Change The Battery Pack; Reactivate The Battery - HP iPAQ h5400 Series Reference Manual

2. Tap System, and then the Power icon.
3. Tap the Standby tab.
4. Drag the pointer to adjust the standby period.

Change the Battery Pack

If the main battery for your iPAQ Pocket PC is removed, your
device will not operate even if you try to use AC power.
You can change the battery without losing data. However, any
device activity and/or wireless communication will be
terminated.
It is recommended that you replace the removable battery within
30 minutes to avoid losing data.

Reactivate the Battery

A full reset will deactivate the battery. The power button will not
function until the battery is reactivated.
You reactivate the battery by:
Removing and reinstalling the battery
Connecting the iPAQ Pocket PC to AC power
Reference Guide
Getting Acquainted
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