How to choose a cable section? The paramount value for choosing the cross-section of the wire is to determine the characteristics of electrical equipment, which will subsequently consume electricity and be in the network. If more than one electricity consumers will be present in this network, then for this section their capacities are summed up. Next, you need to calculate the permissible current load and determine its duration. Also, do not forget about the operating conditions of the power grid and the method of laying it (open or closed).