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Percent Capacity Alarm Algorithm
Shelf Current > (# inverters
-
# redundant
-
inverters)* inverter
-
capacity * (% of capacity) for
more than 2 seconds.
Alarm Settings Associated with Inverters
14
Settings are for 10 A
ac
inverters. Settings for 5 A
ac
inverters are in parentheses.
Hi Output Current RMS Alarm
Range 8.0 to 15.0 A
ac
(4 to 7.5 A
ac
)
Factory set to 12.5 A
ac
(6.25 A
ac
)
Hi Output Current RMS Alarm
Range 4.0 to 7.5 A
ac
(4.0 to 3.75 A
ac
)
Factory set to 6.0 A
ac
(3.0 A
ac
)
Hi Output Current Peak Alarm:
Range 18.0 to 28.0 A
ac
(9.0 to 14.0 A
ac
)
Factory set to 28.0 A
ac
(14.0 A
ac
)
Hi Output Current Peak Alarm
Range 9.0 to 14.0 A
ac
(4.5 to 7.0 A
ac
)
Factory set to 14.0 A
ac
(7.0 A
ac
)
Hi Crest Factor Alarm (Peak/RMS)
Range 0.00 to 5.00
Factory set to 0.00 (disabled).
Crest Factor is a ratio between Peak and RMS current. A purely resistive load powered by a
sine wave voltage has a crest factor of 1.414. Nonlinear loads, such as electronics without
power factor correction, will have crest factors higher than 1.414.
Each inverter meters its crest factor. The metered crest factor can be displayed through
the System Controller.
To enable this feature change the setpoint to the desired value between >0 and 5.0. Be
certain to display and note the reported crest factor through the System Controller prior
to enabling this alarm.
Crest factor >3.0 indicates a very nonlinear load.
To avoid nuisance alarms leave the crest factor disabled or set the threshold to >1.5 x the
measured crest factor. There is no practical reason to set the Crest Factor alarm at a value
below 2.5.
Shelf Number Setting
Range 1 through 4.
Factory set to 4.
13
Distribution Disconnect Module, Distribution Monitor, and System Controller features refer to a single shelf. The described features are duplicated and are
independent of each other in each shelf of multiple shelf systems.
14
System will indicate an alarm after the set threshold has been exceeded for 5 seconds.
