Process computer rooms

The distributed control system (DCS) hardware areas are often referred to as "process computer rooms." I/O Rooms contain the incoming and outgoing wiring, cables and data highway links, and often small transformers and other related electrical equipment. Often, additional space is needed for a master process engineering computer terminal/work station for process control system changes and for critical safety instrumented systems (SIS) for interlocks and emergency shutdowns. 

To remove impurities which may be harmful to a process, e.g. fine dust in a computer room, bacteria in a pharmaceutical packing room... 

Computer rooms considered in this section are those installations of substantial size and importance providing primarily data processing and network support service for multiple large process units or for an entire plant site. These installations are typically much larger than ones for an individual processing facility s dedicated process control computer. 

Instrumentation will include field instruments used in the manufacturing process and other instruments assoeiated with special tasks, such as that of monitoring laboratory or computer room environmental eonditions. The accessibility of instruments must be such as to permit their eleaning and maintenanee. Siting is also important, and instruments should be installed as close to the point of measurement as possible. The placement of flowmeters in piping dead-legs should be avoided. Careful consideration should also be given to the appropriate position of other instruments sueh as thermometers and thermocouples so that they, too, can fulfill their measurement and eontrol functions. Construction materials that come into direct contact with the pharmaceutical or healthcare production process stream must not contaminate or affect the manufactured product in any way. Instrument lubricants and coolants must not come into contact with in-process product or equipment. The reliability of instruments should also be considered for instance, a pressure transmitter that uses atmospheric pressure as its reference may suffer from poor reliability. A draft calibration schedule may also be prepared. 

IPCs mnst contend with a range of conditions not normally encountered with the more common usage of PC technology, i.e., in the office, computer room, or process control room environments. IPCs must deal with conditions such as ... 

The plant is controlled by a process computer (ABB-Hartmann and Braun) and equipped with numerous data-collecting instruments. Surveillance is carried out by continuous analysis of the room air as well as by explosion-limit controls. The pyrolysis gas is analyzed automatically by a gas chromatograph. All data obtained are registered to enable calculation of energy and mass balances. Some basic components are continuously monitored by infrared spectroscopy, i.e. ethylene in the pyrolysis gas, sulphur dioxide and oxygen in the exhaust gas. 

Fluoropolymers. Melt processable fluoropolymers such as Teflon FEP, Tefzel ETFE, poly(vinylidene fluoride) (Kynar), and ethylene-chlorotrifluoroethylene copolymer (Halar) are suitable for wire insulation in special applications because they combine good physical properties with low flammability. They are used for instrumentation cable in process-control rooms, as well as for computer and aircraft wiring and in military applications. The... 

The central control building contains the control room, the switching, control and closed-loop control systems, the reactor protection systems, the emergency power supply, and further installations such as process computers, air-conditioning and ventilation systems. 

Rod position is sensed by a series of sealed glass reed swifches contained within a tube inside the drive piston. Two switches are spaced every 3 in. (76 mm) with each of the dual switches feeding a separate channel. These signals are multiplexed inside the containment and transmitted to the control room. The rod position information function decodes these data and makes them available to other parts of the RC I function, to the process computer and to the operator. The detection of an invalid inpuf caused by a failed reed switch is indicated. The status of the scram valves and accumulators on the hydraulic control unit is monitored, and these data are available to the operator and the computer. 

Several types of automation and control systems have been used and all have performed successfully. Thus the WER-440 Is fully developed to be fitted with state-of-the-art Instrumentation, automation and control system technology covering several operating modes. This includes advanced control room layouts featuring process computers and colour CRT-dlsplays for monitoring and control duties. 

Flow rate variations are tolerable due to the variability of the process. Indeed, it is preferable to consider the process diagram flow specifications as indicative values, rather than set specifications. When compared to design specifications, control room printouts indicate that input flow rates are not set. Also, production reports from the plant show that the total pulp output may vary considerably from day to day. In this respect, the validation model has to be flexible enough to be reconciled with different sets of data sampled at different points in time. For this reason, measured flow rate variables were often specified with larger inaccuracies than other variables. Table 2, compares global mass balances for the entire process, computed with raw data to the... 

With this technology the dialogue between the human operator in the control room and the process events in his charge are supported and guided by the process computer (Fig. 12). The necessary safety functions are automatically performed by subordinated systems. The man in charge still makes the operational decisions, but the computer so prepares the requisite information as to present him with clear-cut conditions on which he can decide and avoid overburdening him with too much information. In this way he will not be put under too heavy a strain, so that he is unlikely to initiate wrong interventions even in critical phases of plant operation. 

GENERAL CONSIDERATIONS Cooling Towers and Legionnaires Disease Elevator Machine Rooms Energy Conservation Equipment Maintenance Equipment Noise and Vibration Evaporative Cooling Fire and Smoke Control Dampers Outdoor Air Perimeter Heating Process Loads Room Air Motion OCCUPANCIES Clean Rooms Computer Rooms Offices Test Cells... 

II. 13. Certain areas of the plant tend to be natural centres of convergence for eqrripment or wiring of various levels (categories) of importance to safety. Examples of such centres may be containment penetrations, motor control centres, cable spreading rooms, equipment rooms, the control rooms and the plant process computers. Appropriate measures to avoid common cause failtrres should be takerr, as far as practicable, in such locatiorrs. 

Computer simulations of the photosynthetic reaction center exhibit slow dynamics (5ps) at high temperatures (500K). This time scale can be extrapolated to lOOps at room temperature. This value is in principle too far away from the microsecond time regime of the considered electron transfer process to be relevant. But a much stronger non-Arrhenius like temperature dependency can change the situation. We expect to clarify this point by analyzing the slow process at several temperatures to improve on the extrapolation of the time constant of the slow process at room temperature. 

Synthetic fibre air filter media can be used in most ahnospheric air or recirculated air filtration applications, and are particularly suited for the ventilation of offices, factories and public buildings, for air handling in hospitals, computer rooms, schools, airports, pharmaceutical and food processing plants, clean rooms and laboratories. 

Pocket filters are particularly suitable for the filtration or fine filtration of atmospheric air intake and/or recirculated air in air handling installations, including ambient air handling as well as process air intake installations. Specific applications include air handling installations for the ventilation of factories, warehouses, department stores, offices, school computer rooms, public buildings, conference or exhibition halls and laboratories, as well as for cooling-air intake filtration of gas turbines. 

In many applications, especially where process plant is concerned, the measurement information is required to be conveyed to a central point, which may be a control room manned by operators or a computer which carries out the control functions automatically. The connecting link between the various measurement points and the central control is usually a telemetry system, although in some cases the distances involved are so large that radio links need to be used. 

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