Instrument computerized control

Monitoring by Electromechanical Instrumentation. According to basic engineering principles, no process can be conducted safely and effectively unless instantaneous information is available about its conditions. AH sterilizers are equipped with gauges, sensors (qv), and timers for the measurement of the various critical process parameters. More and more sterilizers are equipped with computerized control to eliminate the possibiUty of human error. However, electromechanical instmmentation is subject to random breakdowns or drifts from caUbrated settings and requires regular preventive maintenance procedures. 

Fiatron Finlite 600 Laboratory process control and pilot plant instrument computerized Colorimeter... 

The calibration procedures adopted on-site must be agreed on with the customer and conform to recognized industry instrument calibration standards and the supplier s instructions. These procedures must be applied to all in-line instrumentation, loop instrumentation, local controllers, analyzers, and so on. Where the control and monitoring instrumentation is integrated with a computerized control system and where factory tests have been carried out, the installation calibration procedure should be agreed on with the customer. 

Loop testing of instrumentation and any associated computerized control system should encompass the interfaces with electrical equipment (via the electrical and instrumentation interface panel) and its related operation. Loop testing must not be carried out on electroific equipment until an adequate warm-up period has elapsed. Where possible, equipment should be energized for at least 24 h prior to testing. 

For electronic loops, check polarities, measure the loop impedance, and make the necessary compensating adjustments. The compensating adjustments on smart instruments can be made using either a handheld terminal or direcdy at the instrument. Smart instruments, if supported, can also be adjusted using an instrument configuration page on a computerized control system. 

On completion of installation, all documentation associated with the installation, calibration, and testing of the field instrumentation, along with any associated computerized control system documentation, should be collated by the project manager/engineer ready for IQ. Most of this documentation will be in the pre- as-built condition at this stage of the project and will, therefore, contain site (red line) markups. 

OQ verifies that the control and monitoring instrumentation, as integrated with the process equipment and any associated computerized control system, meets the operational and functional requirements defined in the instrument application design documentation and/or computerized control system User Requirements Specification (URS). PQ verifies that the control and monitoring instrumentation, as integrated with the process equipment and any associated computerized control system, meets the operational and functional requirements defined in the instrument application design documentation and/or computerized control system URS, and prodnces pharmaceutical product consistently to specification. ... 

Periodic reviews of the mannfacturing process, inclnding the control and monitoring instmmen-tation and any associated computerized control system, mnst take place from the time it is handed over to a site nntil it is replaced and/or decommissioned, in order to verify that it continnes to be capable of prodncing qnality product to specification. The pnrpose of a periodic review, with regard to control and monitoring instrumentation, is to verify that it has been maintained in a validatable condition. 

Instrumentation and control systems as well as degree of computerization have been established based on preliminary instrument engineering. 

M + H] and cluster ions such as [M + NH4]. Fig. 7 shows El and Cl (ammonia) spectra of a phenolic antioxidant. Note that the highest mass ion in the El spectrum is m/z 368, that which is hypothesized to be the molecular ion. The ammonia Cl spectrum shows a higher mass ion at m/z 386— which is 18 mass units higher ([M + NH4]+) and confirms the molecular weight of this analyte to be 368. Note that Cl is a thermodynamically controlled rather than a kinetically controlled process, which can result in significant variability in Cl spectra over time and between instruments. Computerized libraries of Cl mass spectra therefore have very limited utility. 

Figure 20-24 is a block diagram of the computerized control and dala-acquisition system of a triple quadrupole mass spectrometer. This figure shows two features encountered in any modern instrument. I hc first is a computer that serves as the main instrument controller. The operator communicates via a keyboard with the spectrometer by selening operating parameters and conditions via easy-to-use interactive software. The computer also controls the programs responsible for data manipulations and output. The second rcature common to almost all instruments is a set of microprocessors (often as many as six) that are responsible for specific aspects of instrument control and the transmission of information between the computer and spectrometer. 

As more complex operations, such as catalytic cracking and reforming were introduced, more complex instrumentation and controls were needed to operate the plants safely and economically. Pneumatic units replaced manual controllers as operations became more complex. These were subsequently replaced by electronic controllers, then by programmed smart controllers, and eventually by computerized systems. Each evolution required that operators, instrument technicians, and analyzer technicians have more and more technical training to understand process operations and perform their Job safely and profitably. A gradual evolutionary process occurred and many employees evolved into technicians. They were no longer just blue collar workers. 

The precision of physicochemical measiu ements by GC relies on the ability of the instrument to control and measme all parameters relating to the chromatographic process. Sources of inaccmacy include the determination of stationary phase mass, column temperature and its gradients, flow rate and stability, pressme drop along the column, dead space in the system, etc. Sophisticated computerized equipment allows precise measurement and control of all these operating parameters. 

Presenting nearly 50% new and revised material, this thoroughly updated edition incorporates the latest advances in instrumentation, computerization, calibration, and method development in NIR spectroscopy. The book underscores current trends in sample preparation, calibration transfer, process control, data analysis, and commercial NIR instrumentation. New chapters highlight novel applications including the analysis of agro-forestry products, polymers, blood, and control serum. They also cover NIR spectra, process analytical technologies (PAT), quantitative and qualitative analyses for nutraceuticals, NIR photography uses in medicine, and counterfeit detection methods for various applications. 

The character and the degree of automation in chemical control may have been covered in the above treatment of semi-automatic or completely automatic, and of discontinuous or continuous analysis, but something more should be said about the means by which automation proper has been performed in recent times. Whereas in the past automated analysis involved the use of merely, mechanical robots, to-day s automation is preferably based on computerization in a way which can best be explained with a few specific examples. Adjustment knobs have been increasingly replaced with push-buttons that activate an enclosed fully dedicated microcomputer or microprocessor in line with the measuring instrument the term microcomputer is applicable if, apart from the microprocessor as the central processing unit (CPU), it contains additional, albeit limited, memory (e.g., 4K), control logics and input and output lines, by means of which it can act as satellite of a larger computer system (e.g., in laboratory computerization) if not enclosed, the microcomputer is called on-line. 

A computerized laboratory can utilize a software package called a laboratory information and management system (LIMS) to carry out or control all of these requirements provided that computerized instrumentation, computer terminals, printers and plotters, disk drives etc. are linked together in a local... 

Computers were first used in laboratories to calculate results and generate reports, often from an individual instrument. As automated analysers were developed, so the level of computerization increased and computers now play a major role in the modem laboratory. They are associated with both the analytical and organizational aspects and the term Laboratory Information Management System (LIMS) is often used to describe this overall function. Such systems are available that link the various operations associated with the production of a validated test result, from the receipt of the sample to the electronic transmission of the report to the initiator of the request, who may be at a site removed from the laboratory. Other uses include stock control, human resource management and budgets. 

In 1978, I became Director of Research at the LGC. In addition to responsibilities for automation and computerization, my division was responsible for analytical instrumentation, for example NMR and inductively coupled plasmas. As part of this job, I collaborated with the UK s Department of Industry sponsorship scheme promoting the development of analytical instrumentation. Thus, I was actively involved in vetting proposals, modifying them and then controlling them to ensure a good return on investment. At this time, the introduction and availability of microprocessors had become an extremely taxing and topical area of interest. During my years at the LGC, I tackled all... 

Analytical procedure is a systems problem and the samphng, pretreatment, measurement, data collection and reduction, and final reporting all have to be considered in a fiilly automatic approach. Computerization is often considered to he synonymous with automation but, although microprocessor technology is certainly changing the face of automatic instrumentation and influences both the control aspects and the data reduction, computerization is only a part of automation. Computers should simply be considered as tools of the trade within the area of automation. 

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