I N T R O D U C T I O N

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George Cannon
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2 I N T R O D U C T I O N GEMSCAB are being manufactured by the people who have been associated with the industry for over years and understand the requirements their valued customers. The company took up the manufacture Poly Vinyl Chloride isnulated power s, control s, industrial wirirng s, flexible s, mining s, and instrumentation paired s etc. in the year 187. After playing an excellent role in the manufacture L.T. PVC s the company has been successful in developing Fire Retardant Low Smoke (F.R.L.S.) Heat Resistant PVC s suitable for 85 0 C & 5 0 C continous operation and other customer built s through its well equipped Research and Development facilities & experienced team. The factory is equipped with the most modern production, and testing facilities to make the best s capable satisfying the requirements quality. Properties and Advantages GEMSCAB CABLES 1. GEMSCAB s are excellent moisture resistant, and high dielectric stength even if the s are immersed in water. 2. GEMSCAB s have high short circuit safety & overload capacity. 3. GEMSCAB s have high mechanical strength, suitable for laying on slops and vertical shafts. 5. GEMSCAB s are high resistant to most chemicals, acids, bases and oils.. GEMSCAB s are flame retardant. 7. GEMSCAB cabels have a smooth outer surface resulting in a neat appearance when installed. 8. GEMSCAB s have a long working life. General Construction Conductor The conductors power s are normally made from electrical purity aluminium and for control s high conductivity annealed copper. All conductors confirm to IS: Aluminium conductors upto mm 2 are solid circular in cross section and above mm 2 the conductors are stranded. In case single core s the conductors are circular, for two core s they are D shape above mm 2 and for 3 core and core s the conductors are sector shaped above mm 2. Stranded conductors are also give below 1 mm 2 if required for any specific application field. Insulation The conductors are insulated with the high quality PVC compound confirming to IS: Special compounds are continously developed to meet customers requirements. Manufacturing Programme Cable Type Normal Manufacturing Range Power 1.1 K.V. Single core upto 00 mm 2 Multi core upto 00 mm 2 Power 3.3 K.V. to 33 K.V. Single core upto 00 mm 2 3 core upto mm 2 Control 1.1 K.V. Upto 1 cores mm 2 and mm 2 Mining 1.1 K.V. & 3.3 K.V. Multi core upto mm 2 Instrumentation Cabels Upto pairs Flexible Wires and As per special requirements 2

3 Core Identification Colour Scheme Core are identified by colour PVC insulation given as under: 1 Core Red, Black, Yellow or Blue. 2 Core Red and Black. 3 Core Red, Yellow and Blue. Core Red, Yellow, Blue and Black. (For 3½ Core Reduced neutral core is Black) 5 Core Red, Yellow, Blue, Black and Grey. Core and above Two adjacent cores (counting & direction) in each layer, Blue and Yellow, remaining cores Grey. Core numbering and different colours are also given for control & paired s. Laying up cores In twin, three and multicore s the cores are laid up together with a suitable lay, the outer most layer is laid up in right hand and successive layers with opposite lay. The interstices are filled with nonhygroscopic material. Inner Sheath (Common Covering) For all s having two or more cores, a common covering is applied over the laid up cores either by extrusion PVC compound or wrapping plastic or proed tapes. Single core s do not have inner sheath. Armouring Armouring is applied over the inner sheath. Where the calculated diameter below armouring does not exceed 13 mm, the armour consists galvanized round steel wires, above the size; normally the armour is galvanized flat steel strips. Armouring GEMSCAB Mining s consists galvanized round steel wires / strips, but a few tinned copper wires / strips are also provided to meet the conductance requirements armouring. Outer Sheath The tough outer sheath is applied by extrusion. It is applied: 1. Over insulation in case single core unarmoured s. 2. Over inner sheath in case multi core unarmoured s. 3. Over armouring case armoured s. The colour outer sheath is normally black for best resistance. However, other colour can also be given as required by any customer. The manufacturers trade name GEMSCAB alongwith voltage grade are embossed on the outer sheath and in case L.T. s the world ELECTRIC and in case mining s, the word MINING is added in the embossing script. Properties PVC (Electrical & Physical) Dielectric constant 5 to 8 Dielectric strength Volume Resistivity at 27 0 C 30 KV / mm (Min.) 13 to 1 ohmcm Specific gravity 1.3 to Tensile strength at break Elongation at break Continuous operating Temperature for s Max. overload temperature Max. short circuit temperature Cable Code 1 N / mm 2 (Min.) 1% (Min.) 0 C for normal PVC 85 0 C for HR PVC for normal PVC 0 C for HR PVC 5 0 C 10 0 C The following codes are used for designation s: A Y W F WW FF Y CE Aluminium conductor (when type designation doesn t contain A in the beginning then is with copper conductor.) At first or second place in type desingation, it stands for PVC insulation. Steel round wire armour. Steel strip armour. Steel double round wire armour. Steel double flat strip armour. When last in type designation it stands for PVC outer Sheath. Individual core screening. Conductor Types re Circular, solid conductor. rm Circular stranded conductor. rm / v Circular stranded compacted conductor. sm Sector, shaped, stranded conductor. 3

4 GEMSCAB Quality Control System 1. Test at Raw Material Stage GEMSCAB PVC insulated s are manfuactured from quality raw materials, which are tested in our laboratory strictly according to our works requirements. For PVC insulated s, the raw materials and tests generally conducted are as under: (i) Aluminium / Copper wire Conductor resistance, wire diameter, tensile strength, annealing and wrapping test. (ii) PVC Compound Density, tensile strength, elongation at break, volume resistivity and shrinkage test. (iii) Steel strip / Wire Dimensions, tensile strength, elongation at break, torsion, resistivity and zinc coating test. 2. Production Shop Preventive Test i.e. Process Inspection The process control tests are carried out at every stage manufacture for checking the adequate manufacturing process, and taking necessary steps to remove any defects. The following are the process inspections carried out by us for PVC s. (i) Conductor stranding a) Dimensions b) Surface and shape conductor c) Lay and direction lay d) D.C. resistance e) No. wires in each conductor (ii) Insulation a) Dimension cores b) insulation c) Surface d) Spark test, shrinkage test and I.R. test (iii) Laying up a) Sequence cores b) Direction laying up and lay c) Circularity d) Diameter over laid up cores e) Application filler in the interstices (iv) Inner Sheath a) Surface b) Concentricity c) d) Diameter over inner sheath (v) Armouring a) Lay and direction lay armouring wire / strips b) No. wires / strips c) Uniformity application d) Diameter over armouring e) Dimension wires / strips (vi) Outer Sheath a) b) Concentricity c) Diameter over sheath d) Surface e) Embossing with requisite information on outer sheath 3. Finished Cable Test We have a well equipped arconditioned laboratory with state the ultravoilet Rediation Testing, accelerated water absorption testing & dielectric strength retention testing instruments. All routine, acceptance and type tests are conducted as per relevant specifications and testing schemes i.e. IS:155 (PartI) 18 amended upto date, and IS: 10 with latest amendments. FRLS GEMSCAB FRLS PVC CABLES are the result keeping pace with the latest trends in technological innovations in the field. The specially formulated compounds meet the stringent requirements international specifications. GEMSCAB FRLS range covers various specific requirements any customer be it oxygen index or corrosive gas generation or light absorbance. A typical GEMSCAB FRLS PVC sheathed shall give following results. 1. Oxygen Index 2% min. 2. Temperature Index 0 0 C min. 3. Smoke Density Rating 0% max.. Acid Gas Emission 20% max. 5. Flammability Test as per: i) IEC 332 I ii) IEC 332 III iii) IEEE 383 iv) SS 2 175

5 FLOW CHART FOR MANUFACTURING PROCESSES & QUALITY CONTROL CHECKS FOR CABLES TO IS:155 (PART1) 5

6 CONTINUOUS CURRENT RATINGS The current ratings given are based on the normal conditions installation installation described below: Maximum conductor Temperature For PVC 0 C For HR PVC 85 0 C Ambient Air Temperature 0 0 C Ground Temperature 30 0 C Depth laying 75 cm (1.1 K.V.) (for s laid direct in ground) 0 cm (3.3 K.V.) Thermal Resistivity Soil 1 0 C cm / watt Thermal Resistivity PVC 0 C cm / watt Type Installation Twin and multi core Cable laid singly 3 single core s laid in trefoil touching formation In case control s all cores are assumed to be carrying full load current. For other conditions, the corresponding rating, factors are to be applied. RATING FACTORS In actual practice the conditions installations may be different than normal conditions. Therefore, to determine the continous current rating for the actual operating conditions, the tabulated ratings should be multiplied by the appropriate rating factors given in Table 1 to 11. Table 1 Rating factors for grouping single core s laid direct in Ground in horizontal formation (three s in trefoil trouching) Number circuits in Group Spacing Touching 15 cm 30 cm 5 cm 0 cm Table 2 Rating factors for variation in Ground Temperature for s laid direct in Ground and Duct Temperature 0 C Rating factor for PVC for HR PVC

7 RATING FACTORS Table 3 Rating factors for multi core laid on racks in Air (with touching) Arrangement Number Racks Number s per Rack Table Rating factors for variation in ambient Air Temperature Temperature ( 0 C) Rating factor for PVC for HR PVC Table 5 Rating factors for variation in depth laying in Ground Depth laying (mm) and above Upto Sq. mm Above Sq. mm. and upto Sq. mm Above Sq. mm Table Rating factors for Grouping Twin and multicore s laid direct in Ground Number circuits in Group Spacing when laid in horizontal formation Spacing when laid in tier formation Touching 15 cm 30 cm 5 cm 0 cm Touching 15 cm 30 cm 5 cm 0 cm

8 RATING FACTORS Table 7 Rating factors for variation in depth laying (Twin and multi core s laid in single way ducts) Depth laying (mm) Rating factor or more Table 8 Rating factors for variation in Thermal resistivity Soil (Twin and multi core s) Nominal area conductor (Sq. mm) Thermal Resistivity Soil in 0 C cm / watt (Cable laid direct in the Ground) Thermal Resistivity Soil in 0 C cm / watt (Cable laid in single way duct) Table Rating factors for Grouping twin and multi core s laid in ducts or pipes Number Ducts in Group Spacing when laid in horizontal fomation Spacing when laid in tier fomation Touching 30 cm 5 cm 0 cm Touching 30 cm 5 cm

9 RATING FACTORS Table Rating factors for variation in Thermal resistivity Soil (3 Single core s) Nominal area conductor (Sq. mm) Thermal Resistivity Soil in 0 C cm / watt (Cable laid direct in the Ground in Trefoil touching) Thermal Resistivity Soil in 0 C cm / watt (Cable laid in Trefoill duct) Table 11 Rating factors for multi core laid on racks in Air (with spacing between s equal to diameter the ) Arrangement Number Racks Number s per Rack

10 BENDING RADIUS The following minimum bending radius should be observed for GEMSCAB CABLES in order that the s, specially insulation, may not get damaged in installation. Single core GEMSCAB 15 D Multi core GEMSCAB 1.1 K.V. 12 D Multi core GEMSCAB 3.3 K.V. 15 D where D is the overall diameter. RECOMMENDED PULLING FORCE a) When conductor pulled by pulling eye: (i) Aluminium conductor (Newton) 30 Total conductor area in Sq. mm. (ii) Copper conductor (Newton) Total conductor area in Sq. mm. b) When pulled with stocking: (i) Unarmoured s 1.1 K.V. (Newton) 5 D 2 (ii) Armoured s 1.1 K.V. (Newton) D 2 where D is overall diameter. SHORT CIRCUIT MVA CAPACITY Short circuit MVA Capacity s may be worked out with the following formula: MVA Capacity = 3 E I k where : E Phase to phase voltage in K.V. I k Short circuit current in K.A. HR PVC Using HR PVC, s can be operated at 85 0 C continuous conductor temperature. Hence with same conductor size 118% more current can be drawn.

11 DIMENSIONS & WEIGHTS 1.1 KV Single Core PVC insulated & sheathed unarmoured & armoured with Aluminium Conductor conforming to IS:155 / Part 1 / 188 Nominal area conductor Nominal thickness insulation UNARMOURED outer sheath Overall dia Weight insulation Diameter round wire Dimension flat strip ARMOURED outer sheath (Minimum) Overall dia Weight Sq mm mm mm mm (Kg / Km) mm mm mm mm mm (Kg / Km)

12 DIMENSIONS & WEIGHTS 1.1 KV Two Core PVC insulated & sheathed unarmoured & armoured with Aluminium Conductor conforming to IS:155 / Part 1 / 188 Nominal area conductor insulation inner sheath (Minimum) outer sheath UNARMOURED Overall dia Weight Diameter round wire Dimension flat strip ARMOURED outer sheath (Minimum) Overall dia Weight Sq mm mm mm mm mm (Kg / Km) mm mm mm mm (Kg / Km)

13 DIMENSIONS & WEIGHTS 1.1 KV Three Core PVC insulated & sheathed unarmoured & armoured with Aluminium Conductor conforming to IS:155 / Part 1 / 188 Nominal area conductor insulation inner sheath (Minimum) outer sheath UNARMOURED Overall dia Weight Diameter round wire Dimension flat strip ARMOURED outer sheath (Minimum) Overall dia Weight Sq mm mm mm mm mm (Kg / Km) mm mm mm mm (Kg / Km)

14 DIMENSIONS & WEIGHTS 1.1 KV Three and Half Core PVC insulated & sheathed unarmoured & armoured with Aluminium Conductor conforming to IS:155 / Part 1 / 188 Nominal area conductor insulation Main Netural Main Neutral inner sheath (Minimum) UNARMOURED outer sheath Overall dia Weight Diameter flat strip ARMOURED outer sheath (Minimum) Overall dia Weight Sq mm Sq mm mm mm mm mm mm (Kg / Km) mm mm mm (Kg / Km)

15 DIMENSIONS & WEIGHTS 1.1 KV Four Core PVC insulated & sheathed unarmoured & armoured with Aluminium Conductor conforming to IS:155 / Part 1 / 188 Nominal area conductor insulation inner sheath (Minimum) outer sheath UNARMOURED Overall dia Weight Diameter round wire Dimension flat strip ARMOURED outer sheath (Minimum) Overall dia Weight Sq mm mm mm mm mm (Kg / Km) mm mm mm mm (Kg / Km)

16 DIMENSIONS & WEIGHTS 1.1 KV Sq mm (Solid) Multicore PVC insulated & sheathed unarmoured & armoured Copper Control s conforming to IS:155 / Part 1 / 188 Nominal cores insulation inner sheath (Minimum) outer sheath UNARMOURED Overall dia Weight Diameter round wire Dimension flat strip ARMOURED outer sheath (Minimum) Overall dia Weight (Nos.) mm mm mm mm (Kg / Km) mm mm mm mm (Kg / Km)

17 DIMENSIONS & WEIGHTS 1.1 KV Sq mm (Solid) Multicore PVC insulated & sheathed unarmoured & armoured Copper Control s conforming to IS:155 / Part 1 / 188 Nominal cores insulation inner sheath outer sheath (Minimum) UNARMOURED Overall dia Weight Diameter round wire Dimension flat strip ARMOURED outer sheath (Minimum) Overall dia Weight (Nos.) mm mm mm mm (Kg / Km) mm mm mm mm (Kg / Km)

18 CURRENT RATINGS Current ratings for PVC insulated Aluminium Conductor 1.1 KV grade s Nominal Area conductor Single Core Two in Ground Three Two Core Three, Three and a half & Four Core Single Core Two in Air Three Two Core Three, Three and a half & Four Core AC DC AC AC AC AC DC AC AC AC Sq. mm (Amps) (Amps) (Amps) (Amps) (Amps) (Amps) (Amps) (Amps) (Amps) (Amps)

19 CURRENT RATINGS Current Ratings for HR PVC insulated Aluminium Conductor 1.1 KV grade s Nominal Area conductor Single Core Two in Ground Three Two Core Three, Three and a half & Four Core Single Core Two in Air Three Two Core Three, Three and a half & Four Core AC DC AC AC AC AC DC AC AC AC Sq. mm (Amps) (Amps) (Amps) (Amps) (Amps) (Amps) (Amps) (Amps) (Amps) (Amps)

20 CURRENT RATINGS Current ratings for PVC insulated Copper Conductor 1.1 KV grade s Nominal cores Nominal area conductor Sq mm Nominal area conductor Sq mm In ground In air In ground In air (Nos.) (Amps) (Amps) (Amps) (Amps)

21 CURRENT RATINGS Current ratings for PVC insulated Copper Conductor 1.1 KV grade s Nominal area conductor Single core* s in ground Two core s Three, three and half & four core s Single core s in air Two core s Three, Three and half & four core s (Nos.) (Amps) (Amps) (Amps) (Amps) (Amps) (Amps) *Three Single core s laid in trefoil formation. Note: The General construction GEMSCAB s with Copper conductors shall be same as that GEMSCAB s with Aluminium conductors except for the net weight which shall be furnished on request. 21

22 CONDUCTOR RESISTANCE Nominal area conductor Max. D.C. Resistance at 20 0 C Aluminium Approx A.C. Resistance at operating Temp. 0 C Max. D.C. Resistance at 20 0 C Plain Copper Approx A.C. Resistance at operating Temp. 0 C (Sq mm) Ohm / km Ohm / km Ohm / km Ohm / km

23 REACTANCE Approximate Reactance at H z (Ohms / Km) 1.1 KV PVC and HR PVC Nominal area conductor Single core PVC and HR PVC s (Sq mm) Unarmoured Armoured* Multicore *Wire armoured. 23

24 CAPACITANCE Approximate Capacitance (Micro Farads / Km) 1.1 KV PVC and HR PVC Nominal area cross section Single core PVC and HR PVC s (Sq mm) Unarmoured Armoured Twin & Multicore

25 SHORT CIRCUIT RATINGS Short circuit rating 1.1 KV grade s (Kilo Amps) Nominal Area conductor PVC HR PVC (Sq mm) Copper Aluminium Copper Aluminium Max. Conductor temperature before short circuit: for normal PVC 0 C for HR PVC 85 0 C 2. Max. Conductor temperature during short circuit 10 0 C. 3. Max. duration short circuit 1 second. Formula for calculating the short circuit rating for other duration. Ish : KA Where Ish = Short circuit current in KA t K = Constant (.07 for Aluminium & 0.0 for copper) A = Area cross section in Sq.mm. t = Duration short circuit in seconds (The above formula is valid for t from 0.2 to 5 seconds)

26 FORMULA FOR CALCULATING VOLTAGE DROP IN A BALANCED 3 PHASE AC DISTRIBUTION SYSTEM HZ Voltage drop (rms) per KM per Phase (Volts) = 3 K T K AC [Max. continous curent rating (Amps)] [D.C. Resistance per phase per KM (Ohms/Km)] Where K T = 1 + a (Tc To) ; a = for Copper a = 0.00 for Aluminium Tc = Max. conductor temperature ( 0 C) To = 20 0 C standard temperature. and K AC factor for converting DC resistance to AC resistance. Approximate values K AC for 10 V are given below: Nominal Conductor Area (mm 2 ) Copper Conductor Aluminium Conductor to

27 RECOMMENDED GEMSCAB CABLE SIZES For Motors with StartDelta Starter For Motors with DOL Starters 3 Phase 15 V HP 15 V Hz KW Approx. full load current in Amps Phase Current in Amps Typical Cable size Aluminium Supply side Motor side Typical Cable Size Copper Supply side Motor side 3 Phase 15 V, Hz HP 15 V, Hz KW Approx full load current in Amps Typical Cable Size Aluminium (sq mm) Copper (Sq mm) / / / / / / / / / / / / / / 0.75 / / / / / / / / / / / / / / / / / / 0 20 / / / 27

28 GEMSCAB INDUSTRIES LTD. WORKS: SP112/L, PhaseIV RIICO Industrial Area, Bhiwadi Distt. ALWAR (Rajasthan) Ph: (013) , MARKETING OFFICE: 0, Rajasthan Udyog Nagar, G.T. Karnal Road, Delhi1 033 Ph: (011) 278, 2717, 271 Fax: (011) Mumbai: 03, Tulsiani Chambers 212, Nariman Point, Mumbai Ph: (022) 22835, Mobile: Fax: (022) gemscabmum@vsnl.net BRANCH OFFICES: Chennai: 51, Moore Street, Facing Erabalu Chetty Street, Madras Ph: Mobile: Kolkata: 2, Ganesh Chandra Avenue, Kolkata0 013 Ph: (033) , Mobile: Fax: (033) Representatives: Bangalore, Hyderabad, Chandigarh, Kanpur, Tatanagar, Jodhpur, Jaipur Website: 28 adcircle/2k/jan0

Introduction. for over a period 4 decades now. Customer satisfaction has been the prime focus of

Introduction. for over a period 4 decades now. Customer satisfaction has been the prime focus of Introduction GEMSCAB has been associated with marketing and manufacturing Electric s for over a period 4 decades now. Customer satisfaction has been the prime focus GEMSCAB and today it has established