| 摘要 |
PURPOSE:To enable to early detect a malfunction in a rotary electric machine by detecting a thrust bearing for supporting the machine as a malfunction by the operation of an accleration delay relay when the machine does not reach the prescribed speed within the prescribed period of time. CONSTITUTION:A pumping-up power plant motor or the like is accelerated by a thyristor starter, a contact 81 is closed by the energization of an interrupting operating acceleration delay timer 8 after the prescribed time, and a contact 9 is simultaneously opened by switching to a continuous acceleration mode, thereby starting it. When a malfunction exists in a thrust bearing and the frictional resistance increases to cause an interrupting operating acceleration time to increase, an interrupting operating acceleration delay relay 10 is operated to close a contact 101 to energize a lockout relay 11, thereby stopping the starting of pumping up. Accordingly, the malfunction of the thrust bearing at the extremely initial time can be accurately detected, thereby suppressing the damage to the minimum. |
