Section III
Operation
Page 3.9
BP
II S, 3.00
08/96
3.4.4
Parameter Adjust Pushbuttons
These pushbuttons, labeled
,
, and
, are used with Alarm Identity/History
procedures (Paragraph 3.6.2) and to set or alter the parameters of the UPS.
3.4.5
Alarm Silence Pushbutton
Whenever an alarm condition exists, an audible alarm sounds calling attention to the
situation. The audible alarm is silenced by depressing the ALARM SILENCE pushbutton
once. A red LED indicates an active alarm condition that may require immediate action.
3.4.6
Emergency Power Off Pushbutton
To be used only for emergency conditions where instant shutdown of the UPS is
required. Depressing the EMERGENCY POWER OFF (EPO) pushbutton results in
immediate shutdown of operations, opening all UPS breakers and the DC (battery)
disconnect, the audible alarm sounds and all power to the critical load is shut off. Once the
EPO has been activated, the UPS must be manually restarted. (The EPO also may be
activated remotely by a contact closure.)
CAUTION
Anytime the UPS has been shut down by using the
EPO, the system should be carefully checked by trained
facilities personnel before restarting.
3.5 System Controls
Controls for the UPS, with the exception of the pushbuttons located on the face of the
UPS monitor panel, are situated inside the front door of the cabinet.
MAIN INPUT CIRCUIT BREAKER: Available with optional input isolation
transformer only. When closed, allows input power to activate the input isolation
transformer which supplies control power, rectifier, SBS and maintenance bypass inputs.
UPS CONTROL switch: This switch is rotated clockwise to energize the power
supply to turn on the Digital Signal Processor logic.
RECTIFIER INPUT CIRCUIT BREAKER: When closed, allows UPS input
power to supply the rectifier and, on units having an optional input isolation transformer, the
SBS input.
BYPASS CIRCUIT BREAKER: Used primarily for maintenance purposes. When
closed, it enables the UPS electronics to be de-energized for maintenance procedures while
continuing to supply power to the critical load.
