Front panel

The programming language has mainly two parts the front panel and the block diagram. 

The front panel is the outlook for setting input values and viewing outputs, in this case E/C data. 

A section view at defect height permits a detailed analysis. Printouts of the front panels are made by clicking. 

The block diagram accompanies each front panel and contains the graphical program. 

Figure 13.7 Side view of a double front panel with a common horizontal bus, but separate vertical bus bars (not visible) (Courtesy ECS)...

In outdoor type switchgear or controlgear assemblies the normal practice is to provide a double door in the front to house the front panel and protect the door knobs, meters, lights, pushbuttons, reset knobs or other accessories mounted on the door and thus prevent water or dust leaking through joints, knockouts and fitments etc. It is also recommended to have a canopy on the top of the enclosure to protect the panel from direct rain. Figures 13.6 and 13.28 illustrate this type of construction. 

Then, the corresponding relationship between lateral voltage of the four-quadrant position detectors (F/) and the torsional angle of the cantilever ( di). Thus we can obtain the variation of torsional angle 0i through reading the variation of lateral voltage (F ) from the front panel. 

A reminder is that a controller has a front panel with physical units such as °C. (Some also have relative scales of 0-100%.) So when we dial a change in the set point, the controller needs to convert the change into electrical signals. That s why Km is part of the controller in the block diagram (Fig. 5.5). 

Figure 32 shows the front panel of a typical control station. It contains several indicators and controls. Each will be discussed. 

The containers for water softener and clarifiers are situated in the door of the dishwasher. The reed sensor is mounted next to the plastic casing that contains a magnet in a protective foam housing, floating on the liquid. When the level drops to a certain point, the floater activates the reed sensor, which in turn directly operates an indicator light on the front panel. The operator of the dishwasher is then alerted that softeners and/or clarifiers need to be refilled. 

Turn the stirrer knob so that the mark on the knob is about half of the way between the SLOW and FAST markings on the front panel. That s just a suggestion. I don t have any compelling reasons for it. 

The front panel control varies the duty cycle, the time the controller is full on, to the time the controller is full off. If the flask, contents, and heating mantle are substantial, it takes a long time for them to warm up and cool down. A setup like that would have a large thermal lag. With small setups (approx. 50 ml. or so), there is a small thermal lag and very wild temperature fluctuations can occur. Also, operating a heating mantle this way is just like repeatedly plugging and unplugging it directly into the wall socket. There are not many devices that easily take that kind of treatment. 

A case, such as an attache case or briefcase, has a cover panel, back panel, front panel, top panel, bottom panel opposing tabs and opposing side panels. It is made from a unitary sheet of expanded PE, which is produced by encapsulating a thermoplastic blowing agent... 

FIGURE 11.12 Hypothetical displacement separation of a three-component mixture containing two trace components loaded at 0.1 mg each and a major component loaded at 20mg. Panel a, main component band and displacer front panel b, peaks of the impurities panel c, peak of the second component under analytical (linear elution) conditions. (Reprinted with permission from Elsevier from Viscomi, G.C. et ah, J. Chromatogr., 440, 157, 1988. Copyright.)... 

Wood finishes (doors, front panels of furniture, lamination and lacquer finishes)... 

The front panel of the controller has two four-digit thumbwheel switches and two lighted pushbutton switches. The thumbwheels determine flow rate (ml/min) and volume to be delivered (ml). One pushbutton switch initiates the pump-refill operation. The other starts the injection, or stops an injection in progress. After power-up or reset, the microprocessor initializes itself and sets up the timing module and serial ports. It then jumps into a looping program that scans the two pushbutton switches and the... 

Autotransformers are also widely used in laboratories. They allow the temperature to he controlled within a narrower interval. Let us consider a type JIATP-1 autotransformer (Fig. 12). Its front panel has six terminals. It is connected to 220-V mains via terminals 1 and 3,... 

Two important parts of the electronics for a TCD are not showr in Figure 5.8. In practice the four cells of a detector rarely match. A control is usually provided so that the output voltage can be nulled before a chromatogram is run. This is usually done with variable resistors connected in the bridge. Often there are two controls on the front panel "Fine" and "Coarse" Balance. Another necessary control, at least when an integrator is not used, is an attenuator switch. This reduces the response on the recorder by various amounts so that the larger peaks can be kept... 

Areas of high microwave flux are checked with a Pelco 36140 microwave bulb array (Ted Pella). Specimens are not placed in areas indicated by illuminated bulbs. Vials containing the specimens are placed in a cold tap water bath (50 ml) that is preheated to the required temperature. The temperature is regulated by placing the microwave temperature probe into a vial of the same solution that is present in the specimen vial. The built-in temperature probe displays the specimen temperature on the oven front panel. The wire that attaches the probe to the oven is submerged in the water to decrease the antenna effect. An additional 400 ml of static water load is placed in the oven at an optimal position determined with the microwave bulb array. This water is changed between every step. 

The second set-up concept from Microinnova, the Lab Experiment Toolbox , has some minor differences from the first concept. It was designed to speed up process development and reduce the time to market of chemicals or compounding products (Figure 4.25) [77]. A modular toolbox has been developed for laboratory-scale experiments. Small tube connections are used to connect various unit operation devices to each other. Process control and user interface are based on Fieldpoint and LabView or Microinnova Process Control. The integration of the sensors into the system is different to the previous concept. The Fieldpoint unit has a front panel, where sensors can be added on a plug-and-play basis. All experimental data are stored in spreadsheets, which can be transferred to common spreadsheet... 

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