| 摘要 |
PURPOSE:To enable a higher reliability with an acurate action for reoperation of two systems of sampling apparatuses by starting the water sampling of the one system which has been standing by after the washing thereof at the switching of the operation of the system. CONSTITUTION:In the operation of one system, water is sampled with an underwater pump 1 and after filtered with a filter 2, fed to an automatic water quality measuring apparatus passing through valves 3 and 4. During the period, an underwater pump 5 and a filter 6 of the other system is kept standby while a valve 7 is closed. When the water sampling time of one system is finished, the sample water flows sequentially through the underwater pump 1, the filter 2, the valve 3, the valve 7, the filter 6 and the underwater pump 5 so that the filter 6 and the underwater pump 5 are backwashed in the other system before changed over to the other system. Upon the end of the backwashing, the changeover in the system is made and the sample water sent in the same manner to the automatic water quality measuring apparatus. This eliminates temporary turbidity of the water otherwise caused at the starting of the water sampling while removing muddy matters and soil thereby improving the reliability. |
