Electrical Trunking provides very good protection to enclosed conductors from impact, moisture, and chemical vapors. Varying numbers, sizes, and types of conductors can be pulled into a trunking, which simplifies design and construction compared to multiple runs of cables or the expense of customized composite cable. Wiring systems in buildings may be subject to frequent alterations. Frequent wiring changes are made simpler and safer through the use of electrical trunkings, as existing conductors can be withdrawn and new conductors installed, with little disruption along the path of the trunking. Cable Trunking Advantages: · Cheap and easy installation method. · The cables are enclosed in trunking, there is no risk of cable insulation to be damaged. · Cables are safe against dust and humidity. · Alternations are possible. · Trunking systems has a long life. Disadvantages: · Expensive compare to other wiring systems. · Care and good workmanship are needed to ensure a successful installation.