摘要 |
<p>A differential pressure sensor is attached to a process via a high and a low pressure impulse line. An absolute pressure sensor is also attached to each impulse line. To determine if an impulse line is blocked, a noise signal is acquired from the corresponding absolute pressure sensor. A variance of the noise signal is determined and compared to a threshold. If the variance is less than the threshold, an impulse line blockage is indicated.</p> |