Mesuring banana clips in a quadcopter for voltage

hello guys i am trying to mesure the Voltage from my ESC to motor. the voltage is -0 and i dont know why.

i have pulled a bit the banana clips so i can insert the black red stick and mesure the voltage but for some reason its not working.

i am not sure which from the three bananas i must mesure so i am testing this to every possible combination.

any ideas? Why its not working…

thank you

I would suspect that the ESC is not powering the motor.

I have no experience with ESC but looking at the connections, it looks like you have the battery pack connected via heavy wire and the red wire connected to the Arduino. The black wire is connected to the green jumper that is not connected to the Arduino. It looks like you have no Gnd connection to the Arduino.


the green is the BEC its not a problem and the motor was spinning before the img was captured. these is something else....

You have a brushless motor there. Many times per revolution, the ESC will energise each coil in a positive direction and a negative direction. The average is zero. You could use the AC scale on the multimeter to get an idea of the voltage, but it won't be very precise.

You would need an oscilloscope to see the waveform and perform calculations on the waveform to get a real value that the motor is seeing.

Banana plugs, banana jacks. Not clips.

@MorganS you sure about that? I am asking because this things are a part of my msc paper, its not only my hobby.

Brushless motors with 3 wires are basically 3-phase AC devices (roughly speaking), driven by a 3-phase bridge that may have PWM active on high-side or low-side drivers or both. The tool to look at the output is an oscilloscope, time-averaged voltages will not be informative.

thank you for the analysis @MarkT


msc paper


Tom..... :)

paper is called the pdf with your all work that you will publish at the end of your master. Mine is about quadcopters and failsafe systems.