990-5022A, Revision 2 6/99
PowerStack 450 Quick Reference Guide English

About Your New PowerStack UPS

This Uninterruptible Power Supply (UPS) is designed to prevent
blackouts, brownouts, sags and surges from reaching your computer
and other valuable electronic equipment. This UPS also filters out
small utility line fluctuations and isolates your equipment from large
disturbances by internally disconnecting from the utility line, while
supplying power from its internal batteries until the utility line
returns to safe levels.
While running on battery, an internal alarm will sound (periodic
beeps).
If the utility power does not return, the UPS will continue supplying
power to the connected equipment until exhausted. A continuous
beeping will sound two minutes before the UPS’s final low battery
shutdown. If using a computer, you must manually save your files
and power down before the UPS turns itself off.

Installation and Setup

1. Install UPS
• Plug the power cord into the power supply.
2. Connect Equipment
• Do not power laser printers through the UPS.
• Use your equipment’s power cords to connect to
the UPS.
• Turn on all connected equipment.

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3. Turn on UPS
• Press the UPS’s ON switch to turn on your UPS.
This will power-up connected equipment.
• The unit performs a self-test automatically when
turned on, and every two weeks thereafter.
• The UPS charges its battery whenever it is
connected to utility power. The battery charges
fully during the first 4 hours of normal operation.
Do not expect full runtime during this initial charge
period.

Troubleshooting

Use the chart below to solve minor UPS installation problems.
Contact APC for assistance with complex UPS problems. See the
User’s Manual for a location near you.
Problem and
Possible Cause
Solution
UPS will not turn on.
• ON button not pushed. Press the ON button once to power the
UPS and the load.
• UPS not connected to AC
power supply. Check that the power cable from the
UPS to the power supply is securely
connected to the AC power source.
• UPS input circuit breaker
tripped. Reduce the load on the UPS by
unplugging equipment and reset the
circuit breaker (on back of UPS) by
pressing the plunger back in.
• Very low or no utility
voltage. Check the AC power supply to the UPS
with a table lamp. If very dim, have
the utility voltage checked.
• Battery not connected
properly. Confirm the battery connections.
UPS will not turn off.
• Internal UPS fault. Do not attempt to use the UPS. Unplug
the UPS and have it serviced
immediately.
UPS operates on-battery although normal line voltage exists.
• UPS’s input circuit breaker
tripped. Reduce the load on the UPS by
unplugging equipment and reset the
circuit breaker(on back of UPS) by
pressing the plunger back in.
• Very high, low, or distorted
line voltage.. Move the UPS to a different outlet on a
different circuit.
UPS beeps occasionally.
• Normal UPS on battery
operation. None. The UPS is protecting the load.
UPS does not provide expected backup time.
• The UPS’s battery is weak
due to recent outage or is
near the end of its service
life.
Charge the battery. Batteries require
recharging after extended outages.
Also, they wear faster when put into
service often or when operated at
elevated temperatures. If the battery is
near the end of its service life, consider
replacing the battery even if the replace
battery indicator is not yet lit.
• The UPS is overloaded. Check the UPS’s load display. Unplug
less needed equipment, such as printers.
All indicators are lit and UPS emits a constant beeping.
• Internal UPS fault. Do not attempt to use the UPS. Turn
the UPS off and have it serviced
immediately.
Overload indicator is on and beeps constantly.
• UPS is overloaded. Unplug less needed equipment, such as
printers.
The replace battery light is lit.
• Weak batteries. Do another self test to see if it clears.
• Replacement batteries not
connected properly. Confirm the battery connections.