Maintenance
Table 5–1 Troubleshooting Status Lights
Lit Status Light
Indication
Corrective Action
Normal (green)
Normal operation. The UPS is drawing power from
the ac input line and the ac input power meets input
specifications. The UPS is in Normal mode when
the ac line voltage is 208 Vac (+10%/-15%) and the
output voltage is 208 Vac (±2%) and locked to the
line frequency.
None
Bypass (yellow)
The UPS is in Bypass mode. There is a problem in
the conditioning or battery charging electronics in
the UPS, or the battery circuit breaker on the front
panel has tripped OFF. The ac input is bypassing
the conditioning and battery charging electronics,
but is still available at the output receptacles as
unconditioned and unregulated ac.
Reset the battery circuit
breaker on the front panel.
If the UPS does not return
to Normal mode, call Digital
Services.
On Battery (yellow)
The UPS is drawing power from the battery unit.
The ac input voltage has dropped below 177 Vac.
The "On Battery" status also activates the audio
alarm.
The battery backup is limited (backup time is
typically 10 minutes under full-load). If the UPS
does not return to normal operation before the
batteries reach a predetermined low-battery cutoff,
the UPS will shut down and the load will be dropped.
Perform an orderly shutdown
of the load(s) before the
batteries reach the low-
battery cutoff.
Fault (red)
An overload, overtemperature, or internal failure
has occurred. The "Fault" status activates the audio
alarm. If the condition is harmful and persistent,
the battery circuit breaker on the front panel will
trip. When the battery circuit breaker on the front
panel trips, the UPS will automatically transfer to
Bypass mode.
If ac input power is available, the load will receive
unconditioned and unregulated ac power. If ac input
power is not available, the load will be dropped.
Call Digital Services.
Low Battery (red)
The battery voltage has dropped to a level where
only 2 to 3 minutes of backup time remains at
full-load during a prolonged ac line failure. The
"Low Battery" status also causes the audio alarm to
change tone.
Perform an orderly shutdown
of the load(s) before the
batteries reach the low-
battery cutoff and drop the
load.
Maintenance 5–3
