Figure 1-3 Trend Log Collection - Emerson Daniel 3818 Maintenance And Troubleshooting Manual

Section 1: Routine maintenance
January 2018
Trend maintenance log collection
Merging the results of two or more Maintenance logs into a single file, allows you to build a
historical database of the meter's performance. Trending the logs indicates changes from the
original installation of the meter over time. Looking at a single inspection report, that is either
collected monthly or quarterly, will only give you an indication of the meter's current health.

Figure 1-3 Trend log collection

This is important since many diagnostics change slowly over time. Trending the maintenance
logs helps identify these changes and makes problems much more obvious than merely viewing
a single inspection report. The Trending feature is integral to Daniel MeterLink which allows all
important parameters to be trended. Daniel MeterLink supports trending files in a Microsoft®
Excel® workbook from multiple 3818 meter maintenance logs. Some parameters like gain,
signal level, and noise level may show a shift over time which can be useful in detecting changes
in the meter and the installation.
Maintenance logs to be trended must all have matching column headings. This means the logs
must be in the same units (i.e. U.S. Customary or Metric), must have the same pressure type (i.e.
gage or absolute), and must have the same time base (1/second, 1/minute, 1/hour, 1/day). If
not, an error message will be displayed stating the column headings do not match and the file
will not be added to the Workbook to trend list.
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Maintenance and Troubleshooting Manual
Maintenance logs and reports
3-9000-772 Rev B