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Switches flow measurement sensors

The weather station is fitted with various sensors and is capable of monitoring the following parameters Time, indoor temperature, outdoor temperature, barometric pressure, wind direction, wind speed, rainfall and humidity. The water meter used in our demonstration is a Neptune (Neptune Measurement Company, 1984) impulse switch which develops an electrical impulse for every ounce of water flow. [Pg.38]

The optimal robust controller designed with one of the new synthesis techniques is generally not of a form that can be readily implemented. The main benefit of the new synthesis procedure is that it allows the designer to establish performance bounds that can be reached under ideal conditions. In practice, a decentralized (multiloop) control structure is preferred for ease of start-up, bumpless automatic to manual transfer, and fault tolerance in the event of actuator or sensor failures. Indeed, a practical design does not start with controller synthesis but with the selection of the variables that are to be manipulated and measured. It is well known that this choice can have more profound effects on the achievable control performance than the design of the controller itself. This was demonstrated in a distillation example [17, 18] in which a switch from reflux to distillate flow as the manipulated variable removes all robustness problems and makes the controller design trivial. [Pg.531]

The performance of the two-layer blend FET sensor upon exposure to dilute DMMP vapor was further studied in a test chamber connected to a constant flow rate of gas, which was switched between N2 and DMMP vapors. A bubbler containing DMMP liquid was used as the source of analyte vapor. Nitrogen gas was passed above the liquid surface and carried the analyte vapor to the test chamber. The mass of a bubbler was measured before and after testing to determine the total mass of analyte delivered by a specific volume of carrier gas, thereby allowing calculation of the average concentration of analyte vapor in the test chamber. [Pg.230]

Notice that element C Ci in derivative causality and the switch Sw in conductance causality do not allow a flow sensor Df / in inverted causality attached to junction 11. The non-inverted flow sensor Df / has been replaced by a virtual detector Df r for residual n and a modulated flow source MSf /. Virtual detectors are distinguished from detectors of power variables by an asterisk. The modulated flow source delivers a measured flow /. [Pg.77]

Field sensors are used to collect information necessary to determine if an emergency situation exists. The purpose of these sensors is to measure process parameters (e.g., temperature, pressure, flow, etc.) or monitor the process condition/status, used to determine if the equipment or process is in a safe state. Sensor types range from simple pneumatic or electrical switches to smart transmitters with on-board diagnostics. These sensors in some applications are dedicated to SIS. Manufacturers approach, in line with lEC 61508 towards the development of sensor, shall include but is not limited to the following ... [Pg.625]

Flow Rate Measurements, Methods, Figure 13 Response of flow sensor at very low flow rates, (a) Instantaneous current values when the flow was varied and switched. The results in (a) are replotted in (b). The velocities of beads at different flow rates of the fluid are also shown on the right axis of (a). (The peaks in (b) correspond to the flow rate values labeled) [6]... [Pg.714]

Measurements with ISFET require the sensors to be calibrated periodically This is done by switching the fluid flow between the sample and calibration fluid We have... [Pg.290]

Depending on the cross section of the molded part and the corresponding flow resistance of the melt, a pressure increase is measured during mold filling. After switch over to holding pressure, the melt is compressed, and there is a rapid pressure increase. Because of the pressure transfer in the polymer melt from the flow path end up to the sensor position near the gate, it takes some time for the increase in pressure to be measured, and that is why a cavity pressure-dependent switchover to holding pressure tends to be too late. [Pg.650]


See other pages where Switches flow measurement sensors is mentioned: [Pg.289]    [Pg.63]    [Pg.216]    [Pg.273]    [Pg.292]    [Pg.20]    [Pg.72]    [Pg.163]    [Pg.496]    [Pg.155]    [Pg.369]    [Pg.287]    [Pg.105]    [Pg.415]    [Pg.854]    [Pg.309]    [Pg.139]    [Pg.162]    [Pg.161]    [Pg.969]    [Pg.970]    [Pg.171]    [Pg.274]    [Pg.191]   
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