Home » construction of 33/11KV & LT overhead line

The primary purpose of an electricity distribution system is to meet the customer's demand for energy depending on the geographical location, the distribution network can be in the form of overhead lines or underground cables. Cables are commonly used in urban areas and overhead lines are adopted for rural areas. Different networks configurations are possible in order to meet the required supply reliability.

Planning of the distribution network is essential to enable the required demand can be met based on various forecast loading figures and supply security/reliability. There are three categories of planning, namely the long-term planning , the network planning and construction planning. Long-term planning is to determine the most optimum network arrangements and the associated investment with consideration on future developments. Stage-by stage development must be in line with the forecasted load growth so that electricity demands can be timely met. The construction planning or design or design is the actual design and engineering work when the required circuits and substation have been planned and adopted.

Distribution network refers to those 33kV or 11kV network supplying electricity to customers through overhead line (OHL). From primary substation to various customer substation. OHL network is more likely to be disturbed by external factors for example, lighting, animals or plants. Some of the disturbances are temporary so the circuit breakers at the source end substation are equipped with auto-reclose capability to cater for transient fault. In long OHL situation , auto-recloser can be adopted. Modern approach is the use of pole mounted switch with remote control facilities. The installation of lighting arrester can improve the transient response capability of the OHL. Regular maintenance like a vegetation management program can reduce unnecessary tripping particularly during a possible line overhead situation. Such measures could minimize the impacts resulting from these external disturbances.