Appointment breakers disconnectors are used to create a visible gap that separates derived from the work of conductive equipment parts which are under stress. This is necessary, for example, in the derivation equipment repairs for the safe production work. Disconnectors have no arcing devices and therefore are intended primarily to enable and disable the electrical circuits in the absence of current load and are only under stress or even stress-free. In the absence of a circuit breaker in the electrical, 6 – 10 kV is allowed to enable and disable disconnectors small currents significantly rated currents smaller vehicles, as described below. The requirements for disconnectors Requirements for disconnectors in terms of maintenance of their operational staff are as follows: 1) breakers should be clearly marked to create an open circuit, the voltage corresponding to the class setting, and 2) drives breakers must be capable of rigid fixation of the knives in each of the two operative provisions: enabled and disabled. In addition, they must have reliable stops that limit rotation of knives at an angle greater than a given, and 3) circuit breakers should be turned on and off at any of the worst environmental conditions (Eg, icing), and 4) support insulators and insulating rod must withstand the mechanical stresses resulting from operations, and 5) the main blades should have a lock disconnector with grounding blades device, eliminating the possibility of simultaneous operation of both. Classification and disconnector unit Individual types of disconnectors, 6 – 10 kV differ from each other by the nature of the installation (break the inner PB, EEO, RVF, RVFz and outdoor RLN, RLND, RLNDz, RD, RDZ installation) on the number of poles (single-pole circuit breakers PBO and pole), and the nature of the knife (break a vertically rotating and tilting type .) Three-pole circuit breakers operated lever drive (PR-10, PRN s), single – operational insulation rod. .