Covidien Nellcor OxiMax N-600x Operator's Manual page 37

Operating the Battery
available on the existing battery charge. Refer to Table 4 for a
description of the low and critical battery conditions.
A low battery audible alarm can be cancelled by pressing the
ALARM SILENCE button. The low battery indicator and display
screen message continues to display. Connecting the monitor to
an AC power source silences the audible alarm, but the low
battery indicator remains lit as long as the battery is in the low
voltage condition. After the 15-minute period of low battery
condition, a high priority alarm sounds for about 10 seconds
before the monitor shuts off.
If the monitor backlight is turned off during a low battery
condition, the backlight cannot be turned back on.
Nellcor recommends that a qualified service personnel replace the
internal battery every 24 months. Replaced batteries should be
disposed of in accordance with local ordinances.
Caution: The pulse oximeter default settings will return to
factory default setting if the battery becomes fully
discharged or is replaced. Qualified service personnel will
have to reset the institutional defaults, following the
instructions in the N-600x Service Manual.
Note: If the AC voltage selector switch on the monitor rear panel
does not match your AC voltage source, the monitor may run on
battery power, even though it is connected to an AC power
source, which eventually results in a low priority alarm and a
lighted low battery indicator. Ensure that the switch setting
matches your AC voltage.
Note: As the battery is used and recharged over time, the
amount of time between the onset of the low battery alarm and
the instrument shut-off may become shorter.
N-600x Operator's Manual 29