User’s Manual
7
6
Principle of Operation
6.1
Power Consumption
The
ABC-Mems
is always on. However, when not in operation it only measures time, which only takes
a tiny operating current. In that
Idle
state it can stay on for up to 6 months
.
When the
meter
is
actively measuring, its power consumption is mostly affected by two factors:
•
The accelerometer sampling rate.
•
Whether it is recording raw signals or statistics.
The
meter
can be configured to connect to a server at regular intervals. When that function is
enabled, the
meter
will activate its
WiFi™
interface at the defined interval, and attempt to connect
via
WiFi™
for up to 1 minute. During that time, the instrument’s power consumption will be increased. If
the connection fails the
meter
will fall back to its previous state (Sleep or Recording).
Note:
WiFi™
communications consume battery, so when leaving the
meter
unused for a long
time, it is important to disable the
WiFi™
periodic connection feature.
In order to minimize the power consumption due to
WiFi™
reporting, choose a longer
WiFi™
connection interval, for instance 1 hour. Make sure that the router is well within range of the instrument.
WiFi™
consumption is greatly increased when the
WiFi™
signal is weak.
The
Instrument_Manager
application automatically calculates and displays the cumulative number of
days that the battery would last while recording, as a function of the instrument settings.
Note:
That indication does not take into account any
WiFi™
reporting.
In applications where the
meter
must record for longer periods of time, it can be connected to a
USB charger. For outdoor-use, a USB-output solar panel,
that will power the instrument indefinitely.
6.2
Battery Charging
The battery charges whenever the following conditions are met:
•
The battery is not already fully charged.
•
The instrument is connected to a PC’s USB port and the PC is not in standby, or
•
The instrument is connected to a USB charger.
Note:
In order to charge the instrument properly, use a USB charger that is either compliant with the
USB charging specification (most commercial dedicated USB chargers), or the Apple charging
specification (most Apple chargers that have a USB output). We do not recommend using the USB
outputs of cell-phone chargers, as many do not follow either standard.
While charging, the charge LED is orange. When fully charged, the LED changes to green.
The charge time from a completely discharged state varies with the amount of power the PC allows the
instrument to draw. Charge time is normally around 2H30. If the PC does not allow the fast charge
current, the charge time can increase up to 5 to 6 hours.