| 摘要 |
1. Automatic system for controlling high voltage motors insulation condition before the motors are restarted after prolonged stoppage, adjusted for making control measurements in multi-field high voltage switching stations, especially in deep mines, and comprising for each controlled high voltage driving motor a voltage transformer, with one end of its high voltage winding connected to one supply phase, and the other end of its high voltage winding connected to earth, whereas the secondary low voltage winding of that transformer is connected to the measuring circuit powered with low voltage alternating current through a cable disconnector contact, characterised in that it has a high voltage semiconductor diode (3-k) inserted in series between one supply phase of each controlled high voltage driving motor (2-k) and one end of the high voltage winding of the relevant voltage transformer (1-k), whose other end is connected to earth, whereas the secondary low voltage winding of that voltage transformer (1-k) is connected in series through the closing contact (5a-k) of the cable disconnector (5-k), and the opening contact (6a-k) of the high voltage isolating switch (6-k) and the closing contact (10a-k) of the relevant control transformer (10-k) to the common measuring circuit of the threshold relay (11) with the resistance meter (12), connected to the low voltage alternating current feeder (14).<IMAGE>
|
