Investigation of the problems on electrical earthing system of construction
YU Hua-jing · Journal of Liaoning Technical University · 2003
According to the relative standards, the author analyzes and studies several problems on electrical earthing system of construction, i.e., selection of the earthing type, protected measures of earthing troubles, selection of earthing instructions. The earthing type of low voltage distribution system should use TT system when low voltage sources is used outdoor, while the TN-S system should be adopted when 10/0.4KV distribution transformer is used as power supply, this paper discusses electrocution protected instructions to be used earthing trouble protection and how to determine its current setting values, different types of earthing should select different earthing instructions, in order to overcome the difference of electric potential, equal electric potential connection should be done at entrance of power supply and somewhere, that is to say, workers are very easy to be injured when some electrical apparatus are out of control.