Manufacturing · Greater Noida · Established 1972

From copper rod to finished drum.

National Cables operates a fully integrated manufacturing facility in Greater Noida — handling wire drawing, annealing, stranding, insulation, sheathing, and testing under one roof. No outsourced processes. No third-party compounds. One point of manufacturing accountability.

400mm²
Max rigid-strander conductor
IS 694:2010
+ 4 Amendments
100%
Lot-level testing before dispatch
99.97%
Electrolytic Grade Purity (Conductivity ≥ 101% IACS)
Production Flow

Eight stages. Zero outsourcing.

01
Copper Rod
02
Drawing & Annealing
03
Stranding
04
Insulation
05
Laying Up
06
Sheathing
07
Testing
08
Dispatch

Process Detail
Stage 01
IS 8130:2013
Wire Drawing
Electrolytic-grade copper rod is drawn in multiple reduction passes: tungsten-carbide dies handle the heavy intermediate reductions; finishing passes use PCD (polycrystalline diamond) dies to hold the tight diameter tolerance and roundness required for Class 5 fine-stranding. Each pass reduces the cross-section by a controlled ratio, building up the tensile properties of the wire without embrittlement. Die wear is monitored continuously — a worn die produces a conductor that is out-of-round, which affects both resistance and insulation adhesion downstream. Online diameter measurement at the final draw confirms dimensional compliance before the wire moves to annealing.
99.97% Electrolytic Grade Purity (Conductivity ≥ 101% IACS) Tungsten-carbide + PCD finishing dies Real-time diameter monitoring IS 8130:2013 conductor specification
Stage 02
IS 8130:2013
Online Annealing
Drawing work-hardens copper — it becomes stiffer and more brittle with each reduction pass. Annealing restores ductility by heating the wire to a controlled temperature and cooling it in a protective atmosphere, preventing oxidation of the freshly-drawn surface. Our process uses continuous inline annealing immediately after the final drawing stage — meaning every meter of wire is thermally treated as a continuous process, not in batch ovens. This eliminates the variation between start, middle, and end-of-coil that batch annealing produces.
Zero work-hardening Continuous inline process Controlled atmosphere — no oxidation
Stage 03
IS 8130:2013
IEC 60228
Stranding & Bunching
Conductor assembly follows the process defined for each class under IS 8130:2013 and IEC 60228. Class 2 (rigid, fixed installation) conductors are built on tubular stranders with a longer lay for compactness. Class 5 (flexible) conductors are produced on high-speed double-twist bunching lines — the softer lay and bundle geometry needed for flexibility are not achieved on rigid stranding equipment alone. The stranding pitch — the length of one complete helical turn — is controlled per standard for each class. Automated tension control on pay-off and take-up maintains uniform lay across the full drum length, preventing conductor deformation that causes hotspots at termination points.
Class 2 — tubular stranding Class 5 — double-twist bunching IS 8130:2013 / IEC 60228 lay control Automated tension control Rigid strander to 400mm²
Stage 04
IS 5831:1984
IS 694:2010
Insulation Extrusion
PVC compound is applied over the conductor by precision extrusion. The extruder maintains a uniform melt temperature to ensure consistent insulation wall thickness throughout the drum length. IS 694:2010 specifies minimum nominal insulation thickness for each conductor cross-section and the permitted reduction at any point — our process controls both. General PVC insulated wiring cables use insulation compound Type D per IS 694:2010 (Table 2 / Clause 10.1). Fire performance categories are delivered with FR-grade PVC for flame-retardant classification, FR-LSH compound for low smoke and halogen performance, and thermoplastic HFFR (Type LSH1) per IS 17048:2018 Table 1 for halogen-free wiring cable — not cross-linked XLPE systems.
FR PVC — IS 694:2010 Category FR FR-LSH PVC — IS 694:2010 Category FR-LS Thermoplastic HFFR (LSH1) — IS 17048:2018 Type D — IS 694:2010 Table 2 (general PVC) Inline spark testing at extrusion IS 5831:1984 compound specification
Stage 05
IS 694:2010
Laying Up & Taping
For multicore cables, individual insulated cores are laid up together in a controlled helical pattern. The outermost layer follows a right-hand lay; successive inner layers alternate direction to improve mechanical stability and prevent unwinding under flexing. PVC fillers maintain the circular cross-section of the assembled core bundle. For cables above a specified conductor count, a polyester tape is applied over the laid-up cores before sheathing to maintain the assembly shape and provide a clean interface for the outer sheath. Core identification: 2–5 cores — colours per IS 694:2010; 6–61 cores — black/grey cores with white numbering plus one Green/Yellow earth, per control/multicore practice (standard stock to 24 cores).
Alternating lay direction per layer PVC fillers for circularity IS 694:2010 colour coding Polyester tape for large cores
Stage 06
IS 5831:1984
IS 694:2010
Sheathing & Jacketing
The outer sheath is applied over the laid-up core assembly by a second extrusion stage. Sheath compound selection follows IS 5831:1984: ST1 PVC for general-purpose cables to 70°C, and ST2 for 90°C heat-resistant sheathing. For submersible cables, the sheath compound is specifically formulated for continuous water immersion and abrasion resistance against borewell casing surfaces. The sheath is applied to the minimum thickness specified in IS 694:2010 at any point, with our process targets set above the minimum to allow for measurement variation.
ST1 — 70°C general purpose ST2 — 90°C heat resistant Submersible grade — water immersion
Stage 07
IS 694:2010
IEC 60228
Testing & Verification
Every production lot undergoes a full routine test sequence before coiling and dispatch. Conductor resistance is measured against IS 8130:2013 / IEC 60228 limits for the specified conductor class and cross-section. Insulation resistance is measured per IS 694:2010. High-voltage withstand confirms insulation integrity. Dimensions are verified. Spark testing is conducted continuously during insulation extrusion — not as a final check, but as an inline process monitor that detects pinhole defects at the point of formation. Detailed test results and standard compliance certificates are issued for every institutional and export order.
100% lot-level testing Conductor resistance — IEC 60228 HV withstand — IS 694:2010 Insulation resistance measurement Inline spark test during extrusion Test certificate on every order
Stage 08
IS 694:2010
Coiling, Marking & Dispatch
Standard packing lengths are 90m (small sizes), 100m, 180m, and 500m drums depending on product. Cable marking per IS 694:2010 Clause 17.1 — brand name, standard reference, conductor size, voltage grade, and ISI mark — is applied continuously during sheathing by online inkjet or embossed (indented) marking on the outer surface, not as stick-on labels. Permanent marking at extrusion confirms the legend is integral to the cable. Every drum is tagged with batch number and test reference before storage. Dispatch documentation includes test certificates, packing lists, and BIS licence reference for all ISI-marked products.
Inkjet or embossed marking — IS 694:2010 Clause 17.1 Batch traceability Test certificate issued per order BIS licence reference on all ISI cable

Manufacturing Capability
400mm²
Maximum rigid-strander conductor
Maximum rigid-strander conductor size. Covers the full stocked IS 694:2010 range from 0.5 mm² to 240 mm².
99.97%
99.97% Electrolytic Grade Purity (Conductivity ≥ 101% IACS)
Electrolytic-grade copper rod input. Purity and conductivity verified at raw material intake and confirmed by conductor resistance testing on every lot.
±0.5%
Diameter tolerance
Advanced diameter control technology maintains uniform conductor thickness within ±0.5% — reducing electrical inconsistency and improving current-carrying capacity.
0.5–240
Standard IS 694:2010 range (mm²)
Full range stocked across FR, FR-LSH, LSZH, flexible single core, multicore, and submersible product lines.
100%
Lot-level testing
Not sampling. Every production lot tested for resistance, insulation integrity, and voltage withstand before dispatch. No exceptions for any order size.
54+
Years of continuous production
Same manufacturing facility, same process controls, same specification integrity since 1972. No ownership changes. No production interruptions.

Applicable Standards

Every stage mapped to its governing standard.

Our manufacturing process is aligned to current active standards — not historical editions. Where Indian standards reference IEC equivalents, we verify compliance to both.

Standard Scope Stage Applied
IS 8130:2013Conductors for insulated electric cables — copper and aluminium, Classes 1, 2, 5, 6Drawing, Annealing, Stranding
IEC 60228:2004Conductors of insulated cables — international equivalent to IS 8130:2013Drawing, Stranding
IS 5831:1984PVC insulation and sheath of electric cables — compound types A, B, C, D, ST1, ST2 (reaffirmed 2022)Insulation, Sheathing
IS 694:2010 + Amdt 1–4PVC insulated cables for rated voltages up to 1100V — construction, testing, markingInsulation, Laying, Sheathing, Testing, Marking
IS 17048:2018Halogen-free flame-retardant (HFFR) cables up to 1100V — thermoplastic Type LSH1 (Table 1); 90°C conductor limit Clause 10.3Insulation compound, Testing
IEC 60332-1-2:2004Tests for vertical flame propagation — single cableFinished cable fire testing
IEC 60332-3-24:2018Tests for vertical flame spread — bunched cables (Category C)FR-LSH and LSZH testing
IEC 60754-1Halogen acid gas emission test — HCl <0.5%FR-LSH and HFFR compound testing
IEC 61034-2Smoke density measurement — light transmittance ≥70%FR-LSH and HFFR testing
IS 10810 (Part 58):1998Oxygen Index test — minimum OI per product categoryInsulation and sheath compound
IS 10810 (Part 64):2003Temperature Index test — minimum TI per product categoryInsulation and sheath compound

VERTICAL INTEGRATION

National Cables controls every manufacturing stage in-house: copper drawing, annealing, stranding, insulation, sheathing and testing.

All conductor resistance, insulation thickness, and fire-performance results reflect a single controlled process from raw material intake to finished drum.

Test certificates and compliance documentation are issued for every institutional and export order.

Quality Assurance

Control at every stage — not just at the end.

Raw material intake
Copper purity verified on arrival. PVC compound tested for density, thermal stability, and mechanical properties. Batch tracking from intake to finished product.
In-process monitoring
Inline diameter measurement during drawing. Continuous spark testing during insulation extrusion. Tension monitoring during stranding. Real-time alerts on deviation.
Routine testing
Every production lot: conductor resistance, insulation resistance, high-voltage withstand, dimensional check. No exceptions. Results recorded and retrievable by batch.
Type testing
Fire performance, thermal aging, mechanical strength, and long-term insulation stability tested at BIS-recognised laboratories to IS 694:2010, IS 17048:2018, and IEC protocols.

Test certificates, BIS licence reference, and manufacturing process documentation are available on request.

Frequently Asked Questions

Manufacturing — common technical questions.

What MEP consultants, EPC procurement teams, and BIS auditors typically want to verify about National Cables' production capability.

What is the maximum conductor cross-section National Cables manufactures?

The facility operates a rigid strander handling up to 400 mm² conductor cross-section, covering the full stocked IS 694:2010 range from 0.5 mm² to 240 mm² in standard production. Class 2 (rigid, fixed installation) conductors are built on tubular stranders with a longer lay for compactness; Class 5 (flexible) conductors are produced on high-speed double-twist bunching lines required for the softer lay and bundle geometry that flexibility demands.

Stranding pitch is controlled per standard for each conductor class, with automated tension control on pay-off and take-up to maintain uniform lay across the full drum length.

What copper grade is used, and how is conductivity verified?

All production starts with 99.97% electrolytic-grade copper rod, with conductivity ≥ 101% IACS. Purity and conductivity are verified on every raw material intake, then re-verified by conductor resistance testing on every production lot against the limits in IS 8130:2013 and IEC 60228.

Conductor diameter tolerance is held to ±0.5% through inline measurement during drawing, reducing the electrical inconsistency between stranded conductor sizes that can otherwise cause hotspots at termination points.

What insulation compounds are used for FR, FR-LSH, and HFFR cables?

General PVC cables use Type D compound per IS 694:2010 Table 2 (70°C general purpose). Fire-retardant grade uses FR-grade PVC for the flame-retardant classification. Low-smoke-and-halogen variants use FR-LSH compound formulated for reduced smoke density and limited halogen acid gas emission.

Halogen-free wiring cables use thermoplastic HFFR (Type LSH1) per IS 17048:2018 Table 1 — not a cross-linked XLPE system. Inline spark testing runs continuously during insulation extrusion (not as a final check) to detect insulation pinholes at the point of formation.

How is each production lot tested, and what documentation is supplied?

Every production lot undergoes 100% lot-level testing — not statistical sampling — before coiling and dispatch. Routine tests include conductor resistance (IS 8130:2013 / IEC 60228 limits), insulation resistance per IS 694:2010, AC high-voltage withstand, dimensional verification, and the inline spark test record from extrusion.

Cable marking per IS 694:2010 Clause 17.1 — brand, standard reference, conductor size, voltage grade, ISI mark, and BIS licence number — is applied continuously during sheathing by inkjet or embossed (indented) marking, never stick-on labels. Test certificates and BIS licence references are issued for all institutional and export orders.

Request a facility audit or technical documentation.

Test certificates, BIS licence reference, and manufacturing process documentation are issued for all institutional and export orders.