ACR Electronics PowerWatch, Справочное руководство

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PowerWatch Operating Overview
52
2007 ACR Systems Inc.
Events
Sag events
Frequency events
Impulse events
Outage events
Loss of Synchronization events
Ó 2007 , ACR Systems Inc.
5.2.1.6 Outage events
Outage Events
When PowerWatch records a sag of below 70Vrms for longer than a second it
displays the event as an outage. The VDR will go into self-powered mode
(battery) and will sample the voltage every eight seconds. As a result, the
shortest outage it will record will be eight seconds. When the power is
reapplied to PowerWatch, the VDR will not detect it immediately, but will wait
until the next eight-second sample before returning to the line powered
operational mode. This delay will prevent contact bounce being reported as an
event when PowerWatch is plugged into a standard electrical outlet.
Since PowerWatch's eight-second clock is not synchronized with outages, it
can sometimes report an outage as 16 seconds when in fact the outage only
lasted for slightly over one second. An example of when this would happen is
if a sag below 70Vrms occurred 6.9 seconds into an eight-second period. At
the 7.9-second point, PowerWatch would change to self powered mode and
report a minimum outage of eight seconds. If then, at the 8.1-second point,
power was restored, the VDR would not sample again until the 16-second
point.
See also:
Events
Impulse events
Sag events
Surge events
Frequency events
Loss of Synchronization events
Ó 2007
, ACR Systems Inc.
5.2.1.7 Frequency events
Frequency Events