| 摘要 |
<p>PURPOSE:To determine whether a dead time and a stroke time are a prescribed value or not, by measuring the dead time based on the position of a valve rod of an air-driven type on-off valve and then, the upper limit and the lower limit of the action thereof to determine the dead time and stroke time automatically from both of the measured values. CONSTITUTION:An abnormality diagnosing apparatus of a dead time is so constructed that a signal from an operator 5 is converted to the signal of a level appropriate to an electric computation with a set value converter 6. The position of a valve rod 3 is converted to a signal of a level appropriate to an electric computation with a position detector 7 and a position converter 8. Outputs of the set value converter 6 and the position converter 8 are compared and computed with differentiation computing units 9 and 10 and comparison computing units 11 and 12 and constant outputs Ic and Sc are taken out separately. As outputs of the differentiation computing units 9 and 10 have positive or negative code, the comparison computing units 11 and 12 work to either the output of positive or negative code.</p> |
