By pressing the ON-OFF button again the VM24 switches itself off. In addition, the
instrument has an automatic shut-off timer for saving the battery power (cf. Chapter
4.4).
4.3. Battery Display and Battery Type
In the upper left corner of the VM24 display there is a battery level indicator (10).
When the green battery symbol is full, the battery is fully charged.
While non-rechargeable batteries have a cell voltage of 1.5 V, NiMH rechargeable
batteries deliver only 1.2 V per cell. The VM24 battery indicator can be adjusted to
both voltages. To adjust the voltage, open the main menu by pressing F3 and scroll
through the menu options by repeatedly pressing the ▼ button until you reach 'In-
strument Settings', then press OK.
Within the sub-menu select “Battery type” (11) by following the same instructions
as before and then by pressing▼ select between “Alkaline” (non-rechargeable, 1.5
V) or “NiMH accu” (rechargeable, 1.2 V). Confirm your choice by pressing OK and
exit the menu by pressing F3 repeatedly.
If the power supply drops below 3.3 V when using alkaline batteries or below 3 V
with rechargeable batteries, the battery indicator becomes red. Further measure-
ments can be taken until the power supply reaches 2.8 V in keeping with the instru-
ment specifications. At this point the battery level indicator is completely empty and
the instrument switches itself off automatically.
If the VM24 is connected to a USB port, it will be supplied by the USB voltage in
order to spare the batteries. In this case, “external” is displayed on the screen instead
of the battery level indicator.
10
Figure 10: Battery indica-
tor upper left
Figure 11: Select battery type
