Section III
Operation
Page 3.4
BP
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3.4.1
Indicator Light
If the multicolor indicator light (LED), located in the upper part of the panel, is:
•
Green: UPS Normal – This indicates that the critical load is being powered from
the inverter. It represents a fully normal condition. With any alarm the LED will
change color to indicate a noncritical or actual alarm. When the alarm condition
is corrected, the LED will turn green again. See Paragraph 3.4.5 for more details.
•
Green/Red: NonCritical Alarm – This indicates that a noncritical alarm is
present, and that message will appear on the message screen. Check Alarm
History (Paragraph 3.4.2.2) to identify the alarm.
•
Red: Alarm Condition – When the LED turns red, a problem exists with the
UPS. Alarms such as ac input failure, low battery voltage, UPS overload,
transferred to bypass, transfer not available, battery not available and/or
retransfer inhibited may exist. Check active alarm conditions (Paragraph 3.4.2.1)
or alarm history (Paragraph 3.4.2.2) to identify the alarm.
–
AC Input Failure – The UPS input power has been disrupted or gone out of
specification limits. The system goes to battery power and the alarm sounds,
alerting the operator to a brownout or power failure. When the batteries run
down, the critical load will shut off unless steps are taken to correct the
situation or another source of input power is provided.
–
Low Battery Voltage – When the system is operating on battery power, this
condition indicates approximately five minutes remains before the UPS
system shuts down. A message screen (Section 3.4.2) displays the amount of
battery run time left. Also, the rectifier link (battery) voltage may be
monitored (See Paragraph 3.4.2.8). Shutdown occurs when the link voltage
drops to 148.5 VDC (selectable). If utility power can not be restored or an
auxiliary power source be activated, the critical load should be shut down in
an orderly procedure.
–
UPS Overload – The load on the UPS output is in excess of 105% of rated
load. If the condition exists for more than a few seconds, enough of the
critical load should be powered down or removed to make the indicator go
green. Otherwise, the UPS will shut down and/or transfer to bypass within 15
minutes.
This condition may occur when the UPS is loaded close to 100% and a large
disk drive or other motor load is started. These loads draw currents many
times their normal level for a few seconds when first started. The UPS is
designed to handle this short overload condition.
