Transcription: Brushless motor testing with an Oscilloscope - YouTube

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Hello, everyone welcome back to another video.

I did a video a while back, showing how you can test a motor using an oscilloscope.
If you don't have an LC meter and today I want to show you what a broken motor looks like when testing it on the oscilloscope, because last time I didn't actually show, I showed how good motor looked, how the waveform should look and I'm going to show You how a broken motor looks so what we have here is quite simple: we've got a broken motor.
This one has got a lot of damage it completely fried and I've just taken it and put some n3 nuts in the bottom or bolts in the bottom.

At least and attached to the vise and then the vise goes on top of the drill, press and I'll just extend the wires here, which I can then attach to there.
So, let's go probes to make a little bit more robust, let's say, and then I'm just gon na attach this.
So let's get to that now! Okay! So after a lot of messing about with the settings, I had some problems with the acquire.

I was in the wrong thing.
I was using some averaging.
That's why I kept dropping down so nevertheless, here we are what I've got here.

Is the motor attached to the oscilloscope, I'm not sure which of the coils or how many are broken in that motor? I just know that it's completely fried later on, we can open it up and take a look if the findings match up with the reality of.
What's inside the motor anyway, we have channel 1 2 & 3 they're all set to 500 millivolts per division, so each one of these squares represents 500 millivolts being generated.
If the wave gets to that point and I'm going to start the drill press now and let's see what happens, it's gon na give it good.

So what do we see here? We see remember they're, all the same they're running on the same heights.
Essentially so we should, in on a good murder, you'd see that all three peaks are the same height, because all the coils are the same.
But what we see here is that one of them is high.

The purple one Channel three and the other two are low.
So my assumption is that these two channel one and two so two sets of coils are actually burnt out, because what would happen is that these ones are shorting out, because the insulation burned up it's not as though that coil actually burnt away.
They are still making contact and they are still working as such as coils, because it's still spinning and creating magnetic field, but because the coils are shorted out, they seem to be much, let's say, shorter, shorter, meaning that they have less windings to create the magnetic field Which would make the power in this oscilloscope example? And, conversely, when attaching an ESC or speed, controller and running the motors, you would then not have as much power running through them and, despite that, they're actually burnt out so which means that just having one solid piece of copper and said of all the windings which Create the magnetic field - that's the assumption, at least so here, and you see this pretty picture there now channel 1 and 2 and our 50 millivolts per division.

Channel 3 is still at 500 millivolts per division, showing that we have a 10 times less magnetic field being generated by the first two coils, as opposed to the third coil right.
I think next would be to look inside the motor.
I mean if you expected, just to not see anything beam generates at all.

That's not the way it works, because it's still it's still creating a magnetic field when it spins.
It's still doing that.
It's just on a much lower level on a much smaller amount because of the fact that the coils have completely burns out and therefore they have less windings, essentially inside them to make the magnetic fields which will either spin the motor or, in this case, generate the Power that comes out of it, so I think next we can actually open up the motors and see if those findings match up strong magnets in these motors.

What we have here is a mess, so we have these two coils completely burned, and now I think we can actually trace which ones those belong to so number one.
So if we recall well today, we have it.
Dad is what a motor looks like when on the oscilloscope, when the coils are all wet a bit.

That's what a burns have motor looks like on the oscilloscope, repeating the same test as last time, which I did with a healthy motor.
Now you've seen it with an unhealthy moto.
So thanks for watching and I'll see you soon on the next video you .


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