According to National Standards Authority of Ireland (NSAI), the ETCI Cables Technical Committee was asked to examine the size of the protective conductor due to changes in the Building Regulations and materials being used, for example, of plastics plumbing systems etc.
Following a lengthy technical examination and the well-established practice of all other cable types, the solution proposed was to increase the protective conductor size to the identical size of the phase and neutral conductors. It was also proposed to insulate the protective conductor departing from the current bare earth type.
In 2013, NSAI published a revision to the standard I.S. 201- 4 entitled “Polyvinyl Chloride Insulated Cables of Rated Voltages up to and including 450/750v – Part 4: PVC and Low Smoke Halogen Free Sheathed cables for fixed wiring”.
This standard was adopted by the Electro-Technical Council of Ireland (ETCI) in the National Wiring Rules and covers the complete range of cables for domestic fixed wiring including Twin and Earth along with NYM types. The new standard includes 6mm2, 10mm2 and 16mm2 twin and earth cables with flexible conductors. All of these cables include both PVC and Low Smoke Halogen Free versions.
WHO DOES IT AFFECT?
This amendment, called Amendment No. 2.2 to the National Rules for electrical installations ET 101, affects manufacturers of electrical cables, electrical contractors and electrical installers. From September 5,2017, all electrical installers and electrical contractors must ensure they only use the new type of cables (as described in the amendment).
NSAI recently established the Electro-Technical Committee which, in future, will be responsible for all standards, including the National Wiring Rules for the electro-technical sector. The new Electro-Technical Committee, dealing with wiring rules, held its first meeting in December 2016. Safe Electric is responsible for regulating the activities of Registered Electrical Contractors (RECs).
This change will, says Dominic Dunne, Managing Director at Metac Training, have a considerable effect.
“Conduit manufacturers may well have to increase the size of conduits to support the larger cables. This in turn might mean that the size of chases may also need to be enlarged to house the larger conduits. Metal and plastic boxes, fittings etc may also have to increase the size of their openings to be compatible with the larger conduits and cable.”
For more on the amendment, visit www.etci.ie