Salvaged Zero FXS motor converted to hall sensors

[trazor]

I've got a salvaged ZForce motor, without controller. This motor seems similar to http://motenergy.com/mepmbrmo.html

These motors are controlled by a sine/cosine encoder instead of hall sensors and the controllers capable of drive them are > 800 usd.
I wanted to try the motor with the only available controller I've now: a cheap no brand golf kart sized one. So, decided to install hall sensors and learn a bit the process.

I'm a complete noob and had to read these before start:

https://www.motioncontroltips.com/faq-what-are-hall-effect-sensors-and-what-is-their-role-in-dc-motors/
http://mitrocketscience.blogspot.com/2011/08/hall-effect-sensor-placement-for.html
https://www.rcgroups.com/forums/showthread.php?1556916-DIY-Brushless-DC-hall-confusion
https://www.instructables.com/id/Make-Your-Own-Miniature-Electric-Hub-Motor/
https://www.nxp.com/docs/en/application-note/AN4776.pdf
https://www.youtube.com/watch?v=WobfIjmNJrk

And then started to execute:


Ad hoc tool to extract the rotor

Note the 3d printed cap to not damage the sine/cosine sensor magnet

View attachment 8
3d printed hall "tower"

View attachment 6
View attachment 5
View attachment 4

All looks ok on the 15usd motor tester (sorry, no oscilloscope here)
View attachment 2


Made "slots" to adjust the timing


After finding the correct cable phase/sensors combinations, the motor spins at 3000RPM, 80v, 6Amp no load. Does these figures look ok?

 

[amberwolf]

Sounds reasonable, though you can probably check in the thread (by Methods? DoctorBass? cant' remember) about the Zero motor testing. I don't have link but it ought to be easy enough to find.

FWIW, I used a slightly different method to add halls to a SIN/COS motor:
https://endless-sphere.com/forums/viewtopic.php?f=30&t=32838&start=25#p504935
and it appeared to work, though I have not gotten back to it in a long while, to actually test it on a bike. I really want to....

 

[fechter]

6A sounds about right. Nice work.
Timing will make a big difference. You can adjust it for the minimum current at no load and it will be pretty close. From there, it should be advanced very slightly.

 

[Emil.S]

Nicely done with the 3d-printed adjustable timing!
I'm about to do the same but on a Motenergy me1616(sin/cos encoder) together with a KLS96601-8080H that only accept hall sensor input.

I'm just wondering which type of hall sensor you used, latching?, non latching? unipolar?

 

[fechter]

The most common motor hall sensors are bipolar like a SS41. Many types will work.

 

[trazor]

Nicely done with the 3d-printed adjustable timing!
I'm about to do the same but on a Motenergy me1616(sin/cos encoder) together with a KLS96601-8080H that only accept hall sensor input.

I'm just wondering which type of hall sensor you used, latching?, non latching? unipolar?

Thanks pal.
I'm very uneducated in electronics and only know the hall sensors of type: switch, latching and linear. I think all hall sensored motors use the switch type. Linear are common for throttles and never saw a latch type on an e-bike.
The ones I got are https://alhkma.com/04e-a1104-magnetic-hall-effect-sensor-digital-switch/

IRC I have the printed part in autodesk inventor format if you want it (will require modification for sure). I've printed the part in ABS plastic. PLA isn't going to hold above 70 celsius.
If you make it post pictures and crosspost here so we can find it easily. Good luck.

 

[Robinev]

I contacted John Fiorenza from montenergy. I have a me 1507 sine cosine encoder he gave me the exact replacement part number. So the same magnet in the center will work with a 3mm spacer. It even has a option to have molex to use existing cable good luck
https://www.rls.si/eng/rmb29-rotary-magnetic-module
Part Number RMB29EE12BS66

Choose:
1) Commutation single end
2) 5 periods per revolution (10 poles).
3) 4096 points per revolution
4) Square
5) Push-Pull UVW with Molex

Once you get this sensor circuit board, you may need to set the air gap to 3 mm with some shims, and then "time" the motor by rotating the position until it commutates properly.

 

[Dui ni shuo de dui]

Is there some kind of way to convert this motor to hall sensors without having to open it?
Like adding some kind of circuitry that could convert the sin cos position into hall sensor outputs?

 

[fechter]

Converting sin/cos to a simulated hall output seems possible in theory but I haven’t seen a circuit that does that.
If the little sensor magnet has the same number of poles as the motor then I have seen a hall sensor setup that could work like that. The newer BBSHD motors are like that with a 3 hall sensor chip right on the board and a little encoder magnet on the end of the shaft.

 

[amberwolf]

There's some discussion about that in an old thread, including this post by Alan B
https://endless-sphere.com/forums/viewtopic.php?f=30&t=32838&p=486271

this one also
https://endless-sphere.com/forums/viewtopic.php?f=30&t=110250

 

[TorgueRPM]

From what I remember from when I opened up a qs 138 mid drive motor, they use a sensor magnet with the same number of poles as the motor and then a hall circuit that is accessible without opening up the whole motor. It's just behind a cap by the non-drive end of the shaft.

 

[Doctorbass]

I am also converting my 75-5 from a 2013 XU to hall sensor and also will rewind it to 74V. I will use it on my bac 8000 at full 860 pA

Doc

 

[larsb]

From what I remember from when I opened up a qs 138 mid drive motor, they use a sensor magnet with the same number of poles as the motor and then a hall circuit that is accessible without opening up the whole motor. It's just behind a cap by the non-drive end of the shaft.

Yes, that’s correct, could be done like that or with separate switching magnets on a carrier mounted on the rotor. I did that on my revolt motor, worked well.

 

[liveforphysics]

Nice job with the halls, I hope you don't mind I may copy that trick when I need to.

 

[spinningmagnets]

Well done. Thanks for posting this!

 

[Solexelec]

I contacted John Fiorenza from montenergy. I have a me 1507 sine cosine encoder he gave me the exact replacement part number. So the same magnet in the center will work with a 3mm spacer. It even has a option to have molex to use existing cable good luck
https://www.rls.si/eng/rmb29-rotary-magnetic-module
Part Number RMB29EE12BS66

Choose:
1) Commutation single end
2) 5 periods per revolution (10 poles).
3) 4096 points per revolution
4) Square
5) Push-Pull UVW with Molex

Once you get this sensor circuit board, you may need to set the air gap to 3 mm with some shims, and then "time" the motor by rotating the position until it commutates properly.

Hi i have the same plan like you.
Replace sincos board by uvw.
Can you make the conversion? It's work?

What do you think when you Say to "time" the motor