Many people wonder why the self-supporting wire cip came to replace the speaker wire that is used for many decades in our country. I will cite several arguments in favor of sit. Characteristics of the wires and sip as (comparison): Criteria sit as Application for transfer and distribution of electric energy in air power and lighting networks of up to 20 kV. Intended for overhead power lines and to enter into homes and other buildings. Transmission of electric energy in the air networks of land of any climatic regions with temperate and cold climates. The design consists of four twisted insulated wires, the one for each of the three phases. The fourth phase wires running simultaneously as the rotor and serves as a zero-worker, or combined conduit. Aluminum wire aluminum wire with steel core – the round. Short circuits due to weather conditions do not let the possibility of new connection fees without disconnecting from the power previously mounted yes no yes no Fire unauthorized connection consumers have so little high electrical injuries Aesthetics yes no complexity of electrical work do not let the low cost of installation of the high possibility of mounting on the facade of buildings in urban conditions, so there is no lack of insulators and traverse yes no losses associated with high leakage current low reactance lines lower the high costs of operation low-high cost of installation average high Technical Data bare wires of type A, ac and self-supporting insulated wire-type sts. Electrical resistance of the cross section of 1 km of wire direct current at 20 C, om, no more: A phase ac sit sit lived carrier core 16 1.8007 1.7817 1.910 25 1.1498 1.1521 1.200 1.380 35 0.8347 0.7774 0.868 0.986 50 0.5784 0.5951 0.641 0.720 70 0.4131 0.4218 0.443 0.493 95 0.3114 0.3007 0.363 120 0.2459 0 , 2440 .253 As you can see the wires cip almost all indicators exceed the speaker wire. Therefore recommended for use.