Status alarms

Status alarms. An expected or normal state is specified for the discrete value. A status alarm is generated when the discrete value is other than its expected or normal state. 

Another serious distraction to a process operator is the multiple alarm event, where a single event within the process results in iTuuti-ple alarms. When the operator must individually acknowledge each alarm, considerable time can be lost in silencing the obnoxious annunciator before the real problem is addressed. Air-handling systems are especially vulnerable to this, where any fluctuation in pressure (for example, resulting from a blower trip) can cause a number of pressure alarms to occur. Point alarms (high alarms, low alarms, status alarms, etc.) are especially vulnerable to the multiple alarm event. This can be addressed in one of two ways ... 

Point alarms (high alarms, low alarms, status alarms, etc.) are especially vulnerable to the multiple-alarm event. This can be addressed in one of two ways ... 

Earth fault protection, settings, status, alarms. 

Type 1 Alarm Equipment status alarm. Equipment status indicates, for example, whether a pump is on or off, or whether a motor is running or stopped. 

Finally we had realized that there is no document available which allows the operator simple verification of software or to adapt certain parts of the software to local needs. In example the procedures to change date and time in the status window, to change the denomination of sensors in the status-, alarm- and scram windows or to access the pulse number or the kWh value in case of necessary changes, all this has to be individually asked for. This is a time consuming and unnecessary burden for both the operator and the supplier. In fig.4 there is a summary of instrument related problems since summer 1992. 

This chapter has only scratched the surface of the multitude of databases and data reviews that are now available. For instance, more than 100 materials databases of many kinds are listed by Wawrousek et al. (1989), in an article published by one of the major repositories of such databases. More and more of them are accessible via the internet. The most comprehensive recent overview of Electronic access to factual materials information the state of the art is by Westbrook et al. (1995), This highly informative essay includes a taxonomy of materials information , focusing on the many different property considerations and property types which an investigator can be concerned with. Special attention is paid to mechanical properties. The authors focus also on the quality and relutbility of data, quality of source, reproducibility, evaluation status, etc., all come into this, and alarmingly. 

Signals for internal defects and external status and alarms... 

Because of these solutions, important technical data can be transferred from local instrumentation (control system) through data-based controllers to a control station with computers. The operator may use the many variations that the software data system provides. Technical data operation may be digital off/on messages such as the status of operation and the performance of alarms or analog measurements such as temperature, humidity, pressure, velocity, energy usage, etc. 

Detect the condition of and operate filters and dust-cleaning devices. Receive and register status and alarm messages. 

Representational layout of control panels. Where the physical location of items is important, for example, area displays in fire control systems, the layout of the displays on a control panel should reflect the geographical layout of the plant. In other cases a functional arrangement of the elements of the process plant will be appropriate, for example, when monitoring the status of the system via an alarm panel. 

Review of alarm logs The alarm log, gas alarm start times and time of return to green status were reviewed. 

The exhaust duct of each ventilated containment cabinet must be fitted with an adjustable low flow sensor. Audible and visible alarms must be located near the cabinet, and the silence switch should energize an indicator at the status board. These are local alarms which should not automatically trigger a call for emergency response personnel. 

The alarm systems should have a philosophy that relates to the input data - number, types, degree of alarm, and displays and priorities. The information load on the operator has to be constantly taken into consideration, e.g., the distinction between alarms and status signals versus operator action that needs to be initiated. 

Process alarms should be arranged to provide a major common alarm that is supplemented by an individual indicator, e g., a master alarm should be provided to indicate the status of the entire subsystem components. Multiple simultaneous alarms that can overload the senses of an operator should be avoided. 

In conventional expert systems, the facts and knowledge upon which the inference is based are static. In the industrial application, the facts or process measurements are dynamic. In an industrial application there may be several thousand measurements and alarms which may significantly change in value or status in a few minutes. 

Data transfers, in floating point engineering units or in status states, are requested by the expert system. Thus the distributed system does not transmit all measurements and alarms on a fixed scan basis, but rather the process data are accessed as required for inference. In a sense, the expert system is acting like an expert operator, who focuses attention or scans the process operation selectively, using expertise to determine specific areas of attention. 

In addition to the abbreviated LCD display on the fire alarm panel, an annunciator should be provided to graphically display facility conditions in all areas. Often this annunciator is an additional panel provided with the fire alarm system, which contains a graphic display or representation of the plant or area being monitored as well as illumination capabilities which identify the status of all monitored plant areas. 

Chapter 6 discussed signaling pheromones that allow discrimination, recognition, and broadcasting dominance and territorial status. This chapter explores the role of pheromones and other odors in reproduction, alarm, trail following, and in connection with food. Some evolutionary considerations conclude the discussion of signaling pheromones. 

Automation equipment at the metering sites generate production volume information, indicate alarm and other equipment status, and provide some control capability. This equipment is connected to remote terminal units (RTU) at optimum points within the field by individual wire pairs of buried cable. The RTU s store the information generated and, on request from the computer, transmit it to the computer center by means of microwave or wireline. RTU s also receive messages from the computer for transmittal to appropriate equipment for execution. 

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