Power Failure Operation - HP PowerTrust A3589A Manual

Power Failure Operation

When utility power fails, the UPS supplies internally generated AC voltage from its
batteries for approximately fifteen (15) minutes at full load. As soon as the UPS detects
a utility power failure, it generates an audible alarm. The alarm will sound
approximately once every 10 seconds. When the UPS's battery charge level is within
approximately three (3) minutes of full battery discharge, the UPS initiates a different
audible warning: a repeating pattern of three beeps followed by approximately ten
seconds of silence. When this happens, you should immediately prepare for loss of battery
power by powering down your protected equipment. After any power failure, the battery
hold-up time is reduced until the batteries are again fully charged.
The UPS automatically switches to battery operation when the following abnormal
conditions exist:
• A complete AC power failure.
• AC power falls below a predefined voltage.
• AC power rises above a predefined voltage.
The following actions should be taken after the UPS detects an AC power failure and
sounds an alarm:
1. Shut down the operating system.
2. Power down the protected equipment.
3. Switch the UPS Output On/Output Off switch to
4. If the power will be off for an extended time, perform the following steps; otherwise,
proceed to step 5.
a. Power off the UPS by following the steps outlined in "Powering-Off the UPS for an
Extended Time" in Chapter 4.
b. When AC power returns, follow the steps outlined in "Initial Power-On or Power-On
After Shutdown" in Chapter 4.
5. Once the AC power returns, switch the UPS Output On/Output Off switch to
6. Power up the protected equipment.
7. Restart the operating system.
When the AC power is restored, the UPS will automatically recharge its batteries as long
as the UPS/BATTERY switch is set to
the ON position.
Recharging the batteries can take up to 14.5 hours at 25° C ambient operating
temperature for a 90% recharge. The recharge time may be considerably less if the
batteries are not fully discharged.
Chapter 1
Output Off
and the MAIN INPUT circuit breaker is in
ENABLE
Power Failure Operation
. Refer to Figure 1-3.
Output On
Overview
.
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