| 摘要 |
PURPOSE:To stabilize Y-DELTAstart by rotating a compressor for a certain time before normal starting operation and by coming into normal Y-DELTAstart after a short interval. CONSTITUTION:When a push button 11 is pushed, time relays 26, 28 start counting, a relay 3 is excited as a reverse contact 16 and time limit reverse contacts 15, 31 are closed, and a contact 4 is closed to form Y-connection, whereby a motor 1 is started (Y). After a certain time T2, the time relay 26 works to open the time limit reverse contact 31, the relay 3 opens the reverse contact 16 losing its energy and stops the motor 1 for a short time T3. Then, the time relay 28 works to close time limit contacts 29, 30, whereby the motor 1 is started (Y) again and counting of a change-over time for DELTA-connection is started by a time relay 13. The operation time due to Y-start corresponding to above- mentioned time T2, serves to rotate a compressor beforehand to eliminate oil in a casing. |
