Digital Differential Display

The first question is what kind of information the chemical control can and should provide. Must it be a qualitative and/or quantitative analysis, is it based on a one- or two-dimensional measurement and should the latter consist of an analog and/or digital display The meaning of all this can be well illustrated by the example of the differential titration (see Fig. 5.1) of equivalent amounts of a strong acid (cf., Fig. 2.17, AA) and a weak acid (cf., Fig. 2.18, BA, pK, = 4). 

A2.2.6.1 Proper use of these differential measuring devices requires two special actions bypass and air bleeding. The first allows the fuel flow to bypass the filter whenever that action becomes necessary. The second is used to remove air or nitrogen that at times may become trapped in the cell chambers. The manometer output is read as the height of the column of mercury the transducer output must be displayed digitally. 

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