Low-voltage wind of a low-power transformer's index reliability definition

Reliable work of any electrotechnical construction is in general defined by reliable work of it's insulation system. An insulation system of low-power transformers's coils includes the following elements: magnet wire insulation with impregnated compound, winding insulation from magnet core, layer insulation, winding insulation and external insulation. The main characteristics of insulation determined by reliability of electrical devices is it's breakdown strength. Calculated method of index reliability definition is suggested here. The calculation is made by insulation element with taking into account the number of defects. Open-ended damage in insulation is taken as defects.