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c) Low Voltage Monitoring
The QuadroCopter constantly monitors the voltage of the connected battery. When the battery's charge end voltage is
reached (threshold value approx. 9.4 V), the red LED (LD2) starts to flash quickly. At the same time, the signal encoder
starts to buzz at a slow rhythm. Land at once when you notice these signals.
If you ignore these signals, the battery will be discharged further and the signal encoder will start to buzz at a quick
rhythm.
If the alar signals are still ignored, the flight control will switch off the motors when the battery drops below
a specified voltage. The QuadroCopter will crash. Loss of guarantee/warranty!
This flashing LED indicator can only be switched off by disconnecting the battery.
In order to detect a low rechargeable battery during flight, it is recommended that strong throttle thrusts be carried out
from time to time. If the QuadroCopter responds slowly and weakly, it should be landed and the rechargeable battery
should be checked. Due to the performance, this test is, however, difficult to realize.
In the case of a long, uninterrupted flight operation, it is recommended to also test the LED indictors through time to
time landing.
Practical advice:
To avoid damage to the QuadroCopter from crashing by undervoltage or damage to the rechargeable
battery from deep discharge, we recommend that you observe the low voltage light signals without fail.
As the integrated LEDs on the flight control will only flash in one direction, we recommend installing addi-
tional LEDs to display threatening undervoltage by light signal.
Place the LEDs at an appropriate position in the QuadroCopter. To activate the LEDs, observe the notes in
chapter "Information on the Combiboard QC 08". Alternatively, we recommend additional installation of
the LiPo-saver (Conrad order no. 230327). The Lipo saver warns you of impending low voltage by light
signal. Place the LiPo Saver on the appropriate place of the QuadroCopter and connect it , e.g. via the
battery's balancing connection.
d) Bootloader Operation
In bootloader operation, LD1 (green LED) must be lit continually at approx. 1 Hz. LD2 (red LED) flashes during
communication with the computer in a quick, differing rhythm.
