abem Terrameter LS, Instruction Manual

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ABEM Terrameter LS
7
2.5 The Power Supply
During stand-by the instrument drains very low levels of current. During transmission
though, the Terrameter LS will, depending on the circumstances use large currents,
sometimes up to 30A. The external battery and its cable must be designed
accordingly. Use the supplied cable set if possible. For field operations a good,
adequate in capacity and recently charged battery is vital for the best performance.
The internal battery is primarily designed as a backup power source for operating the
instrument during set up, data transfer etc. but it may also be used for limited low
power surveys. It has a quite snug fit in the battery compartment and there is no
reason to remove it when charging. If the protective liner that keeps the cells together
is found defective during inspection, please contact ABEM support for further
information.
It is possible to fully run the Terrameter LS without the internal battery but for your
convenience you should always charge the battery before starting measurement
activities.
Once the instrument has been turned on and the external battery for any reason is
disconnected it will automatically switch to the internal battery. This function even
works during the initial start up process. This useful feature makes it possible to
disconnect the external battery temporarily without shutting the instrument off when
for instance moving from one measurement station to another.
The battery-switching device will, in any situation, give priority to the external battery
if its voltage is more than 9 V. There is no direct means to read out which one of the
batteries that is in use in a specific moment. However, provided that the internal
battery is charged, the battery indicator gives an indication. After hours of work the
external battery is going to be low in voltage. If, in that situation, the battery indicator
shows a fully charged battery the reason for that is that the internal battery now is
giving power to the instrument. More information about the internal and external
voltage levels can be found in chapter 4.6 The Power Source.
Table 1 below shows a guideline to the battery indicator. The values are not very
exact but give an indication of the voltage level of the battery pack in use for the
moment, that is, the external or the internal battery. The battery indicator is the
leftmost of the
Notification Icons on the Status Bar (Figure 7).
Indication Approximate voltage
Over 12.2 V
11.6 – 12.2 V
11.4 – 11.6 V
10.9 – 11.4 V
Under 10.9
Table 1 Battery indicator