PMI Eagle 220, Руководство пользователя

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What the Eagle™ Records
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The Eagle is initialized with a list of potential nominal voltages
(such as 120V, 240V, etc.), with low and high voltage thresholds
for each. The actual nominal is picked by the Eagle during the
two-minute countdown. The average voltage during the
countdown is compared to each of the nominal voltages; the
closest one becomes the nominal voltage for the entire recording
session.
There are five standard nominal voltages in the software setup
(120V, 208V, 240V, 277V, and 480V), and two custom nominal
voltages. The custom nominal voltages can be set to any voltage.
It is possible to enable and disable the standard and custom
nominal voltages. For example, if you wanted to force the Eagle
to use 230V as the nominal, the standard nominal voltages should
be disabled, and both custom nominal voltages set to 230V. If the
standard nominal voltages were not disabled, there would be a
chance for the Eagle to pick 240V during the two-minute
countdown, if the line voltage happened to be running closer to
240V than 230V at that time.
The nominal voltage is chosen by the Eagle separately for each
voltage channel. There are separate high and low thresholds for
each of the seven nominal voltages. The applicable thresholds
are used once a nominal voltage is selected by the Eagle after the
two-minute countdown. Voltage channels are handled separately;
there is a complete set of nominal voltages and thresholds for
each. The Eagle will automatically select the correct nominal and
threshold voltages for each channel.
The last abnormal voltage parameter is a trigger duration, in
seconds. This specifies how many seconds in a row the voltage
must exceed the threshold voltage before the abnormal voltage
record is triggered. At the end of each second during the
recording session, the Eagle compares the one-second average
voltage with the nominal and the low and high thresholds. Each
threshold actually creates two trip points, one above the nominal
and one below. For example, consider a setup where the nominal
is 120V, the low threshold is 6V, and the high 12V. The low trip
points become 120±6, or 114V and 126V. The high trip points are
120±12, or 108V and 132V. If the one-second average voltage