182 R. Wetherington et al. 10 9 8 7 6 5 4 3 2 1 0 05/01 16 14 12 10 8 6 4 2 05/02 05/03 05/04 TIME (UTC) Current (ADC counts) Current (ADC counts) 05/05 05/06 05/07 05/01 05/02 05/03 05/04 TIME (UTC) 05/05 05/06 05/07 Phase A Phase B Phase C Ground ×108 ×107 REDC Collection Site ADC Counts REDC Collection Site ADC Counts Fig. 15.9 Seven-day RMS values phones every morning at 8 AM. This provided an easy means of checking on the systems operating state. Figure 15.9 shows a typical seven-day plot. The time stamps that were included in the data file names were also analyzed and used to detect when a sampling error occurred. 15.5 Conclusions ORNL has designed and deployed three high-speed data MINOS collection systems that utilize low-cost consumer grade audio recording adapters for gathering field data. Each system provides four channels of sensor data that are sampled at 96 ksamples/s each. Data is gathered continuously. The systems have been operating since August 2018 and produce approximately 4 Terabytes of data per month per system. The data quality is considered to be very good for conducting analysis of operational features in the data. A number of actions were required to prepare this technology for deployment including characterization of the device’s frequency response, software development of the main data acquisition process, verification that the implementation would not lose samples, taking independent field measurements that were then used to determine calibration coefficients, and the development of simple operational validators that would produce simple plots that could be reviewed to verify proper system operation. While there are other approaches to achieving high-speed data sampling, the use of consumer audio adapters offers a very cost effective solution if the user is prepared to invest some effort up front to develop test and qualify the system for use. This may not be a cost-effective solution for a single deployment, but it can very cost effective when multiple units and channels are fielded.
RkJQdWJsaXNoZXIy MTMzNzEzMQ==