HP Tc4400 Power - Page 24

7 Battery packs When a charged battery pack is in the computer and the computer is not plugged into external power, the computer runs on battery power. When the computer is plugged into external AC power, the computer runs on AC power. If the computer contains a charged battery pack and is running on external AC power supplied through the AC adapter, the computer switches to battery power if the AC adapter is disconnected from the computer. ✎ The display brightness is automatically decreased to save battery life when you disconnect from AC power. To increase display brightness, press fn+ f10 or reconnect the AC adapter. You can keep a battery pack in the computer or in storage, depending on how you work. Keeping a battery pack in the computer whenever the computer is plugged into external AC power enables the battery pack to charge and also protects your work in case of a power outage. However, a battery pack in the computer slowly discharges when the computer is turned off and not plugged into external power. Power 7-1