HP PowerTrust A3589A, Manual

Page: 41 / 257

Chapter 1 1-19
Overview
Control Panel Switches and Indicators
CAUTION Do not push the red button while the UPS is operating on battery. Damage to
the connected equipment can occur.
CAUTION
Should the AC power fail while the Service Bypass switch is set to
BYPASS
, all
of the connected equipment will lose power immediately.
The PowerTrust UPS output is not protected by the MAIN INPUT circuit
breaker when in Bypass mode; instead, it is protected by the BYPASS INPUT
breaker. The Bypass switch should always be in the
NORMAL
position, unless
instructed otherwise by a Hewlett-Packard service representative.
10
Bypass Switch
Activation Button
This red button must be pressed to change the Service Bypass
switch setting from
NORMAL
to
BYPASS
. (The button does not have to
be pressed to change the setting from
BYPASS
to
NORMAL
.) Pressing
this button will put the UPS into Automatic Bypass mode. To avoid
loosing AC power to the protected equipment, you should always
check that the BYPASS INPUT circuit breaker is ON before
pressing this button.
11
Service Bypass
Switch
This rotary switch allows you to isolate and disconnect the AC input
from the Electronics Unit and batteries so that these components
can be serviced without disrupting power to the connected
equipment. This switch is also used to manually override automatic
bypass.
The bypass switch can be set to two positions,
NORMAL
and
BYPASS
.
Normal Mode. When the switch is set to
NORMAL
, the AC power
source provides power to the Electronics Unit. Should the AC power
fail while the Service Bypass switch is set to
NORMAL
, the UPS
automatically switches to On-battery mode. When input power is
restored, the Electronics Unit returns to On-line mode.
Bypass Mode. When the switch is set to
BYPASS
, the AC power
source bypasses the Electronics Unit but continues to supply power
to the load.
The
BYPASS
setting is used to service the Electronics Unit or Battery
Box. The UPS cannot switch to battery power if AC input power is
lost when the Service Bypass switch is set to
BYPASS
.