2.9 KiB
Battery Monitoring
Cleanflight has battery monitoring capability. Battery voltage of the main battery can be measured by the system and used to trigger a low-battery warning buzzer, on-board status LED flashing and LED strip patterns.
Low battery warnings can:
- help to ensure that you have time to safely land the aircraft.
- help maintain the life and safety of your LiPo/LiFe batteries which should not be discharged below manufactures recommendations.
Minimum and maximum cell voltages can be set, these voltages are used to detect the amount of cells you are using.
Per-cell monitoring is not supported.
Supported targets
All targets support battery voltage monitoring unless status.
Connections
When dealing with batteries ALWAYS CHECK POLARITY!
Measure expected voltages first and then connect to flight controller, connecting to the flight controller with incorrect voltage or reversed polarity will likely fry your flight controller.
Naze32
The Naze32 has an on-board battery divider circuit, connect your main battery to the VBAT connector.
CC3D
The CC3D has no battery divider, create one that gives you a 3.3v MAXIMUM output when your battery is fully charged and connect the output from it to S5_IN/PA0/RC5.
S5_IN/PA0/RC5 is Pin 7 on the 8 pin connector, second to last pin, opposite end from the GND/+5/PPM signal input.
Note: When battery monitoring is enabled on the CC3D RC5 can no-longer be used for PWM input.
Configuration
Enable the VBAT feature.
Configure min/max cell voltages using the following CLI setting:
vbat_scale - adjust this to match battery voltage to reported value.
vbat_max_cell_voltage - maximum voltage per cell, used for auto-detecting battery voltage in 0.1V units, i.e. 43 = 4.3V
vbat_min_cell_voltage - minimum voltage per cell, this triggers battery out alarms, in 0.1V units, i.e. 33 = 3.3V
e.g.
set vbat_scale = 110
set vbat_max_cell_voltage = 43
set vbat_min_cell_voltage = 33
Current Monitoring
Current monitoring (Amperage) is supported by connecting a current meter to the appropriate current meter ADC input (See Board documentation).
When enabled Amps, mAh used and capacity remaining calculated and used by the telemetry and OLED display subsystems.
Configuration
Enable current monitoring using the cli command
feature CURRENT_METER
Configure capacity using the battery_capacity setting, it takes a value in mAh.
The current meter may need to be configured so that the value read at the ADC input matches actual current draw. Just like you need a voltmeter to correctly calibrate your voltage reading you also need an ammeter to calibrate your current sensor.
Use the following settings to adjust calibrtion.
current_meter_scale
current_meter_offset
If you're using an OSD that expects the multiwii current meter output value then set multiwii_current_meter_output to 1.