What the Eagle™ Records
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http://www.powermonitors.com/support/calculations.pdf
. These
values are presented to the user as three traces on a graph: a
maximum, a minimum, and an average. The average trace
roughly corresponds to interval graphs as a graph from a paper
stripchart recorder. The maximum and minimum graphs,
however, are unique. Each gives the worst-case value for every
interval, with single-cycle measurement resolution.
Figure 13 – RMS Voltage and Current Interval Graph
Each Eagle has at least enough memory to record interval graphs
for about a month with a one-minute interval. When the interval
graph data fills the allotted memory, the Eagle has two options: it
can either stop recording interval graphs, or go into “wrap-around”
mode. In “wrap-around” mode, the oldest interval graph data
points are erased to make room for the new ones as they are
collected, which allows the Eagle to have the latest data at all
times. This choice is made by the user during the initialization
setup. If the “Interval Graph Overwrite” box is checked in
ProVision (“Stripchart Overwrite” in WinScan), the Eagle will go
into “wrap-around” mode as needed, otherwise it will stop interval
graph recording when memory is full. For example, if there is
memory for four weeks of interval graphs, and the Eagle is left in
the field for six weeks, then it will have either the first four weeks
or the last four weeks of interval graph data, depending on the
wrap-around setting.
Every Eagle can record interval graphs of voltage, current, real
power, reactive power, apparent power, power factor, and
harmonics magnitudes. Typically, only a few interval graphs are
needed at one time. All interval graphs share the same memory,