Due to the use of cables in different conditions, the requirements for different properties of these cables are justifiably indicated. And in each individual case it is necessary to look for different conditions and options in order to make the network relatively inexpensive, functional reliable. Often it makes sense to use inexpensive cable for this. But if the weather conditions are difficult, then the cable must be chosen more expensive and high -quality. And in this situation a solution is considered to be a rational, which, from the point of view of savings, is not the most profitable. But at the same time, it will achieve reliable and uninterrupted energy supply.