galvanised sheet steel or FRP. The

canopy shall be suitable for providing protection against rain from top and two sides.

Unless otherwise specified all control stations shall be suitable for 240 V AC control supply.

The control stations shall be provided with gaskets made of non-inflammable and self-

extinguishing material.






The enclosures shall be treated and prepared for painting with two coats of epoxy paint with

final colour shade (both internal and external) as Silver grey No. 628 (IS-5)

All accessories like nuts, bolts, washers etc. shall be made of stainless steel SS-304.

The control stations shall be provided with two earthing studs with lugs on the external surface

of the enclosures suitable for termination of 8 SWG GI wire.

Each control station shall be provided with 2 nos. bottom cable entries and 1 no. flameproof

nickel plated brass sealing plug.

The control stations shall have external fixing lugs for mounting on wall or column. The holes

provided on these lugs shall be of oblong type.

2.7.2 Component Specification

Push buttons for START and STOP shall be of GREEN and RED colour respectively. Unless

otherwise specified, each push button shall have one normally open and one normally closed

contact. The STOP push button shall be mushroom type with stay put feature and lockable in

pressed position.

Selector switches shall have three/ four positions (Local, Off & Remote) for Local Control

Station. Unless otherwise specified, all selector switches shall have minimum two poles for each

position. Each position shall be indelibly marked on the control station.

All ammeters shall be of moving iron type having an accuracy class of 3 and suitable for 1

Ampere CT secondary. Unless otherwise specified, min. size of ammeter shall either be 50 mm x

50 mm. 80% of the scale length shall cover 100% of the CT primary current uniformly and the

balance 20% of the scale shall cover 100-600% of the CT primary. A red mark corresponding to

the full load current of the motor shall be provided on the ammeter dial. The ammeter front glass

shall be toughened (Type 'A' glass).

All push button and control switch contacts shall be rated for min. 5 Amps at 240 V AC-15.

Indicating lamp(s) wherever provided shall be clustered LED type (with minimum 3 nos. LEDs,

preferably connected in parallel), mounted inside an enclosure of minimum diameter of 15mm.

2.8 Flameproof & Industrial Lighting and Power Panels

2.8.1 Construction

The enclosures of the flameproof lighting and power panels shall be made of cast light metal

alloy and shall be free from frictional sparking hazard. The magnesium content in the alloy shall

be as per IS-13346. Flameproof enclosure shall be suitable for zone 1 & 2, gas group IIA / IIB &

temperature class T-3. The enclosures of the industrial lighting & power panels shall be made of

2mm thick sheet steel and shall be dust & vermin proof. All metal surfaces shall be cleaned free

of rust. The enclosures shall be sized to facilitate easy maintenance and heat dissipation.

Panels shall be indoor / outdoor type as specified. Indoor type panels shall have IP-42 degree of

protection and panels located in outdoor open locations shall have IP-55 degree of protection.

The panels shall be suitable for surface or flush mounting on wall surface as specified. They

shall preferably be provided with integral canopy. However, where the enclosure has been

certified without integral canopy, a separate canopy can be accepted. The separate canopy shall

be made of at least 2mm galvanised sheet steel or FRP. The canopy shall be suitable for

providing protection against rain from top and two sides.

The lighting and power panels shall be provided with gaskets made of non-inflammable and self-

extinguishing material.







final colour shade (both internal and external) as Silver grey shade 628 (IS-5)


All the non-current carrying metallic parts of the panel shall be inherently bonded together. Each

lighting and power panel shall be provided with two earthing studs with lugs on the exterior of

the panel enclosure suitable for termination of 10 mm dia GI wire rope.

Each outgoing feeder shall be provided with distinct terminals for phase, neutral and earth. The

terminal block enclosures shall be adequately sized to properly terminate the cables by taking

into account the required bending radii of cable cores and shall have the following minimum

gland to terminal distances:

Conductor Size Up to 2.5

mm2

Above 2.5 mm &

Up to 10 mm2

Above 10 mm2 &

Up to 35 mm2

Above 35 mm &

Up to 70 mm2

Gland to terminal

distance 40 mm 100 mm 150 mm 300 mm

The panels shall be provided with suitably sized cable entries at the bottom/ sides, for incoming

and outgoing cables. Flameproof nickel plated brass sealing plugs shall be supplied, for plugging

the unused cable entries. The quantity of sealing plugs shall be equal to 20% of the total number

of outgoing cable entries.

The panels shall have external fixing lugs for mounting on wall or column. The holes provided

on these lugs shall be of oblong type.


Busbars in the lighting and power panels shall be made of high conductivity copper, and shall be

supported by non-hygroscopic insulators. Busbars shall be colour coded for identification of

phases and neutral.

Unless otherwise specified, the incomer shall have one no. TP MCB with neutral link, 3 nos.

fuses for maintenance and 3 nos. 30mA single phase ELCB for each circuit.

Unless otherwise specified, the outgoing feeders shall be provided with double pole 10A MCBs

having overload and short-circuit releases.

Unless otherwise specified, all MCBs shall be with 16kA (M9 category) interrupting capacity.

The ELCB shall be hand reset type. One no. door mounted reset push button shall be provided.

The operating knobs (ON/ OFF/ RESET) shall be provided with a suitable rack and pinion

arrangement for operating them smoothly from outside.

Wherever the size of incoming cable to lighting, power panels is more than 35 sq.mm a suitable

cable adapter box shall be provided and attached to the panel. The incoming cable leads shall be

connected to terminal block (bolted type terminals) of required size. This terminal block shall be

connected to TPN incomer unit through separate PVC insulated copper conductor wires/bus bars.

Sufficient space shall be provided (minimum 300mm) between gland plate and the bottom of

terminal block for easy termination.

2.9 Flameproof and Industrial Light Fixtures & Junction Boxes

2.9.1 Construction

The enclosures of the flameproof lighting fixtures, control gear box and junction boxes shall be

of cast light metal alloy and shall be free from frictional sparking hazard. The magnesium content

in the alloy shall be as per IS-13346. Flameproof enclosure shall be suitable for zone 1 & 2, gas






group IIA / IIB & temperature class T-3. The enclosure of the industrial lighting fixtures, control

gear box and junction boxes shall be of CRCA sheet steel, dust & vermin proof.

All equipment shall be suitable for use in outdoor open locations and shall have IP-55 degree of

protection.

The enclosures shall be provided with gaskets made of non-inflammable and self-extinguishing

material.

The enclosures shall be treated and prepared for painting with two coats of epoxy paint with final

colour shade (both internal and external) as Silver grey shade 628 (IS-5)


All equipments on single phase supply shall be provided with an independent earth terminal with

lug inside the enclosure for terminating the third (earth) core of the cable and shall have facility

for looping.

2.9.2 Lighting Fixtures

Glass used for lighting fixture shall be clear and suitable for use under conditions involving

exceptional risk of mechanical damage.

Well glass lighting fixture for Zone-2 classified area shall meet requirement of IS-8224.

Mechanical strength of well glass shall satisfy requirement of IS-2206 (for type A glass) for

flame proof lighting fixtures, and IS-6381 for Div. 2 lighting fixtures. All well glass fixtures

shall be provided with a protective wire cage using minimum 5 mm welded steel construction

and having mesh dimensions not exceeding 50mm x 70mm.The material of the cage shall be

galvanised steel or epoxy powder coated mild steel.

The fixing parts of the enclosure, which are to be opened for replacement of bulb, shall be so

fastened that they can be unfastened only with special tools.

The lighting fixtures in Zone-2/ Zone-1 area, shall have approved type enclosed break lamp

holder and complete enclosure certified as having restricted breathing type construction. In case

of lighting fixtures, the holder shall additionally have a spring-loaded lock to hold the lamp in

position and to prevent the lamp coming off loose in the holder. Lamp holder shall be Edison

screw type.

All lighting fixtures shall be provided with 2 no. threaded entry and 1 no. double compression

nickel plated brass cable gland. The glands shall be suitable for the specified cable size. All the

fixtures having double cable entry shall be supplied with 1 no. nickel plated brass plug for

sealing the unused entry.

The top of all well glass lighting fixtures shall be identically drilled/ threaded to facilitate

installation on pole/ column or ceiling.

The flood lighting fixtures shall be supplied with adjustable mounting arrangement both in

horizontal and vertical plane.

All lighting fixtures shall be provided with suitable mirror-polished aluminium internal reflector

of suitable thickness to ensure adequate mechanical strength.

2.9.3 Control Gear Box (Integral Light Fitting)

Lighting fixtures suitable for discharge lamps shall be provided with power factor correction

capacitor, choke starter etc., housed in separate compartment. The choke shall be copper wound.

The complete control gear shall have power factor not less than 0.9.

The control gear boxes shall be provided with 3 nos. entries and 3 nos. double compression

nickel plated brass cable glands. The glands shall be suitable for the specified cable size. 20% of






the control gear boxes shall be supplied with 1 no. nickel plated brass plug for sealing the unused

entry.

Control gear box for flame proof fixtures shall be flameproof type unless specified otherwise.

2.9.4 Junction Boxes

Unless otherwise specified, the junction boxes shall be of flameproof construction suitable for

zone 1 & 2, gas group IIA/IIB, temperature class T-3. Each junction box shall be complete with

requisite number of cable entries and double compression flameproof nickel plated brass cable

glands to suit the specified cable size and flameproof sealing plugs.

2.9.5 Lighting Poles

Lighting poles shall be fabricated from MS steel tubular pipes with joints, swaged together when

hot and bevelled on outside edges.

Poles shall be coated with bituminous preservative solution on the ground portion of the outside

surface. Remainder of the outside surface shall be given two coats of red oxide primer and

finished with two coats of aluminium paint.

The pole shall have a marshalling box/Junction Box near the bottom to contain HRC fuses, a

neutral link, an earth stud and terminal block. Each pole shall have two distinct earthing points

for connecting to the plant earth grid.

2.10 Earthing

Earthing system shall comply with the requirements of IS-3043 and IEEE-80.

All materials and hardware to be supplied by the contractor shall be new, unused and of best

quality and shall conform to the specifications given here under and to latest specifications of

Bureau of Indian Standards. Contractor shall bring material samples to site and get it approved

by Engineer-in-charge before installation.

The following conductor materials are proposed for the earthing system :

i) Conductor above ground level, cable

trenches and along cable trays GI Earth strip

ii) Conductors buried in earth and concrete GI Earth strip

iii) Outdoor structure, Plant, Earth pits GI pipe electrodes of size:3 Mtr. Length &

65mm dia.as per IS 3043 & standard drawing

iv) TRF Neutral Earth pits & DG Neutral

Copper Plate electrodes of size 600 x 600 x

10mm with 2 Nos.50 x 6mm G.I.Earth strips

as per IS 3043.

v) Lightning protection earth pits GI pipe electrodes of size:3 Mtr. Length &

65mm dia.as per IS 3043

The galvanizing of the earthing material shall be done as per IS 2629-1985. Earth Electrodes

shall have disconnecting facility. The rate shall be inclusive of excavation, Earth Electrodes

fixing, backfilling, construction of earth pit chamber and earth pit cover, etc.

Earthing conductors in the plant shall be laid in the form of a grid. Earthing leads of transformer

& D.G.Set’s neutral shall be directly connected to two separate G.I. earth plate electrodes

whereas, in the plant, outdoor structure, towers, tanks, building columns, loading racks, pipe

racks, vessel & heat exchanger etc shall have two distinct earth connections.






All interconnections of the earthing grid conductors shall have welded type joints except at

electrodes with disconnecting facility and at equipment with bolted connections. All indoor

earthing grids shall be suitably interconnected to the external earthing grid.

Steel strips/conduits, cable trays etc shall not be used as earth continuity conductors.

Earth pit marker showing details as indicated in Installation drawings 256324-500-ELE-4803-

Sh-1 attached in Appendix-I shall be provided.

2.11 Flameproof & Industrial type plugs & Sockets

2.11.1 Construction

The enclosures of the flameproof plugs, sockets & transformers shall be made of cast light metal

alloy and shall be free from frictional sparking hazard. The magnesium content in the alloy shall

be as per IS-13346. Flameproof enclosure shall be suitable for zone 1 & 2, gas group IIA / IIB &

temperature class T-3. The enclosures of the industrial plugs, sockets & transformers shall be

made of CRCA sheet steel, dust & vermin proof. The enclosures shall be sized to facilitate easy

maintenance and heat dissipation.

The equipment shall be suitable for use in outdoor open locations and shall have IP-55 degree of

protection. The sockets for fixed installation, i.e. 415 V three phase sockets and 240 V single

phase sockets, shall be provided with integral canopy. However, where the enclosure has been

certified without integral canopy, a separate canopy can be accepted. The separate canopy shall

be made of at least 2mm galvanised sheet steel or FRP. The canopy shall be suitable for

providing protection against rain from top and two sides.

The enclosures shall be provided with gaskets made of non inflammable and self extinguishing

material.


final colour shade (both internal and external) Silver grey No. 628 (IS-5)


All the non current carrying metallic parts of the equipment shall be inherently bonded together.

The TPN sockets shall be provided with two earthing studs, with lugs on the exterior of the

enclosure, suitable for termination of 10 mm dia GI wire rope. Internal earth terminal shall be

provided in each enclosure for all single plugs and sockets for connecting the earth core of the

cables.

The terminal block enclosures shall be adequately sized to properly terminate the cables by

taking into account the required bending radii of cable cores and shall have the following

minimum gland to terminal distances:

Conductor

Size

Up to 2.5 mm2 Above 2.5 mm &

Up to 10 mm2

Above 10 mm2 &

Up to 35 mm2

Above 35 mm &

Up to 70 mm2

Gland to

terminal

distance

40 mm 100 mm 150 mm 300 mm

The sockets shall be provided with 2 nos. suitably sized cable entries at the bottom for specified

cable sizes. The plugs shall be supplied with 1 no. suitably sized cable entry for specified cable

size. Each socket shall be supplied with 1 no. flameproof nickel plated brass sealing plug, for

plugging the unused cable entry.

The sockets shall have external fixing lugs for mounting on wall or column. The holes provided

on these lugs shall be of oblong type.







The sockets shall be provided with a switch and a mechanical interlock so as to break the

electrical circuit before the plug is completely withdrawn and make the circuit after the plug is

fully inserted.

In order to prevent accidental removal of plug from socket, the engagement and disengagement

shall be by two separate and distinct movement and positions.

Unless otherwise specified, 415V, 63A three phase flameproof plug and socket meant for

welding receptacle/ any other three phase auxiliary load, shall be provided with 5 pins

(3P+N+E).

5 pin socket shall be provided with 63A, four pole (TPN) heavy duty switch.

Both 24V and 240V, 15A single phase flameproof plug and socket shall be provided with 3 pins

(2P+E).

Provision shall be made so that it shall not be possible to insert 24V plug on to a 240V socket.

The sockets shall be provided with either a spring loaded hinged cover, or with a cap connected

through metallic chain, to close the same when not in service.

Scraping earth connection shall be provided between the plug and socket. Earth pin of plug shall

first engage with earth pin of switch socket.

The plug assembly shall be mechanically rugged, light and shall not unduly stress the socket or

its own pins when fitted on to the socket. The diameter of the earth pin of the plug and socket

shall be at least 1.1 times the diameter of the phase pins.

3 Makes of Components

Makes of components shall be as per Recommended sub-vendor list attached in tender

document.

4 Nameplate

Permanent non-corrosive nameplate with engraved white letters on black background indicating

the switchgear designation shall be fixed at the top of the central panel.

Name plates shall contain the following information:

First line : Equipment Item No.

Second line : Equipment Description

Third line : Equipment Rating.

Fourth Line : System voltage.

The following information shall be inscribed on a non-destructive, corrosion-resistant, indelible

name/rating plate attached to the inner side of the unit enclosure door:

Purchaser's order number.

Year of manufacture.

Name of Manufacturer.

Type and serial number of unit.

Purchaser’s Equipment Number.

Nominal input current and voltage (incl. nature of current & number of phases).

Rated nominal output current and voltage.

Nominal DC / battery voltage.

Ingress protection degree.

All terminals of equipment and components shall be identifiable by alphanumerical markings in

accordance with the Manufacturer's drawings. Terminals of input and output supply cables shall






be clearly and uniquely marked to indicate their purpose and the phase/polarity of the supply.

All wires shall be marked according to the electrical diagrams with closed loop markers

(ferrules) or stamped. Danger labels shall have black letters on a yellow background.

5 Inspection, Testing and Acceptance

During fabrication, the equipment shall be subjected to inspection by Owner or by an agency

authorised by the owner, if specified/ agreed in Inspection Test Plan. Manufacturer shall furnish

all necessary information concerning the supply to Owner's inspector. All routine/ acceptance

tests shall be carried out at manufacturer's works under his care & expense.

Type test certificates from CMRI or equivalent test house, applicable CCE/ DGFASLI/ DGMS

approval certificates, BIS license and original drawings referred in type test certificates shall be

shown to the inspection agency on demand during inspection. The certificates and BIS license

must be valid at the time of despatch.

Test certificates of bought out components shall be shown to the inspection agency on demand

during inspection.

All equipments shall be subjected to various acceptance tests as per standards but not limited to

the following:

General visual inspection

Dimensional inspection

Verification of mechanical and electrical operations

Dielectric tests

Routine pressure test

Any other routine and acceptance test as per applicable standards.

6 Packing and Despatch

All the equipment shall be divided into several sections for protection and ease of handling

during transportation. The equipment shall be properly packed for the selected mode of

transportation, i.e. by ship/ rail or trailer, and shall be wrapped in polythene sheets before being

placed in crates/ cases to prevent damage to finish. The crates/ cases shall have skid bottom for

handling. Special notations such as 'Fragile', 'This side up', 'Center of gravity', 'Weight', 'Owner's

particulars', TO no.' etc., shall be clearly marked on the packages together with other details as

per purchase order.

The equipment may be stored in a covered shed for long periods before installation. The packing

should be suitable for such storage.

6.1 Packing and Despatch of cable drums

Cables shall be despatched in non-returnable wooden or steel drums of suitable barrel diameter,

securely battened, with the take-offend fully protected against mechanical damage. The wood

used for construction of the drum shall be properly seasoned, sound and free from defects. Wood

preservatives shall be applied to the entire drum. Ferrous parts used shall be treated with a

suitable rust preventive finish or coating to avoid rusting during transit or storage.

On the flange of the drum, necessary information such as project title, manufacturer's name, type

size, voltage grade of cable, length of cable in metres, drum no., cable code, BIS certification

mark, gross weight etc. shall be printed. An arrow shall be printed on the drum with suitable

instructions to show the direction of rotation of the drum.






PVC / Rubber end caps shall be supplied free of cost for each drum with a minimum of eight per

thousand metre length. In addition, ends of the cables shall be properly sealed with caps to avoid

ingress of water during transportation and storage.

specification for electrical equipment to be...

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