| 摘要 |
<p>A differential pressure monitor (50) for measuring the pressure at a plurality of heights in a filter bed (38) is provided. A preferred embodiment of the monitor (50) includes an elongated body (70), a plurality of pressure sensors (56) located on the elongated body (70), for obtaining the pressure readings, a control means (80) for determining differential pressures from the pressure readings, each differential pressure being the difference in pressures measured at two different heights in the filter bed (38), and transmission means (62) to transmit the pressure readings from the pressure sensors (56) to the control means (80).</p> |
