S 4.31 Ensuring power supply during mobile use

Initiation responsibility: User

Implementation responsibility: User

In order to be able to maintain the power supply of a portable PC or PDA even during mobile use, rechargeable batteries or batteries are normally used. Depending on the capacity of the rechargeable battery and/or battery and the design of the portable terminal device, this covers a limited period of time, e.g. a few hours. In order to prevent data in volatile memories from being lost upon a loss of operating voltage, some general conditions should be met:

• The warning signals of the portable terminal device (if present) indicating the voltage drop must not be ignored. The warning signals should be configured in such a way that there is sufficient time to backup the data after the first warning.
• If it is foreseeable that the mobile use will be for a longer period, rechargeable batteries must be charged in advance and charged spare batteries must be brought along, if applicable.
• Especially with older rechargeable batteries, the times of use are shorter and they may be discharged very quickly when reaching their capacity limits. Therefore, regular data backups must be performed during operation in order to avoid a loss of data. Since such rechargeable batteries may also discharge quickly in standby mode, the state of charge should be checked regularly and backups of the configuration data of the laptop or PDA must be brought along for cases of emergency. It is recommendable to replace the rechargeable battery with a new one as soon as such signs of ageing occur.
• For charging, the information in the manual of the mobile IT system should be taken into consideration so that the service life of the rechargeable battery is not affected adversely.

• Before starting a journey and/or when handing over a mobile IT system, the sufficient state of charge of the rechargeable batteries or batteries must be ensured. The state of charge of the rechargeable batteries should be checked regularly, since a rechargeable battery discharges over the course of time if it is not used.
• The charging adapter should be brought along optionally.

Furthermore, it is recommendable to store the processed data to a non-volatile medium at short intervals during the use of the mobile IT system. Automatic data backups in standard programs may be used to this end.

If a longer period of use of the mobile IT system is foreseeable, e.g. during business trips, a charged spare rechargeable battery should be brought along. The spare rechargeable battery should be stored in a protective cover, since damage may be caused by overheating or fire if the contacts of the rechargeable battery come into contact with conductive materials. This can be caused by many ordinary objects such as keys or chains.

Any kind of IT system should be switched off before the rechargeable battery is replaced so that the memory is not damaged

Note:

The worst storage location for rechargeable batteries (especially lithium ion batteries) is the switched on laptop in stationary use, i.e. while the laptop is connected to the power grid via the socket. If operated in a docking station, the rechargeable battery should be removed in advance, if possible.

Review questions:

• Have the users received information as to how they can ideally guarantee the power supply during mobile use?
• Is the processed data backed up to a non-volatile medium at short intervals?
• Are spare rechargeable batteries stored and transported in corresponding covers?