| 摘要 |
PURPOSE:To enable to continue operation of a compressor system without disturbing a closed cycle, by employing such an arrangement that a next compressor is set into operation when a compressor having some trouble or operated alone, out of a plurality of compressors constituting a closed cycle comes to its turn for operation. CONSTITUTION:In case that a first compressor has some trouble or is operated alone, a contact 36a1 is closed and a contact 36b2 is opened. Similarly, in case that a second or a third compressor has some trouble or is operated alone, a contact 38a1 or 3Ba1 is closed and a contact 38b1 or 3Bb2 is opned. Therefore, the turn for operation comes to the second compressor. Here, if the second compressor also has some trouble, current is passed from B1a1 via 38a1 to Y22, and the relay Y22 is energized. Then, current is passed from Y22a1 to A0, and the relay A0 is energized, which causes energization of a stepping relay SP1 and advances it by one step, so that a relay B2 is energized. Resultantly, current is passed from B2a1 via 3Bb2 to Y33, so that the relay Y33 is energized. Then, current is passed from Y33a1 to a relay 54, and the relay 54 is self-held. Thus, the third compressor is set into operation. |
