Do any FC AIO/ESC manufacturers give you the correct parameters to plug into BetaFlight for accurate ADC voltage and current measurement?

Brand new BetaFlight AIO flight controller had 100 for current scale and -500 for offset.  After some flights I see this is 4X higher than it should be.

Betaflight defaults for current scale and offset are 400 and 0, respectively.

Doing some test flights, recording mAh from OSD, re-charging (fast, not balancing), recording mAh put back in, and trying BF default values and calculated values to get closer to reality.

Is it really that hard for manufacturers to do a little calibration and provide some ballpark numbers ?

Matek usually were good about listing the current sensor scale. Otherwise, most other manufacturers let you fend for yourself.

Usually it's best to just check to see if they offered up values to use before buying. If they don't give you any, a multimeter is your buddy. Voltage is pretty simple, as you just adjust the number until each reads the same. With current, I use a current clamp to get close, then see if the used mAh comes up accurately at the charger.

If I remember correctly for current you have to use y=mx+b, where

• Y is the current reported by BF
  
• M is the scale/slope
  
• X is the amount of throttle
  
• B is the offset/y-intercept
  

You need a linear throttle curve, a multimeter or ammeter, one hand to hold the drone securely, the other hand to operate the throttle.  Props have to be on because actual current readings under actual load need to be measured.  I did this with a whoop once, and it worked great, but would never try it with a 5” or similar size.

You hook everything up and with throttle at 0 you read the current on the multimeter/ammeter and adjust offset in BF until BF reports the same.

Then you have to take various readings at different throttle levels to find the scale/slope where BF reads the same.  This is the dangerous part obviously, and the reason almost everyone's current readings are wrong.

If you don’t find correct values for both scale and offset then readings will be off across the range of throttle, and then what's the point ?

I suppose you could do something similar by loading down the onboard regulators instead but then it would be helpful for them to disclose their max current ratings.  And the samples won’t be as spread out across the ESCs range like could be achieved by running the motors with props on.  The samples would  all be close to the idle/zero throttle current value so the resulting scale wouldn’t be as accurate.

Or, we can avoid all this potential danger and have the scale and offset values specified by the manufacturer.  For us to do this safely we need to make the appropriate cables & connectors if using a multimeter (you don't want to be attempting to hold probe wires cuz you'd need a 3rd hand) and a secure mechanism (not your 2nd hand) for holding the drone from moving and chopping measurement wires, and yourself.

Yes voltage is easy and much safer to measure.

For current sensor calibration I've used Pawel's method detailed in the post linked to below. I do admit that doing it that way is quite scary with a 5" quad but the props being upside down suck the quad to the workbench so it's not going anywhere. You don't even need to hold the quad down if you don't want to because it does that itself by running inverse props. You just need to be very careful not to move the pitch, roll, or yaw stick axis

https://intofpv.com/t-how-to-calibrate-y...ent-sensor