Instrumentation indications

These assemblies are fitted with switching devices (breakers, switches, fuse switches and contactors etc.) and control and measuring instruments, indicating, regtilating and protective devices etc. to transform the assemblies into composite units, called control centres to perform a number of functions in the field of distribution and control of electrical power. Some of these functions may be one or more of the following ... 

Compatibility with Personnel Expectations Compatibility refers to the degree of similarity between the direction of physical movement of a control or an instrument indicator and the worker s expectations. Many errors are due to the fact that the operation of the controls or the layout of the displays is incompatible with population stereotypes. For instance, on a control panel it is customary to increase the value of a parameter by turning the appropriate switch clockwise and reduce its value by turning it coimterclockwise. (Note that this stereotype is the opposite for controls which control flow directly, e.g., valves.) If such a stereotype is violated, errors may occur. Although such errors may be recoverable in the short run, under the stress of a process transient they may lead to serious consequences. 

Population Stereotype Expectations held by a particular population with regard to the expected movement of a control or instrument indicator and the results or implications of this movement... 

Anzeige, /. information indication (of an instrument) reading notice, report, circular, advertisement, dispatch sign, mark, -instrument, n. indicating instrument, indicator, anzeigen, v.t. inform, announce, advertise indicate show. — angezeigt, p.a. advisable, proper, fit,... 

If the instrument indicates current surge in an air-free system, it generally implies hydrogen sulfide contamination, but the galvanic probe is usually best suited to detect corrosion influenced by oxygen contamination. 

The gas to be tested may be drawn or forced at the rate of a few cubic centimeters per minute through the test chamber, which in present models has a volume of about 4 ml., or it may be introduced after evacuating the test chamber. The instrument indicates correctly the magnetic susceptibility of the gas in the test chamber within a few seconds the main delay in reading the instrument is caused by the time required to introduce the gas. 

Reaction experiments were performed at the substrate to catalyst ratios between 250 and 5000 (Table 1). The immobilized catalyst showed a rather constant values of TOP and enantioselectivity in spite of the increase in the S/C ratio, even though these values were slightly lower than those of the homogeneous Ru-BINAP catalyst. After the reaction, the Ru content in the reaction mixture was measured by ICP-AES and was found to be under 2 ppm, the detecting limit of the instrument, indicating the at Ru metal didn t leach significantly during the reaction. These results show that the immobilized Ru-BINAP catalyst had stable activity and enantioselectivity and that the Ru metal complex formed a stable species on the alumina support. 

Thermal Emission Spectrometer) instrument indicated the metallic nature of the rock [340]. Observations made with the panoramic camera and the microscopic image revealed that the surface of the rock is covered with pits interpreted as regmaglypts and indicate the presence of a coating on the surface. The a-Particle-X-ray spectrometer (APXS) and the Mossbauer spectrometer were used to investigate the undisturbed and the brushed surface of the rock. Based on the Ni and Ge... 

Lag time (initial response time), the interval between the time to, when a step change (increase or decrease) in pollutant concentration is made, and the time t when the instrument indicates a response equal to twice the noise ... 

Fall time, t/. the interval between the time the instrument indicates -100% of the step decrease in pollutant concentration (t oo) and the lag time (t,) ... 

A signal measured by the instrument indicates absorbance of an element in the flame. This absorption depends on the number of ground state atoms N0 in the optical path. This is where comparison with the Beer—Lambert law ends (e is not calculated). Measurements are made by comparing the unknown to standard solutions. 

Measurements of the fiber length using a Kajaani instrument indicate that y irradiation does not affect the length of the fibers. The average fiber length is... 

DESCRIBE the temperature instrument indication(s) for the following circuit faults ... 

Sir, my instruments indicate that the Big Bang glow is 0.01 degrees above absolute zero. The Universe s temperature decreases as the two-thirds power of time.1 That means we re about 1014 years into the future ... 

Verify the reliability of the instruments (especially pressure gauges) be prudent on instrument indications especially if "plugging" materials are handled ... 

Moulded-in busbars 6 Isolator blades with moving contacts 7 Hinged front door 8 Door interlocked with isolator 9 Flameproof window for instruments, indicator lights and operation counter 10 Flameproof windows for visual isolation 11 Fault reset and/or earth fault test push-buttons under covers 12 Static protection unit ... 

The technical specifications identified and described by most of the manufacturers of absorption photometers for medical use include wavelength accuracy, spectral half-width of spectral radiation flux at the detector, photometric accuracy, percentage of wavelength integrated, false radiation, and photometric short-time repeatability. As discussed previously [2], the Instrumental Performance Validation Procedures, issued by serious manufacturers of analytical instruments, indicate the methods and the reference materials required to test and to maintain optimum spectrometer performance in daily routine analysis. 

In addition to alarms, printouts, and instrument indications, the human senses are valuable indicators of a potential emergency. These shotild also be included as appropriate. These are... 

The city s mechanics claim that a standard antifreeze formulation was used and this formulation was mixed with water in a proportion which their density instrument indicated was good to -40"F. We have obtained samples of both the formulation used and the actual antifreeze mixture found in one of their trucks. Our job will be to see if the mixture found in the truck really does have density and a composition indicating that it would, in fact, protect the truck engines. 

Option 3 Costs for Instrumentation of Particular Types of Equipment Table 16.15 fists typical DCS (control loops, C alarms. A and transmitters, T) and the types of field instruments (indicators, I, and relief valves, R) for different types of equipment and their FOB cost. For this list, we give an estimate of the installed instrument cost in Table 16.15. These results are reasonably consistent with the previous two methods. 

Rickenbacker Industrial Boiler Demonstration. In February, March, and April 1981, the EPA, through its contractor, PEDCo Environmental, Inc., conducted adipic acid-enhanced limestone scrubber tests on an industrial-sized system. The testing was carried out at the Rickenbacker Air Force Base on a Research-Cottrell/Bahco system rated at 55,000 scfm, or about 27 MW equivalent. The tests, conducted with certified instrumentation, indicated an SO2 removal efficiency increase from 55 percent without adipic acid, to 90 to 95 percent with adipic acid. This improvement was achieved at a scrubber inlet pH of 5.0 and adipic acid concentrations of between 2,000 and 2,500 ppm. More complete data will be reported separately by others. 

Specimen 2 (Fig. 2) is an example of a more problematic failure surface to characterize visuEilly. The visual observations were fairly consistent (= 75 %), except for E (10 %). However, the laser-scan instrument indicated far less wood failure (44 %) at the 40 pm-tolerance levels. Upon closer examination, the failure surface contmned tall, narrow ridges of wood fragments that pulled out of the opposing adherend with regions of exposed adhesive in-between. The laser-scan instrument was sensitive enough to detect these narrow adhesive regions, which may not have been readily apparent in visual observations. 

Specimen 3 (Fig. 2) was also a problematic surface to evaluate visually even though the regions of adhesive and wood failure were more obvious than those of specimen 2. Despite this, the visual determinations of wood failure still varied widely (30-95 %). The laser-scan instrument indicated 52 % wood failure at the 40 pm-tolerance levels and 37 % wood failure at the 60 pm-tolerance levels. 

A misleading level indication due to oil accumulation in the column base caused severe operating problems in many aqueous services. In several cases, liquid level in amine towers rose above the bottom feed inlet and caused column flooding, while the level instrument indicated normal level (238). In another case (238), a glycol regenerator performed poorly when the liquid level in a kettle draw compartment rose above the overflow weir, while the level instrument indicated normal level (238). 

False signals When an instrument indicates an unexpected reading, it should be adequately checked rather than disbelieved, as it may indicate an unexpected process condition. It is always worth verifying this reading by looking at other instruments. In one incident (210), column instrument readings were overlooked for several hours after the bottom temperature controller failed. Eventually, flammable oil spilled from the reflux drum. 

Figure 13.8 A faulty level sensor can cause overheating, (a) A nudfunctioning level sensor mistakenly senses a high level. It opens bottom valve. (6) Level drops and uncovers temperature sensor. If vapor temperature is lower, the controller will 1 for more heat, (c) Level is low, and bottom sump liquid is overheating, hut instruments indicate normal level and normal temperature.

For the instructor) Demonstrate to students in the laboratory the principal components of an NMR instrument. Indicate the steps taken in tuning the instmment. 

Remove specimen adjust micrometer so that the instrument indication of capacitance is returned to its original value C. Record the dissipation factor value D. Record the micrometer reading mj. 

Combustible gas testing instruments indicate the volume percent of combustible gas in air expressed in poeent of the lower explosive limit (% LEL). The LEL is the lowest percentage of die substance in air which will bum or explode when ignited. Most hydrocarbons will flash at lower hydrocarbon concentrations but will not genoate enough heat to allow burning to continue. 

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