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2 battery calibration, Battery calibration – Psion Teklogix Netbook Pro none User Manual

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Psion Teklogix NETBOOK PRO User Manual

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Chapter 2: Getting Started

Power Properties

This tab describes the main and backup batteries, and their state. A warning message
to change or recharge the battery appears when the main or backup battery levels
become critically low.

Note: The main battery can run until the computer shuts off: at this point there

will still be enough power in the battery pack to preserve the system state

without relying on the backup batteries. If allowed to discharge further,

eventually the backup batteries will automatically take over

This tab includes a checkbox, Using multiple main battery packs. When this check-
box is selected, the NETBOOK PRO calibrates each battery pack anew each time
the pack is inserted. When this checkbox is not checked, the NETBOOK PRO
retains the battery calibration information when the battery pack is removed. See
“Battery Calibration” below for details.

This tab also displays an indication of charge or discharge current for the main bat-
tery. The user can see how the current varies as the main battery charges and dis-
charges, the backlight is adjusted, or a peripheral card is inserted. (Again, see
“Battery Calibration” below for details.)

Note: The current measurement displayed may be up to ten seconds old.

2.5.2.2

Battery Calibration

The NETBOOK PRO uses ‘battery calibration’ to increase the accuracy of the
remaining charge indication for its rechargeable battery.

When a battery pack is first connected, the NETBOOK PRO tracks its discharge and
charge current and voltage over a full discharge/charge cycle. This enables it to form
a picture of how the battery behaves, and thus give accurate estimates of how long
the charge will last during day-to-day use. An indicator beside the estimate of
remaining charge in the main battery displays either ‘Not calibrated’, ‘Calibrating’,
or nothing:

When the Battery tab of the Power Properties dialogue displays the ‘Not
calibrated’ message, the NETBOOK PRO has not yet calibrated the battery.

When it displays the ‘Calibrating’ message, the NETBOOK PRO is setting
up its battery calibration. To do this, it tracks the performance of the battery
through a complete discharge and charge cycle.