I’m having an issue with my varying voltage on a drone. Drone hardware:
PL Sensor (14s)
Herelink Blue & Airunit
Here3 gps x2
Max Amps 10s2p Li-Ion battery
My issues: I’m getting inconsistent voltage/% of batt/mah. readings from the Herelink (QGC). I have tried and failed to get a consistent reading. I have read and followed several “how to” guides to remedy this issue with no luck. The last two Mauch PC4/V3’s I’ve ordered did not come with the voltage divider, or the A/V numbers. Just (-- --) in those boxes. When setting up the voltage and current settings in QGC or Adrupilot, these are needed to get accurate reading on volt., amp., mah, % of batt, ect. So instinctively I looked to Mauch for answers. There website is currently down with no way to contact them. So I am reaching out the masses to see if there is another way to acquire these values? Absolutely any information is appreciated. Thanks in advance.
Use 10.0 for volts divider and 64 for amps/volt as a starting point
You can use the voltage calibration in MissionPlanner or QGC to accurately set the volts divider by measuring the actual battery voltage with a digital multimeter, and type in the measured value where appropriate.
Here’s how to adjust your Amps Per Volt
- Plug in a fresh battery and do a hover flight for 5 minutes or until you’ve used a significant amount of battery capacity
- Immediately unplug the battery and charge it, note how many mah’s it took to charge. Let’s say that was 1,500 mah
- Download your log and look at maximum CurrTot. Let’s say it was 1,300 mah
- Get your existing BATT_AMP_PERVOLT setting from Mission Planner, let’s say 17
NEW_AMPS_PER_VOLT = OLD_AMPS_PER_VOLT x CHARGED_MAH / LOGGED_MAH
With my example numbers, you’d get
NEW_AMPS_PER_VOLT = 17 x 1,500 / 1,300 = 19.61
- Set the new value in the BATT_AMP_PERVOLT parameter and save to your copter
- Fly to check, repeat until you’re happy the new value gives consistent readings
Thank you so much. After numerous conversations with Christian Mauch, I have determined that there in no needed A/V or V divider numbers because I have the PL Sensor installed. And the absolute way to preform this offset and values is using your math to get my values. I’m now within 25mah of used/telem used. I really appreciate this help. Its detailed information like this that makes this community great. Now its time to upload some logs to get help PID tunning this big girl. Thanks again.