Data loggers

Data Logger it acquires the external plant parameter signals (e.g. load steam flow, temperature and pressure etc.) required for correlation with the AE activity. 

In addition, NDT plays an important part in industrial maintenance. During plant shutdowns for instance, many thousands of ultrasonic wall thickness measurements are taken on piping, vessels, furnace tubes etc. All these thickness readings have to go into extensive data bases, and this process is, thanks to modem computers and data loggers, ever more automated. 

Use a Fast Data Logger for critical pieces of equipment that can change states quickly, e.g., major rotating equipment where the usual one-minute data storage interval is not adequate in case of trips... 

An evaluation of the HVAC system may include limited measurements of temperature, humidity, air flow, as well as smoke tube observations. Complex investigations may require more extensive or sophisticated measurements of the same variables (e.g., repeated COj measurements taken at the same location under different operating conditions, continuous temperature and relative humidity measurements recorded with a data logger). 

Data from the installed instrumentation can be periodically recorded using either manual logging or with a microprocessor-based data logger. If the latter is selected, many of the vibration-based, microprocessor... 

User-friendly software and hardware The premise of predictive maintenance is that existing plant staff must be able to understand the operation of both the data logger and software program. Since plant staff normally have little, if any, computer or microprocessor background, the system must use simple, straightforward operation of both the data acquisition instrument and software. Complex... 

The data logger or microprocessor selected by your predictive maintenance program is critical to the success of the program. There is a wide variety of systems on the market that range from handheld overall value meters to advanced analyzers that can provide an almost unlimited amount of data. The key selection parameters for a data acquisition instrument should include the expertise required to operate, accuracy of data, type of data, and manpower required to meet the program demands. 

Some of the systems have incorporated an independent method of transferring data that eliminates the dead time altogether. These systems transfer stored data from the data logger into a battery-backed memory bypassing the RS 232 link. Using this technique, data can be transferred at more than 350,000 baud and will reduce the non-productive time to a few minutes. 

Potential data loggers are now available to undertake close interval pipeline surveys. These increasingly popular surveys, determine a pipeline s pipe-to-soil potential at nominal intervals, of as little as 1 m. Additional information is gained by the recording at each point, of both the pipe-to-soil potential with the cathodic protection system ON , together with the potential some 100-300 ms after the cathodic protection system is switched OFF . This instantaneous OFF potential being devoid of any IR drop component present in the ON potential measurement. 

The most versatile data acquisition option is a stand alone data collection unit. At Glidden we use an Elexor Data Logger (S) for this purpose. It has its own microprocessor and BASIC Interpreter and communicates with the computer via the serial port. The unit can be configured with a wide variety of signal processing options. 

The data logger can be used in background or real time mode. In background mode the data logger stores the data in it s own internal memory until the computer asks for it. In real time mode, the data logger simply responds to commands from the computer. In both cases, the data logger is controlled by a short BASIC program resident in it s own non-volatile RAM. 

In order to collect data via the serial port or A/D in background mode, the computer must initiate a multi-tasked routine. The limitation of this approach is the software overhead it introduces and the risk of data loss should the computer crash. When the data logger is used in background mode, the computer could be turned off and back on while a run is in progress with no loss of data. 

Gulton-Rustrak Quartel Data Logger - Model 58-100 with - Type K thermocouple pod-58-124... 

It is interesting to trace the development of instrument automation over the relatively brief period of the past ten to fifteen years. Early in this period, a truly automated instrument was a rare and expensive item built around a costly dedicated minicomputer. Automated data collection and analysis from any instrument which was not automated at the factory was usually accomplished by digitizing the data and storing it on a transportable media such as paper tape. These data were then delivered and fed to a timeshare system of some sort on which the data reduction program ran and which printed a report and sometimes a plot of the data. Often a considerable time delay occured between the generation and the analysis of the data. The scientist was at the mercy of the computer elite who could implement his data logger and provide the necessary computer resources to analyze his data. The process was expensive, both in time and in money. 

The water samples were analysed for pH, electrical conductivity (EC), temperature (T), dissolved oxygen (DO), redox potential (Eh), reduced iron (Fe2+) and alkalinity (dissolved inorganic carbon, DIC, as HC03") in the field. A few special water samples were collected to determine background levels of CD4, SF6 and Kr in the headspace gas. SWL and T were recorded hourly in 3 shallow (Sites H, I, R) and 3 deep (Sites J, V, W) open bores using automatic data loggers, which were downloaded biannually. 

FIGURE 7.6. DO measurement in a manhole of a sewer. A bag (1) contains a waterproof box (2) with electrical equipment, data logger and batteries for a DO-meter (4). The float (5) is anchored by a steel rod (3). 

Sensors were inserted in the prototype to monitor the temperature (National Semiconductors, LM35-DZ), humidity (Honeywell, HIH-3605-B) and total VOC concentration (FIS, SP3-AQ2) at various locations shown in Fig. 12.8-10. The data were collected by a data logger (Picolog, ADC-16) and analyzed. The temperature profiles from the preliminary test showed that poor seal between the hot and cool air streams compromised the prototype performance. Hot spots and uncontrollable temperature rise prevented further tests. This clearly showed that the complicated design is not suitable. 

The need to transport temperature-sensitive raw materials and products, such as cell line, medium, large molecule drugs, and vaccines, means that some form of control during transportation is needed. For example, a working cell bank for the production of proteins may be transported in liquid nitrogen (-196 °C) and that of protein and vaccines in dry ice (-78 °C) in order to protect the integrity of the materials. Data loggers are used to record the temperature... 

Identification of calibration procedures for temperature-monitoring equipment (thermocouples, data loggers, etc.)... 

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