Welch Allyn AM 232 Manual Audiometer - User Manual - Manual (Page 20)

20 12-16-08
NiCad BATTERY OPERATION
The AM 232 Manual Audiometer battery option is supplied with an installed,
rechargeable NiCad battery pack. It requires about 18 hours to charge fully, which will
provide about 22 hours of continuous operation. The green LED on the pack itself
illuminates when charging is in progress. The words LO BAT illuminates on the front
panel LCD when the battery charge is getting low, alerting you to recharge the
batteries. When LO BAT appears, the instrument will operate (continuously) for
about two more hours before it shuts down completely.
Note: In no instance will loss of battery power affect the instrument calibration.
To save battery life, the AM 232 Manual Audiometer has a special “Sleep Mode” in
which the instrument will shut down after 5 minutes of no operation. You will know
the instrument is “asleep” because the LCD will show three dash lines (- - -). To
“wake up” the instrument, press the Present bar. There is no danger of presenting a
loud tone to the test subject when the instrument “wakes up” because no tone is
presented until the Audiometer is awake. In addition, the instrument automatically
resets its output to 0 dB HL.
If the AM 232 Manual Audiometer is operated until the battery charge has dropped
below an acceptable voltage level, the instrument will cease to function. The display
will be blank except for the LO BAT indication, and the controls will cease to
function. To restore operation, the batteries must be recharged for some period of
time, up to 18 hours (full charge), or line power (mains) may be used. If the Audiom-
eter is operated off of line power (mains) with the rechargeable batteries in place,
some battery charging will occur.