APC BK250EI Power Supply User Manual


 
Page 18
5.0 Controls and indicators
5.1 Power I/0 switch
The power I/0 switch controls power to the UPS and its output
receptacles. When the switch is on, the UPS operates and your
computer equipment will be powered. When the switch is off, the
UPS is de-energized and your equipment is unpowered. If your
equipment switches are left on, the entire system can be operated
by using just the power I/0 switch! The lamp within the power I/0
switch illuminates whenever normal voltages are present at the
output receptacles. When the switch is in the on position and the
lamp is extinguished, the UPS has shut down due to overload or low battery.
5.2 Test/Alarm Disable switch (on units so equipped)
When operating during a utility power outage, the UPS will emit a beep once every five
seconds. This beep can be silenced by pressing the Alarm Disable control (bottom of
toggle switch.) However, the UPS's low battery warning will still
sound in the event of an extended utility outage.
When the Test portion of the Test/Alarm Disable switch is pressed,
(top of toggle switch) the UPS simulates a power outage and
transfers your load to the alternate power source. This feature
allows you to determine that computer equipment protected by
the UPS operates normally during transfers. It also provides a
convenient means of testing the UPS’s battery. If the Test control is held depressed, the
UPS will operate your equipment from power derived from the battery continuously. If
during the test the low battery warning is sounded prematurely and the load is known to
be normal, then the battery is weak and requires extended recharge or replacement (see
section 7.0).
5.3 Audible alarm
During a utility failure, the UPS emits a beep once every five seconds to warn you that your
equipment is operating from a source of power which is limited in duration. The alarm
can be defeated using the Alarm Disable switch (on units so equipped) or, in advance of
the outage, via option switch #1. In the event of an extended utility failure, the UPS will