| 摘要 |
<p>FIELD: flotation process. SUBSTANCE: invention relates to flotation enrichment of ores and can be applied in all areas were stirring apparatuses are employed. Device contains low-side vertical asynchronous motor connected to electrical network over frequency converter 5. The latter is concatenated to control unit, program unit, time transducer, and frequency converter power-supply switch. To the second input of program unit, motor power transducer is linked. Frequency converter is switched on with frequency and voltage corresponding to the maximum rotation moment of motor and nominal phase sequence, after which phase sequence is inverted. Phase inversion is performed within period of time allowed by duration of motor start. At the end of indicated period, frequency and voltage are reduced to values ensuring nominal current in the stator of motor. Further, when resuming phase sequence, time required for motor cooling is measured and motor switch-on cycle is repeated. EFFECT: automated start of stirrer. 1 dwgy</p> |
