Betaflight battery settings

The voltage meter source has three values. None turns the meter off. Onboard ADC reads the resistor divider on the flight controller. ESC sensor reads voltage that the ESC reports, which only works when the ESC protocol and the port are already sending that telemetry. FlySpark labels those three the same way Betaflight does.

Onboard ADC is the usual choice on a board that has a VBAT pad and a divider. The scale for that meter is on the voltage meters card, not in the source dropdown. If the live voltage is a long way from a handheld meter on the balance lead, change the scale, not the warning voltage. The warning can only be honest after the scale is honest.

ESC sensor is the right source when the ESCs report voltage and the flight controller is set to listen. That path needs DShot telemetry or the ESC sensor feature the board actually supports, and it needs the motor protocol and the port left in a state that carries the telemetry. If you select ESC sensor and the voltage sits at zero, the sensor is not arriving. Go back to onboard ADC if the board has a divider, or fix the ESC telemetry before you trust the pack gauge.

None is for a bench board with no pack wired to the controller. Leave it on none and the OSD battery element stays empty. Do not leave it on none for a craft that flies.

Minimum, warning and maximum are per cell, not for the whole pack. Each one is stored in hundredths of a volt and shown with two decimals, from 1.00 to 5.00 volts. The warning is the value that should get your attention in the air. The minimum is the lower limit the firmware treats as empty. The maximum is the full-cell value used when the gauge draws a full pack.

A 4S pack does not get a special field. Betaflight multiplies the cell value by the cell count it detects. If the cell count is wrong, every warning is wrong by that ratio. A craft that thinks a 4S pack is 3S will hit the warning voltage while the cells are still fine, or the other way around if the count is high. Confirm the cell count the OSD shows against the pack you plugged in before you change the warning.

Set the warning for the chemistry you fly. A LiPo that you want to land at about 3.5 V per cell needs the warning near that number, with the minimum a little lower so you still have a moment after the warning starts. A Li-ion pack uses a different curve. The tab will accept 1 to 5 volts either way. It will not pick the chemistry for you.

The live card on the Power tab shows the voltage the board is reporting now. Compare it with a meter on the balance plug, at rest, before you arm. A difference of a tenth of a volt per cell is enough to fix the scale. Do not chase hundredths while the pack is under load. Sag is real, and the warning exists so you land when the loaded voltage falls, not so the resting number matches a charger to the last digit.

The current meter source has five values. None, onboard ADC, virtual, ESC sensor and MSP. Onboard ADC is a current sensor wired to the flight controller, often a shunt on the board or a separate sensor. Virtual estimates current from throttle, which is a rough guide and a poor mAh counter. ESC sensor uses current the ESCs report. MSP takes current from a device that speaks MSP. Pick the one the hardware actually provides.

Capacity is the pack size in milliamp hours, from 0 to 20000, in steps of 50. It does not measure the pack. It tells the mAh counter how big this pack is so the used-capacity warning has a target. A 1500 mAh pack typed in as 1300 will warn early. A 1500 typed in as 1800 will warn late. Change it when you change packs, or use a battery profile if you swap sizes often.

Virtual current will still draw a number, and that number is not a calibration. If you care about mAh, use a real sensor and check it. Fly a known pack, write down the mAh the OSD claims, and compare it with what the charger puts back in. If the OSD is consistently high or low, change the current scale on the current meters card. If it is randomly wrong, the source is the wrong one or the sensor is noisy.

ESC current and onboard current are not interchangeable scales. A scale that was right for a shunt on the board is wrong for ESC telemetry, and the reverse is also wrong. When you change the source, expect to redo the scale. Leave the cell warning voltages alone while you do that, so you only change one thing.

Each meter has a scale. The voltage meters card and the current meters card are separate from the source dropdown. The scale is the number that turns the raw sensor into volts or amps. FlySpark shows those cards on the Power tab, and it has a calibration card so you can line the reported value up with a meter you trust.

Calibrate voltage at rest. Plug in the pack, read a handheld meter on the balance lead, and adjust until the Power tab matches. Do this before you change the warning. If you lower the warning because the OSD looks low, and the real problem was the scale, you have taught the craft to fly a low pack.

Calibrate current with a load you can measure, or with a charge cycle you can compare. A small error matters more on a small pack. A 10 percent high current scale on a 1500 mAh pack reports 150 mAh you did not use, and you land early. A 10 percent low scale does the opposite. Write the scale down with the board backup from the CLI so a later diff still contains it.

Presets sometimes ship a battery scale for a known stack. Applying a preset can overwrite the scale you just calibrated. Read the diff after a preset. If the scale changed and your meter no longer matches, put your scale back. The presets page is the place that explains what a preset overwrites.

The battery OSD elements read this tab. If the voltage element is blank, the source is none or the sensor is not arriving. If the element shows a number that does not match a meter, the scale is wrong. If it matches at rest and sags in the air, that is the pack under load, and the warning voltage is how you decide when to land.

Used capacity only moves when a current source is producing amps. Virtual current moves with throttle even on the bench. A real sensor should sit near zero with the motors stopped. A sensor that shows several amps at idle needs its offset or its scale fixed before you trust the mAh count. The current meters card is where that offset lives.

Arming does not require a battery meter. You can arm with the source on none. That is a bad setup for anything you fly away from the bench, because nothing will tell you the pack is done. Set the source, confirm a live voltage, then fly.

The OSD editor only places the elements. It does not set the volts. If you move the voltage element and the number is still wrong, come back to the Power tab. Layout and scale are different jobs.

INAV measures voltage with its own meter type and a voltage scale, and it stores cell count, cell detection voltage, and minimum, warning and maximum cell voltages on its power pages. Current uses a scale in millivolts per 10 amps and an offset in millivolts. Those fields are not the Betaflight cards. A Betaflight scale pasted into INAV will not mean the same volts.

Open the INAV configurator for an INAV board. The live voltage is still the test: meter on the balance lead, then the scale, then the warning. The order is the same even though the field names differ.

The Betaflight demo in FlySpark is a simulated 4.5 board. You can open the Power tab and see the sources and the cell fields without hardware. Writing them to a flight controller needs a connection. Chrome and Edge use USB or Bluetooth. The Android app adds Wi-Fi. iPhone uses Bluetooth or Wi-Fi and cannot see a flight controller over USB.