10.01.01. All the instrumentation cables i.e.
twisted and shielded multipair cables, compensating
cables, pre fabricated cables etc. shall be flame retardant low
smoke (FRLS) type. The cables shall be provided in non
returnable wooden drums. The drum length shall be 1000 m
(+/- 5%) up to & including 12 pairs and 500 m (+/- 5%)
above 12 pairs and B-type thermocouple cables.
10.01.02 Voltage grade of the instrumentation cables shall be 225 V (peak value).
10.01.03 All instrumentation cables covered in this specificationshall comply with VDE 0815, VDE 0207, part 4, part 5,part 6, VDE 0816, VDE 0472, SEN 4241475, ANSI MC 96.1,IS-8784, IS-10810,BS 5308-1, latest editions and its amendments
read along with this specification.
10.01.04 The conductor shall be of minimum 0.5 Sq.mm size, high
conductivity, multi-stranded copper tinned as per ASTM B33 & B8 for all types of instrumentation cables except the thermocouple extension cables which shall be 1.31 mm Sq. solid alloy type.
10.01.05 (a)The insulation of individual conductor shall be extruded PVC meeting the requirements of VDE 0207 part 4 compound Y I3. The outer sheath of instrumentation cables shall be extruded PVC (compound YM1)as per VDE 0207 part 5 and shall be of flame retardant low smoke (FRLS)type. The cable shall be provided with marking including manufacturer's name, insulation material, conductor size, No.of pairs, voltage ratings, type of cable etc.
Progressive sequential marking of the length of the cable at every one meter & progressive markings
to read FRLS at every 5 Mtrs. shall be provided on the outer sheath of all instrumentation cables. Pairs of
cables shall be identified by colour coding & colour banding.
Fillers in multiple conductor cables shall be flame retardant and moisture resistant. Cable accessories
such as harnessing components, markers, bedding, cable jointer, binding tape etc. shall also have flame
Fillers in multiple conductor cables shall be flame retardant and moisture resistant. Cable accessories
such as harnessing components, markers, bedding, cable jointer, binding tape etc. shall also have flame
(b)(i) Colour of outer Sheath of Cable -
The colour of outer sheath shall be sky blue so that C&I cables are easily distinguished from other cables.
10.01.06 All instrumentation cables shall be provided with overall shielding. However multipair cables carrying analogue signals shall be provided with individual pair shielding in addition to over all shielding. Shielding shall be of Aluminium-Mylar tape with 100% coverage and with at least 20% overlapping. The thickness of individual pair shield shall be 28 micron(Min)and that of over all shield shall be 55 microns(Min). Separate drain wires for individual pair shield(wherever applicable)as well as over all shield shall be provided.
Drain wire shall be of seven(7) strand 20 AWG(0.51 Sq.mm)tin coated copper conductor. Maximum lay of
individual twisted pair shall be 50 mm.
Bidder to ensure that individual core diameter shall be suitable for maxi-termi connection. Insulation thickness of individual core shall be between 0.28 and 0.35 mm for 0.5 Sq.mm cables and 0.35 to 0.45 mm for 1.31 Sq.mm cables.
10.01.07 The outer sheath of the instrumentation cables shall meet the following minimum requirements.
(i) An Oxygen index of not less than 29% and a Temp. index of not less than 250 Deg.C. as per ASTMD-2863.
(ii) Maximum acid gas generation by weight as per IEC-754-I shall not be more than 20%.
(iii) Smoke Density rating shall not be more than 60% during
Smoke Density Test as per ASTMD-2843. The results of
smoke density test shall be plotted on a curve
indicating light absorption vs time as per ASTMD-2843.
The average area under the curve(smoke density rating) shall not be more than 60%.
(iv)Complete cable assembly shall pass Swedish Chimney test as per SEN-4241475 and flammability test as per IEEE-383.
(v)Water immersion Test as per VDE-0815.The thickness of outer sheath shall be as per the
guidelines given in VDE-0816. Thickness of outer sheath
shall not be less than 1.8 mm in any case. Allowable
tolerance of over all diameter of the cables shall be
+/- 2 mm Max. over the declared value in technical data
sheets. The variation in diameter and the ovality at
any cross section shall not be more than 0.1 mm.
10.01.08 All instrumentation cables shall be suitable for continuous operation at 85 Deg.C. except for high
temp. resistant Teflon insulated cables which shall be suitable for continuous operation at 205 Deg.C. The
cables shall be suitable for laying in wet or dry locations in trays, conduits, ducts, trenches and under
ground buried installations.
10.01.09 The thermocouple extension cables shall be of single/ multi pair, twisted & shielded, PVC insulated, FRLS PVC sheathed and compatible for the type of thermocouples
employed. The material of conductor shall be as per ANSI MC-96.1. The material and requirements of
conductor insulation, shielding and outer sheath shall be as per Clause No.10.01.04 to 10.01.07.
10.01.10 a)Teflon Cable(205 Deg.C/600 V)
All cables near high temp. zone like burner front devices metal temp. thermocouples on main steam & turbine casing etc. shall be high temp. cables (205 Deg.C/600),which shall be terminated at a junction box in normal temp. zone. Thermocouple extension cables and silver plated copper conductor(ASTM-B298) cables for high temp. applications shall be with insulation of individual conductor and outer sheath of extruded FEP (i.e. Teflon)as per VDE-0207 part 6 and ASTMD -2116. The thickness of insulation shall be 0.5 mm nominal(i.e.0.4 mm Min.).These cables shall be single/ multipair, twisted & shielded.(At least 1 layer of heat resistant tap with 20% over lapping & 100% coverage). conform to IEC 60332.1 and IEC 60332.3.
10.01.11 Identification of the cores & pairs shall be done with suitable colour coding & band marking as well as by numbering of cores/ pairs as per VDE-0815. The details
of colour coding etc. shall be as approved by employer during detailed stage.
10.01.12 a)For analog signals individual pair shielding & over all
b)For binary signals only over all shielding of instrumentation cable.
10.01.13 Cable Parameters at 20 Deg.C
a) Mutual capacitance (Max) at 0.8 KHz
(i) 120 nF/KM for type F & I,
(ii)100 nF/KM for G Type and
(iii)200 nF/KM for compensating cable.
b) Max. Conductor resistance shall be 73.4 ohm/KM loop.
c) Insulation Resistance(Min) shall be 100 M ohm/ KM.
d) Cross talk(Min)fig at 0.8 KHz shall be 60 db.
e) Characteristic impedance (Max) at 1 KHz shall be 320 ohm.
f) Attenuation fig at 1 KHz(Max)shall be 1.2 db/KM & 0.8 db/
KM for `F’ Type.
10.01.14 Description of various type of Cables
i) Type "A" Size 1.31 Sq.mm -
Two pair shielded and twisted pair T/C Extn.cable, ANSI type KX, solid alloy conductor.
ii) Type "B" Size 1.31 Sq.mm -
Two pair shielded and twisted T/C Extn.cable, ANSI type SX, solid alloy conductor.
iii) Type "C" Size 1.31 Sq.mm -
Two pair shielded and twisted heat resistant teflon Insulation & outer sheath T/C Extn.cable, ANSI type KX, solid alloy conductor.
iv) Type "E" Size 0.5 Sq.mm -
Two individual pair and over all shielded twisted pair instrumentation cable for both analog and digital
signal to be used from field mounted instruments to local junction box.
v) Type "F" Size 0.5 Sq.mm
Multipair individual pair and over all shielded twisted pair instrumentation cable (4/8/12/36/48 pair) for
analog signals with stranded copper conductor.
vi) Type "G" Size 0.5 Sq.mm
Multipair over all shielded & twisted pair instrumentation cable (4/8/12 24/48/64 pair) for binary
signals with stranded copper conductor.
vii) Type "I" Size 0.5 Sq.mm/1.5 Sq.mm
Type F cable/type G cable with heat resistant teflon insulation & outer sheath for high temp.(0-205 Deg.C) application.
10.01.15 All instrument cables shall be Galvanized steel wire armoured type conforming to Indian Standard (IS-3975).
10.01.16 All cables shall be Anti rodent and antitermite type.
10.01.17 a)Cables for relay based system shall be of 1.5/2.5 Sq.mm conductor size.
b)1.5 or 2.5 Sq.mm copper conductor size for power supply cable for solenoid.
c)All contacts of process actuated switches and both the elements of T/C & RTD shall be wired up to junction box.
d)All CAT 5/6,UTP , prefab cable shall be FRLS.
e)all CAT 5/6 cable shall be conform to TIA/EIA 568.
10.02.00 Instrumentation Cable Interconnection and Termination Philosophy.
10.02.01 Plug in Connector
a) Valve & Damper electric drive (internal junction boxes).
b) Transmitter, E/P Converter ,process actuated switches.( MIL standard -5015)
10.02.02 Cage Clamp Type
a) Marshalling/local/system Cubicle
b) Junction Box
c) C J C Box
10.02.03 Prefab Cable
a) UCP Mounted Instrument
b) Annunciation System
c) System cabinet
10.02.04 Manufacturer's Standard
a) P A System
b) Flame Scanner etc.
e) PC, Printer
10.03.00 .Internal Panels/ Cabinets/ System Cabinets Wiring
10.03.01. The internal wiring and prefab cable in factory prewired electronic system Cabinets may be installed according to bidder standard as per wire size, insulation and method of termination on internal equipment except that insulation for all wiring, power supply wiring inter connecting cable and prefab cable between devices shall pass the following Test.
a) IEEE 383/1974, Flammability Test
b) When tested under UITPP Test method or ASTM 2893/77
light transmittance of 80%.
c) When test under IEC 60754-1 maximum acid gas generation
shall be 2% by weight.
d) Oxygen index not less than 30 as per ASTM D 2863.
e) Degree of acidity of gases – IEC 60754.2 (PH >4.3)
10.03.02 Wiring to door mounted devices shall be done by 19 strand copper wire provided with adequate loop lengths of hinge wire so that multiple door opening shall not cause fatigue breaking of the conductor.
10.03.03 All internal wires shall be provided with tag & identification Nos. etched on tightly fitted ferules at both ends in Employer's approved format. All wires directly connected to trip devices shall be distinguished by one additional red colour ferrule.
10.03.04 All external connection shall be made with one wire per termination point. Wires shall not be tapped or spliced between terminal points.
10.03.05 All floor slots of desk/panels/cabinets used for cable entrance shall be provided with removable gasket gland plates and fire proof sealing material to prevent dust entry and propagation of fire. Split type grommets shall be used for prefabricated cables.
10.03.06 All the special tools as may be required for solder less connections shall be provided by bidder.
10.03.07 Wire sizes to be utilized for internal wiring(cabinet/panel/LIE etc) -
i) Current(4-20 mA) : 0.5 Sq.mm Low Voltage Signals(48 V)
ii) Ammeter/ Voltmeter Circuit, : 1.5 Sq.mm control switches etc.for Electrical System.
iii) Power supply and internal : 2.5 Sq.mm Min. illumination. shall be as per
load requirement & cable voltage drop : 2%of supply voltage
10.04.00 Junction Boxes (Field Mounted)
i) Design as per NEC-370 Article 18,19 & 20
ii) 3 mm thick(min) made of Aluminum(LM 6;BS-1490)
iii) Protection Class - IP-65/ NEMA4 or better
iv) With 20% spare terminals The terminal Block shall be screw less cage clamps type. All the TBs used shall be 6.6polymide to withstand corrosion and the metallic portion shall be coated against rust / corrosion.
v) Lock with common key and hinge door.
vi) Double compression type cable gland shall be provided as per BS.
vii) Separate J B for
(i)Binary & Analog signals.
(ii)Different voltage level Signals.
viii)Suitable for mounting on walls, columns, structures etc. The brackets, bolts, nuts, screws, glands and lugs
required for erection shall be of brass/6.6 polymide, included in Bidders scope of supply. A M6 earthing stud shall be provided.
ix) Gasket (Normal)- Neoprene ,
High Temp. Zone (near burner, Turbine area)- Silicone.
x)In each JB ,a DC Voltmeter shall be provided .
xi)No of ways -12/24/36/64/96/128/256 with 20% spare terminals
xii) Separate Junction Boxes shall be provided for intrinsically safe instruments/equipments as per NEC.
i) All rigid conduits, couplings and elbows shall be hot dipped galvanized rigid mild steel in accordance with IS: 9537 Part-I (1980) and Part-II (1981). The conduit interior and exterior surfaces shall have continuous zinc coating with an overcoat of transparent enamel lacker or zinc chromate. Flexible conduit shall be heat resistant lead coated steel, water leak proof, fire and rust proof. The temperature rating of flexible conduit shall be suitable for actual application. Flexible Metal Conduit (Type FMC) is constructed with an interlocked corrosion-resistant steel and is manufactured in accordance with UL 1 and NEC Article 348, which specifies strip thickness, splices, convolutions, interior surfaces, conduit diameters (internal and external) and the quality requirements and zinc coated steel.
Bidder shall provide 25mm & 50 mm rigid conduit and 18mm & 36 mm flexible conduit as per requirement.
ii) all unarmored communication cable(UTP,CAT5/6),unshielded cable ,optical cable, coaxial cable etc shall, be installed in conduit .
iii)The Bidder shall install conduits according to the routing as approved by owner .
10.06.00 Optical cablea) Optic Fiber cable shall be 4/8/12 core, polymer coated corrugated steel taped armoured, fully water blocked with
dielectric central member for outdoor/indoor application so as to prevent any physical damage. The cable shall have multiple single-mode or multi mode fibers on as required basis so as to avoid the usage of any repeaters. The core and cladding diameter shall be 9 +/- 1 micrometer and 125 +/- 1 micrometer respectively. The outer sheath shall have Flame Retardant, UV resistant properties and are to be identified with the manufacturer’s name, year of manufacturer, progressive automatic sequential on-line marking of length in meters at every meter on outer sheath.
b) The cable core shall have suitable characteristics and strengthening for prevention of damage during pulling viz. Steel central member, Loose buffer tube design, 4 fibers per buffer tube (minimum), Interstices and buffer tubes duly filled with Thixotropic jelly etc. The cable shall be suitable for a maximum tensile force of 2000 N during installation, and once installed, a tensile force of 1000 N minimum. The compressive strength of cable shall be 3000 N minimum& crush resistance 4000 N minimum. The allowable bending radius for the cable shall be 20 times the outer diameter.
C) The operating temperature range shall be 0 deg. C to 70 deg.C
d) Optical cable shall be conform to
i) IEC 60794.
ii)low smoke(IEC 1034 -light transmittance of 80%).
iii) halogen free(IEC 754: 1&2- maximum acid gas generation shall be 2% by weight and PH >4.3).
iv) fire & flame retarded (IEC 331,IEEE 383).
v) rodent resistant .
vi)Crush Resistant (EIA -455-41).
vii)Impact Resistant (EIA -455-25).
e)Bidder shall submit Type test report for review ,conform to IEC 60794, IEEE 383, IEC 754: 1 & 2,IEC 331 ,IEEE 1034 and EIA standard.
f) Color codes shall be as per EIA/TIA 598-A.
10.06.01 Co-axial cable shall be low smoke (ASTM- E 662), flame retarded (IEEE 383) and halogen free(IEC 754: 1 & 2), MIL C-17 G.
VENDER (FIBER OPTICS)
1.AKSH FIBER( www.aksoptifibre.com )
2.BIRLA ERICTION (www.birlaericssion.com )
3.FINOLEX (www.finolex.com )
5.OPTICAL CABLE CORPORATION www.occfiber.com
10.08.00INSTRUMENTATION CABLE INSTALLATION AND ROUTING10.01.00 All cables assigned to a particular duct/conduit shall be grouped and pulled in simultaneously using cable grips and suitable lubricants. Cables removed from one duct/conduit shall not be reused without approval of Employer.
10.02.00 Cables shall be segregated as per IEEE Std.-422 and IEEE 524 (1992) In vertically stacked trays, the higher voltage cable shall be in higher position and instrumentation cable shall be in bottom tier of the tray stack. The distance between instrumentation cables and those of other system shall be as follows:
From 11 kV/6.6 kV/3.3 kV tray system - 914 mm
From 415V tray system - 610 mm
From control cable tray system - 305 mm
10.03.00 Cables shall terminate in the enclosure through cable glands. All cable glands shall be properly gasketed. Sealing (to prevent ingress of dust entry and propagation of fire) shall be provided for all floor slots used for cable entrance. Compression cable glands (double for armoured and single for other cables) shall be provided.
10.04.00 All cables shall be identified by tag. Nos. provided in Employer's approved format at both the ends as well as at an interval of 5 meters.
10.05.00 Line voltage drop due to high resistance splices, terminal contacts, insulation resistance at terminal block, very long transmission line etc. shall be reduced as far as practicable.
10.06.00 The cables emanating from redundant equipment/devices shall be routed through different paths. The above segregation of cables & wiring for redundant equipments/devices shall be in accordance with IEEE-Std-422.
10.07.00Maximum of 2 wires shall be terminated per terminal. Wiring raceways, strapes shall be flame retardant. All wiring shall be ferruled.(printed Partex type ferrule shall be used)Wires carrying power and signal wires shall be routed in separate raceways. Accessories like MCB, cable support fuses, etc. shall be supplied.
10.08.02 .Cable GlandsCables shall be terminated using double compression type cable glands. Cable glands shall conform to BS: 6121 and IP67 and be of robust construction capable of clamping cable and armoured cable(for armoured cables) firmly without injury to insulation. Cable glands shall be made of heavy duty brass machine finished and nickel chrome plated. Thickness of plating shall not be less than 10 micron. All washers and hardware shall be made of brass with nickel chrome plating Rubber components shall be of neoprene and of tested quality.
10.08.03 Cable Trays
(i) NEMA – VE1 and VE2
(ii) IEC- 61537
(iii) NEC 392
b)Cable trays, fittings and accessories shall be fabricated out of rolled mild steel sheets free from flaws such as laminations, rolling marks, pitting etc. Cable tray shall conform to as per NEMA VE1 or relevant Indian standard.
c)Installation shall be as per NEMA- VE2.
d)The cable sub-trays and the supporting system, to be generally used between Local/Group JBs and the main cable trays and the same shall be furnished and installed by the Contractor. It is the assembly of sections and associated fittings forming a rigid structural system used to support the cable from the equipment or instrument enclosure up to the main cable trays (trunk route).
e) The covers on the cable sub-trays shall be used for protection of cables in areas where damage may occur from falling objects, welding spark, corrosive environment, etc. & shall be electrically continuous and solidly grounded. The cable trays shall not have sharp edges, burrs or projections injurious to the insulation or outer sheath of cable.
Ref : www.cabletrays.com
10.09.00 Spare core in cable
Bidder shall provide at least 10% spare core or minimum one pair and 100% spare core in optical cable.
10.10.00 All wiring shall be routed as per NFPA – 70 and NEC.
1011.00.CABLE LAYING AND ACCESSORIES
10.11.01CABLE LAYING1 Cables shall be laid strictly in line with cable schedule.
2 Identification tags for cables.
Indelible tags to be provided at all terminations, on both sides of wall or
floor crossing, on each conduit/duct/pipe entry/exit, and at every 20 m in cable trench/tray.
3 Cable tray numbering and marking.To be provided at every 10m and at each end of cable way & branch connection.
4 Joints for less than 250 Meters run of cable shall not be permitted.
5 Buried cable protection With concrete slabs; Route markers at every 20 Meters along the route & at every bend.
6 Road Crossings Cables to pass through buried high density PE pipes encased in PCC. At least 300 mm clearance shall be provided between
- HT power & LT power cables,
- LT power & LT control/instrumentation cables, Spacing between cables of same voltage grade shall be in accordance with the derating criteria adopted for cable sizing.
7 Segregation (physical isolation to prevent fire jumping)
a, All cable associated with the unit shall be segregated from cables of other Units.
b, Interplant cables of station auxiliaries and unit critical drives shall be
segregated in such a way that not more than half of the drives are lost
in case of single incident of fire.
8 Cable clamping All cables laid on trays shall be neatly dressed up & suitably clamped/tied to the tray. For cables in trefoil formation, trefoil clamps shall be provided.
9 Optical fiber cables inside conduit shall be laid on cable trays wherever
available and feasible. In areas where the same are required to be buried,
the same shall be buried in separate trench approx.1.6 meter depth, to be
laid in 2” GI/rodent proof HDPE conduits covered with sand, brick and soil
along the pipe line route; While crossing roads - to be laid in GI/rodent proof HDPE conduits with sand filling at bottom and sand, soil filling at top with cement concrete;While crossing canals/river- to be laid in GI/rodent proof HDPE conduits within hume pipe.
9.02.00 Bidder shall supply and install all cable accessories and fittings like Light Interface Units, Surge suppressors, Opto isolators, Interface Converters, Fibre Optic Card Cage, Fibre Optic Line Driver, Repeater / Modem (for Optical Fibre Cables), cable glands, grommets, lugs, termination kits etc. on as required basis.
10.11.02 Bidder shall furnish two completely new sets of cable termination kits like Crimping tools, etc., which are required for maintenance of the system as per the type of termination used.
10.11.03.Cables, which terminate in cabinets of draw out sections shall have sufficient cable coiled in the bottom of the cabinet to permit full withdrawal of draw out sections without disconnecting the cables. When prefabricated cables with factory connectors on both ends are longer than required, the excess cable shall be coiled in the bottom of one or both termination cabinets.
10.11.04.No splices shall be made in conductors for instrument and control circuits except where required at connections to devices equipped with factory installed pigtails.Such splices shall be made only in approved splicing boxes of fitting with removable cover. The splices shall be made with sufficient slack left in the wires to permit withdrawal of the splice from the splicing box for ease of future disconnection of the
splices. All exposed conductor or connector surfaces shall be covered with a
minimum of three half-lapped layers of all weather vinyl plastic electrical tape. Taping shall extend a minimum of two cable diameters over the cable jacket and a similar distance over the other insulation or connections requiring insulation.
1011.05.The Bidder shall be responsible for proper grounding of all equipment under C&I package. Further, proper termination of cable shields shall be verified and the grounding of the same shall be coordinated so as to achieve grounding of all instrumentation cable shields at same potential. This shall be completed prior to system tests. All the cables etc. required for grounding of all equipments supplied under this package are to be supplied by the Bidder.
10.11.06.The Contractor shall take full care while laying / installing cables as recommended by cable manufacturers regarding pulling tensions and cable bends. Cables damaged in any way during installation shall be replaced at the expense of the bidder.
INSTRUMENTATION CABLE VENDERS
1.KERPEN CABLE ,GERMANY. www.leon-kerpen.com)
2.LAPP CABLES, GERMANY. ( www.lappusa.com )
3.HABIA CABLE,SWEEDEN.( www.habia.se )
4.THERMO ELECTRIC . www.thermo-electric.nl
5.BELDEN, USA www.belden.com
6.NORTHWIRE INC,USA (www.northwire.com )
7.GENERAL CABLE USA . www.generalcable.com
8.CABLE USA LLC, www.cableusa.ccVENDERS(INDIA):
1.DELTON CABLES,FARIDABAD . ( www.deltoncables.com )
2.PARAMOUNT CABLES, ALWAR ( www.paramountcables.com )
3.UNIVERSAL CABLE,SATNA.( www.unistar.co.in )
4.CORDS CABLE ( http://www.cordscable.com/)
5.POLYCAB CABLE ,DAMAN.
6.RELIANCE , BANGALORE
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