Testing hall sensors INSIDE hub motor (bafang)

Hey guys, can you please just confirm that I am checking the hall sensors the right way - inside the motor?
As you can see from the pictures I cannot tell which colour is which sensors - therefore I have no way of knowing which to replace..

How do I test it inside? I have measured from the board to where the cables connect to the hall sensor. Is this right?


Also could anybody tell me what is the function of the thing I have circled in yellow?? It seems to be broken..
Thanks a lot!

I can’t tell what that is in your picture.

Here’s a thread which discusses and demonstrates how to test motor Hall sensors without relying on or using the controller.

https://endless-sphere.com/forums/viewtopic.php?f=3&t=57053&hilit

Ykick said:

I can’t tell what that is in your picture.

Here’s a thread which discusses and demonstrates how to test motor Hall sensors without relying on or using the controller.

https://endless-sphere.com/forums/viewtopic.php?f=3&t=57053&hilit

Click to expand...

Where exactly?

I reposted what I provided that user who seemed to figure it out. Sorry, I'm not better at describing what needs to be done but TBH it's fairly obvious.

Here's a simple test rig to remove possibly faulty controller 5V from the circuit for the time being:




5V Red+/black- power arrives from a wall wart (or battery) to motor Hall red/black. 10k resistor connects from 5V red+ to one of the motor Hall switch wires (green in photo) along with the + lead to the meter. Or, you can use an LED instead of the meter which is what the eBike motor/controller tester does.

Rotate the motor and hopefully observe switching between 0-5V. Repeat for the remaining Hall signal wires.

It can be noted that most motor Hall sensors handle up to 30V. 5V isn't really that critical, you can use a 9V battery or pretty much anything between 5-30V. I merely use 5V because that's what the controller supplies to these circuits.

What you're doing is merely qualifying motor Hall wiring and Hall sensors. Since you describe the controller 5V pulling down when connected to the motor I suspect a fault inside the motor.

And/or, it may also be a faulty controller? But doing this test will help determine if you need to go back into the motor for further rework to the wires and possibly Hall Sensors.

If the motor Hall sensors end up being bad you could possibly try a sensorless controller if the motor phase wires aren't shorted? Myself, I would just opt to replace the sensors and wiring inside the motor.

But first thing is isolate where your problem(s) happen to be.

Here are a couple of high res pictures of the sensor board:


The part you circled contains two capacitors and a resistor. I'm not quite sure what their function is in this circuit but they appear to only be for the speed sensor which isn't installed on sensored models.

I see burned marks near one of the electronic component labeled as C5. It's a capacitor. If it is shorted, it may redirect voltage from the red wire (+5V) to the hall signal wires, which render voltage to stay at +5V. I'd suggest to verify continuity or resistance between both ends of the C5 capacitor.

Yes, it is capacitor definitely that is smoked. Is there a way to repair it? How? I am now pretty sure that is the problem, and the hall sensors are fine..

Can I just solder in something like this - http://www.maplin.co.uk/p/15f-5v-super-capacitor-module-n54qq or this - http://www.maplin.co.uk/p/0047f-55v-double-layer-capacitor-n98cn ??

Looking at flangefrog's pictures, and his comments about a speed sensor, I am thinking you're going down the wrong path replacing the C5 capacitor. It's hard to tell, but I suspect to me that whole subcircuit with R1, C1, and C5 is not doing anything in this application. The S443F device in flangefrog's picture is not on your board. I can't see any connectivity to the Halls, although those components may connect to power and ground.

A better picture of your board would help. This guy has some great pics. http://www.etotheipiplusone.net/?p=2799. A good pic will allow people to reconstruct the circuit and provide better advice on how to test it.

OK, suppose you really want to replace C5, what's its value? Next, how will you get the epoxy off?

docw009 said:

Looking at flangefrog's pictures, and his comments about a speed sensor, I am thinking you're going down the wrong path replacing the C5 capacitor. It's hard to tell, but I suspect to me that whole subcircuit with R1, C1, and C5 is not doing anything in this application. The S443F device in flangefrog's picture is not on your board. I can't see any connectivity to the Halls, although those components may connect to power and ground.

A better picture of your board would help. This guy has some great pics. http://www.etotheipiplusone.net/?p=2799. A good pic will allow people to reconstruct the circuit and provide better advice on how to test it.

OK, suppose you really want to replace C5, what's its value? Next, how will you get the epoxy off?

Click to expand...

Ok, one more picture. you are right that S443F is missing. However, I am sure that it was not there in the first place- when I took it apart. Why could be that? Also, I now C5 capacitor was burned when I opened it up, now I took the epoxy off on the part and the capacitor C5 just fell off - I tried to solder the part together so as to make circuit there without capacitor, but no surprise the motor did not run..

can you just buy another motor?

docw009 said:

Looking at flangefrog's pictures, and his comments about a speed sensor, I am thinking you're going down the wrong path replacing the C5 capacitor. It's hard to tell, but I suspect to me that whole subcircuit with R1, C1, and C5 is not doing anything in this application. The S443F device in flangefrog's picture is not on your board. I can't see any connectivity to the Halls, although those components may connect to power and ground.

Click to expand...

Actually I had another look at the rear of my board and the capacitor may actually be a bypass capacitor between the power rails.

davidsvoboda said:

Ok, one more picture. you are right that S443F is missing. However, I am sure that it was not there in the first place- when I took it apart. Why could be that? Also, I now C5 capacitor was burned when I opened it up, now I took the epoxy off on the part and the capacitor C5 just fell off - I tried to solder the part together so as to make circuit there without capacitor, but no surprise the motor did not run..

Click to expand...

The S443F is only on the sensorless versions for speed sensing. On sensorless versions the side plate has six magnets embedded in it for the S443F to pick up.

Also, if the capacitor is blown - what is its function? Could I not buy cheap sensor less controller and would that not work??

Or add the ss443f thing and run it sensor less afterwards? How does sensor less work? is it without hall connectors?

Try removing the capacitor, because if it's a bypass capacitor it may be shorting the power rails. Have you tested that there is 5V and Gnd at the halls? (not at input to board).

You should be able to run the motor with a sensorless controller however since it's a geared one you want a controller that can start the motor from stopped. I.e. not the Golden Motor controller which I've been using with mine. The S443F sensor isn't needed for sensorless operation, it's just to get feedback for what speed you're going and for speed limiting. It won't work without also installing the magnets.

You don't need the board, many motors don't have one. The main function will be to hold the sensors in place. You could wire them up without the board or cut all the traces and just use it for holding the sensors. If you need to replace the halls: https://endless-sphere.com/forums/viewtopic.php?f=30&t=72393&start=25#p1109366

So can anyone explain how would it work with a sensor less controller? Do I need to do anything? I have replaced the capacitor already, but the motor stopped working altogether.. :/


Also, any suggestions for a sensor less controller?

thx

on a board that doesn't have a S443F sensor and only one magnet in the cover.
What creates the signal?
How can i test that signal as i have no speed or odometer readings on the clock.

What specific motor, controller, and display do you have? More detail on the system is better to help us help you.