1.3 Charging the Instrument
The AML-3 LGR instrument uses an internal battery for operation. The battery typically requires
a charging top-up when the instrument is first received by the user.
The battery must be charged when the LED indicator flashes red, failure to maintain charge in
the battery can cause damage to the instrument.
The instrument is charged via its USB-C connector, either through connection with a compatible
USB port or via the provided wall wart (recommended). Note that it is common for USB ports to
have insufficient power to simultaneously charge and operate the instrument, so it is
recommended that the wall wart be used to charge the instrument.
The instrument body may
get warm during charging.
This is normal and a result of the instrument’s fast-charge
capability.
Applying power through the USB-C connector does not automatically turn the instrument on,
and the instrument may be charged with the switch in either the ‘on’ or ‘off’ position. Charging is
fastest with the switch set to ‘off’ - typically on the order of 8hrs.
When deploying an AML-3 LGR Instrument where the indicator cannot be viewed directly, it is
recommended the internal battery thresholds be modified to protect the internal battery from
completely discharging, causing damage to the instrument. The command for this can be found
in Section 5 under the power commands. AML recommends increasing the battery shutdown
voltage to 6.9V in this deployment case.
1.4 Auxiliary Sensors
It is possible for AML-3 instruments to be equipped with sensors which are not installed on the
instrument sensor endcap, such as Dissolved Oxygen (DO) and PAR sensors. These are
referred to as auxiliary sensors and may be either fastened to the side of the instrument body or
installed on adjacent moored equipment. In all cases, auxiliary sensors are connected to the
instrument via a waterproof connector on the Connector Endcap, providing power and
communication (note that Figure 1 does not show any auxiliary sensors).
It is typical for auxiliary sensors mounted on the side of the instrument to be protected by a
stainless steel guard.
1.5 GPS Functionality (500m Only)
AML-3 LGR instruments come equipped with on-board GPS + GLONASS functionality. The
instrument will automatically power its GPS module and begin signal acquisition immediately
upon bootup. In general, lock times are expected to occur in 5 minutes or less after bootup,
though they may take longer in challenging conditions. For best GPS performance, ensure the
instrument is located outdoors and with a direct line of sight to the horizon and sky above. It is
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