This IEE Regulation provides a table of current carrying capacities of cables that are run on perforated cable trays. This will lower the actual maximum current that the cables can actually handle.
If the energy dissipated in the form of heat is not carried away from the cables, the cables will heat themselves up and effectively operate at the higher temperature than the actual surrounding air. This air movement can effectively help cool the cables on the tray.Īll electric cables carrying current dissipate some power because of the resistance of the current carrying conductors. The term perforated usually is defined as holes provided to the sheet of the trays to allow the movement of airflow that can provide a more natural flow of air circulation around the electric cables. Picture 1 – Cable tray at high level inside a chiller plant roomĬable trays for the installation of electric power cables are usually specified as perforated hot-dipped galvanized sheet steel. If you wish to see more photos of electrical installations, this post, Free electric installation pictures. At the end of these pictures, you will also find a sample specification for the cable tray and cable ladder installations in multi-storey office buildings. I have uploaded a few pictures and a diagram on the installation of electrical cable trays and cable ladders for those who have some need for them.
