Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. In electricity distribution networks, spot network substations are used in interconnected distribution networks. They have the secondary network (also called a grid network) with all supply transformers bussed together on the secondary side at one location. Spot networks are considered the most reliable and most flexible arrangement of connecting power to all types of loads. Switching can be done without interrupting the power to the loads. Electricity distribution networks are typically of two types, radial or interconnected. A radial network leaves the station and branches like a tree with no connection to any other supply. This is typical of long rural lines with isolated load areas. In general, the radial distribution network has more power failures than the interconnected distribution networks.