How to calibrate the drone current sensor? Clamp meter and charger methods

[@salukikev]

Following this I'm getting in the ball park but I don't have a starter value for "Scale" to enter. I took some guesses but I'm presently around 95 for scale. What about "Offset"? The accuracy seems to drift quite a bit the more amps I draw. Can you get an accurate result by adjusting "Scale" value only?

[@miroslavjankovic4012]

My uni-t came today and calibration proce begin...hahah...orderd that clamp meter only because your video,awesomw yob and thank you for this video!!!!

[@Terry_Fritz]

Duh!!! I never thought of reversing the prop positions. My method was to strap the quad to a piece of wood in my bench vice and hoped for the best. I survived. :D I also used the radio to spin the motors up and got weird, unstable results until I changed the flight mode from my default "Level" to "Acro/No Mode". The FC was trying to level the quad while the motors were running. Again, thanks Pawel for broadening my knowledge and saving my fingers. :D

[@sunsetpark_fpv]

Wow thanks for the spreadsheet Pawel!

[@igort5418]

That's looks very safe.

[@MCsCreations]

Well... The way he did it the PID loop was off. So, the quad won't do anything stupid. The rest is up to you. 🤷‍♂️

[@olafschermann1592]

AWESOME! 2 very simple methods to get accurate readings and therefore predictable power consumption readings. I tried to figure out how i could get resistance: slowing the motors by hand or soldering a power resistor - but just reversing the props - how simple (and relative safe) is that! Smart! Thank you so much. Servus aus Wien!

[@ellingolsen3194]

Small props are less scary than large props. I use 3-inch props - reversed.

[@miroslavjankovic4012]

can you tell me what amount of throttle should I aply when using clamp meter?thank you

[@MCsCreations]

Fantastic tip, Pawel! Thanks a lot! 😃 I have the exact same clamp meter! Anyway, stay safe there with your family! 🖖😊

[@maceliusfpv370]

The reading is always pretty stable on my clamp meter, or running through my normal meter (which does up to 10A) for micros, but in betaflight it jumps around so much it's hard to estimate the mean, or even median.

[@pierce0690]

keep up the good work comrad

[@zsolezk]

Does this meter work for small 1S batteries also?

[@swgar]

Even in AC mode clamp meters are sensitive to cable location. DC mode works not with a transformer but with a couple of Hall sensors and they are affected by cable location way more. What you show on 4:30 looks completely wrong, so it could be that you even made your calibration worse. I don't have such a DC clamp meter on hand so I can't tell exactly which error is achievable by incorrect use, but 30 % looks doable.

[@typxxilps]

A shuntmeter should also work but then the batterycable woulf have to run through that shunt while emulating the flight on the bench to get the full power consumption. Great explanation - thanks a lot.

[@J2_P]

Why not use bench power supply with current display :)? Or more easily a charger in power source mode (they also display current consumption)?

[@spaceportseven]

Depending on throttle position on my wing the values go out of accuracy as throttle is increased beyond the testing value used Using the ammeter method. Do I need to set the offset option ?

[@ellingolsen3194]

Setting both scale and offset is a totally different ballgame. For simplicity set offset to zero. If the Amps displayed are far too high when unarmed, then you probably have noise on the current sensor signal. That must be fixed first!

[@mr.saleprot6217]

if you have calibrated the sensor, then there is a change in esc. does it need recalibration or not? Thanks pawel.

[@FPVUniversity]

No, you calibrate the sensor, not the ESC. If you change the sensor, then you have to recalibrate it

[@rougeneon1997]

I cant recommend the "Toolkit RC" watt-meter enough. the servo/esc tester signal out function is really useful as well. It has a 150 watt peak use. Good vid. I usually have trouble calibrating FC shunts because the value works rite at one "point" of throttle but not necessarily the other. Like cruising vs idle

[@sabyco92]

good video Pavel well done !

[@shuraim8675]

Thanks a lot mate, well explained. Subbed 🙏

[@kool-k-kel]

Thank you very much! excelllent vid as per usual!

[@ellingolsen3194]

Pawel, I have been experimenting with a method where I make two accurate measurements, one at low RMP and one at a higher RPM. I put the two sets of data into a spreadsheet that calculates values for both Scale and Offset. What I use is a ToolkitRC M6D and possibly also a 100nF capacitor to filter the current sensor signal. Do you need this kind of accuracy? Probably not, but it can be done and I find the result amazing. I am not going to make a video about it, but you can if you are interested.

[@SId0rich]

1.Is it Icarus on tshirt? 2.What if current sensor values depends on choosed ESC protocol?

[@FPVUniversity]

1 - yes! 2 - they do not

[@sladelefty]

I use a motor watt/volt/ampere tool for rc airplanes. Very easy and accurate.

[@fractalengineering]

I did the first one before and it's terrifying lol

[@maceliusfpv370]

Strapping it down helps, cover with a laundry basket if really worried lol.

[@FelixLeForestier]

Didn't know Pawel was also a stuntman

[@lucaswybrandt7058]

If you only have an AC clamp meter would it then make sense to measure one out of the three motor wires and multiply it by three and then by four to get the total motor power consumption. The motors consume almost all of the power so wouldn’t it be a realistic to compare the total power consumption with the motor power consumption?

[@Tobi-xj8xw]

A ac only meter may not measure it correctly because our rc motors don't run on ac but on switched dc(pwm). If you use a scope you would see a square wave not a sinus wave like mains ac

[@lucaswybrandt7058]

@@Tobi-xj8xw I’m pretty sure that’s not the case. The PWM signal is only used to control the ESC. The output of the ESC I a sine wave. That’s how you drive BLDC motors. They need AC to run. The ESC is generating the AC signal with a bunch of mosfets to make it capable to output both positive and negative voltages just like an inverter

[@Tobi-xj8xw]

@@lucaswybrandt7058 haven't seen your comment until now, sorry First The motors er use in the hobby are synchronous motors so let's say we connected the motor to a 3 fase outlet(bringing down the voltage with a transformer) the motor would not run. 3 fase ac motors are asynchronous motors Second There's a difference between the pwm we use for servos and speed controllers and Pwm used for motor control. The pwm we use for servos is measured with micro seconds and how many refreshes per second measured with Hz The pwm used for motor control is measured in duty cycles Edit: the example below would be for a brushed dc motor for a 3 fase bldc motor the plus and minus would switch like First fase + secend Fase minus third fase nothing First fase nothing secend fase + third fase - First fase - secend fase nothing third fase + A duty cycle of 50% and would mean it would be on for halv of the time then off the other half, effectively halving The voltage

[@lukaszfron]

9:25 Actually I do not agree with you Paweł. Of course some energy is being lost as heat during discharging and recharging. But it's energy not electric charge. To be precise, some electric charge is lost but it's negligibly small. Some charge can be also lost in balancing module in the charger is poor quality. However, most of energy is being lost due to voltage drop on battery's internal resistance.

[@JGM_FpV]

Witaj Paweł suoer kanał, ale dlaczego nie nagrywasz po Polsku również tych samych filmów :((

[@FPVUniversity]

kzbin.info/www/bejne/onqmnZl_q6akkLc

[@JGM_FpV]

@@FPVUniversity Dzięki wszystko jasne z jednej strony można się uczyć angielskiego lub włączyć napisy po Polsku w YT rozumiem, że tak bardziej dociera się do większego grona subskrybentów lecz liczba osób zainteresowanych dronami w Polsce wciąż rośnie, a dzięki takim kanałom jak Twój( bo robisz widzę super robotę) gdyby były nagrywane również w ojczystym języku było by nas pewnie więcej. Można przecież jak np. Klawiter zrobić drugi kanał choćby na próbę po Polsku i zobaczyć ilu nas będzie, po angielsku jest tego masę Joshua, Nurk itd. I nie żebym naciskał każdy ma swój wolny czas chęci itp. w pełni Cię rozumiem tylko po prostu szkoda :((

[@babyfpv2845]

looks like not good idea to hold hand so close to propps....

[@TheMadmacs]

ahhhh sneaky, i like it, i sorta know how much mah's i put into my packs, they are cheapos so i'm keeping a close eye on their health.

[@IDoAgri]

You sure like Sliced bread! haha

[@juhaszjanos7770]

Ikarus!