Measuring Gas Velocity with the D-FL 100 Differential Pressure Bar

D−FL 100 Seite 19250 mm13538,5 188,5[B]246230170[B][B]B = 3-Punkt-WandbefestigungsbohrungenØ 5mmG11-01-006120M20 x 1,5M16 x 1,567Fig. 18:Dimensions of D-FL 100-G (fieldhousing for 19-inch rack)4.4. Purge Air ConnectionIn order to clean the differential pressure bar, or to keep it clean, it is recommended to havecompressed air inside the pressure chambers. The compressed air can be used to purge the pressurechambers of the differential pressure bar. The flow of purge air is controlled by the switching valve. Ifthere is no purge air (compressed air: 6-8 bar) at the measuring point, a simple compressed air bottlewill do. Backflow intervals are rarely very short. The frequency of the need for cleaning depends on thedust load in the exhaust stack and on the application. Generally, the differential pressure bar should becleaned at intervals of several weeks or months.If the chambers in the differential pressure bar are so clogged that purge air will not clean them, removethe differential pressure bar and adapter piece and clean the interior of the bar mechanically.GmbH