A cable that is 20% cheaper is not a bargain if it starts a fire, fails an inspection, or quietly overloads for years before causing equipment damage. Electrical cable is one of the few components where cutting cost means cutting safety margin. Here is what buyers need to understand before purchasing.
What Sub-Standard Cables Actually Look Like Inside
Non-BIS cables pass casual visual inspection, they look like proper cables. The problems are hidden:
- Undersized conductor: A cable marked "2.5 sqmm" may have only 2.1, 2.2 sqmm of actual copper. That 15% deficit means the cable runs hotter under the same load, permanently.
- Thin insulation: IS 694 specifies minimum insulation thickness. Cheap cables thin the insulation to save PVC compound cost. Thinner insulation has lower dielectric strength and degrades faster with heat cycles.
- Low-grade PVC compound: Standard PVC with poor plasticizer choice becomes brittle within 2, 3 years. The insulation cracks during normal thermal cycling, creating short circuits.
- No aluminium in "copper" cables: Some unscrupulous products use copper-coated aluminium strands. Aluminium has 60% of copper's conductivity, a hidden underrating of the cable.
How Cable Quality Failures Manifest
| Failure Mode | Symptom | Timeline |
|---|---|---|
| Undersized conductor | Cable runs hot, breaker trips, voltage drop | Immediate on load |
| Thin insulation | Insulation breakdown, earth fault, fire | Months to years |
| Poor PVC compound | Insulation cracks on bends, intermittent faults | 2, 4 years |
| Copper-coated aluminium | Overheating at terminations (high resistance), joint failures | Months |
| Non-FR PVC | Fire propagation along cable tray in any fault | Any ignition event |
The Insurance and Legal Position
Industrial fire insurance policies in India typically include a clause requiring electrical installations to conform to IS standards. If an electrical fire is traced to non-BIS cables, the insurance claim can be rejected. Rebuilding a manufacturing plant after a fire, even a partial one, without insurance recovery is catastrophic for a business.
Under the Electricity Act 2003 and CEA (Measures Relating to Safety and Electricity Supply) Regulations 2010, the consumer is responsible for the electrical installation inside the premises. Using sub-standard materials creates personal liability for the owner in the event of an accident.
The Real Cost Comparison
Non-BIS cable: ₹28/metre Ã, 2,000m = ₹56,000
Polycab BIS-certified FR cable: ₹35/metre Ã, 2,000m = ₹70,000
Difference: ₹14,000
Cost of one factory shutdown day due to electrical fault: ₹50,000, ₹5,00,000+
Cost of rewiring after insulation failure (labour + material): ₹2,00,000+
Insurance claim rejection after fire: entire rebuild cost
The ₹14,000 saving is not a saving. It is an unquantified liability.
How to Verify Cable Quality at Purchase
- Look for the ISI/BIS mark moulded into the cable jacket, not just printed on the drum label
- Check the cable drum for IS number (IS 694 for house wire, IS 1554 for power cables, IS 7098 for XLPE)
- Measure the actual conductor diameter with a vernier, it should match the sqmm marking
- Polycab cables include the BIS licence number printed on the cable sheath, traceable online
Polycab Quality Assurance
Polycab is India's #1 cable and wire company by revenue, with manufacturing facilities certified to ISO 9001, ISO 14001. Every drum undergoes routine and type testing per IS standards. As an authorised Polycab distributor, Masa Technologies stocks only genuine material purchased through the official Polycab distribution network, with traceability from the drum to the manufacturing batch.