The NKU is connected up with the power circuit 3 TN, 50 Hz, 380/220 V by switch with current up to 250 A. Voltage rating of control circuits is no more than 42 V, 50 Hz. Overall dimensions are 500 x 800 x 1600 mm. Weight si no more than 230 kg. The cabinet's door have special key. The NKU must be operated in open spaces at the temperature from minus 5 to plus 40 °C and at relative humidity to 85% at 20 °С. Protection degree is IP 44. Average specific life is no less than 10 years. The NKU cabinet structure is manufacturable at productions, mounting, operations and maintenance.