| 摘要 |
PURPOSE:To prevent a monitoring device from erroneously operating upon starting of a turbine at a high speed-up rate, by providing vibration and speed detectors to the turbine so that the limit values of vibration amplitude and amplitude changing rate are selected in accordance with the speed-up rate of the turbine to monitor vibrations. CONSTITUTION:A vibration amplitude abnormal detecting circuit 2 receives signals from a steam turbine vibration amplitude detector 1 and a vibration amplitude changing rate circuit 3. Meanwhile a signal from a turbine speed detector 7 is delivered to a switch 6 through a speed-up rate discriminating circuit. This switch 6 has a contact 6a for switching between amplitude limit value circuits 4a, 4b having different set values. Upon starting of the turbine when the discriminating circuit 5 switches the contact 6a in accordance with the speed-up rate of the turbine, the detecting circuit 2 determines whether vibration amplitudes and amplitude changing rates are within their stable ranges or not, and closes alarm issuing contacts 21a, 21b or a turbine stopping contact 22 if they are in a dangerours range. |
