Empirical Analysis of Core Diameter and Insulation Thickness of House Wiring Cables in Nigeria

Abstract

The diameter of metal conductor (core) and insulation thickness of copper cables produced by some Nigeria manufactures was assessed in this study as preliminary search for the basic the cause of incessant fire outbreaks traceable to overheating of electric wires in our residential and work places. Colman, cutix, and scan, wesco cables with cross sectional area ranging from 1mm2 to 16mm2 obtained from our industrial markets were sampled and compared with set standards. Results revealed that the core diameters of some cable sizes with high demand in house wiring (1mm2, 2.5mm2 and 4mm2) were short of Nigerian Industrial Standard while other (1.5 mm2, 6mm2, 10mm2 and 16mm2) with less demand profile conformed. The 1mm2 cables of Wesco and Scan exhibited average core diameters of 1.13mm and 1.12mm which are below the expected minimum of 1.15mm while all fall short of the minimum core diameter of 1.82mm expected of 2.5mm2 cables. Scan cables also fall short of the minimum diameter expected of 4mm2 cable. In addition all the cables sampled were adequately insulated because their insulation thickness are far greater than the expected value. This showed that some of the manufactures uses the excess insulation to make up the short fall in the diameter of the metal conductor to scale through the expected total diameter of the cable, thereby making it difficult to notice their short practices by mere physical observation of the cable. Thus, the overheating of the cables during service and its consequential high rate of fire outbreak in this country is caused by the reduction in the core diameters of some electrical cables used in our house wiring. It is therefore recommended that Nigeria regulatory agencies and cable producers should step up fight against piracy in this sector to save the nation from this fire inducing scourge.