weird motor noise after changing hall sensors.

[Sigma]

Hi, alright so I have a weird noise after replacing the hall sensors on the hubzilla motor after blowing my old one. Right off start under load, It makes a weird noise like its going to stall. If to much load is on the bike and I don't give it abit of a push it will stall. This only happens during the start and goes away awhile riding. But if no load is applied it does make the weird noise. This wasn't a problem before I replace the hall sensors. Was wondering if anyone knows how to fix this. Ill post up a video when I can.

Hydro-one also has the same problem as me and he thinks it has to do with a bad phase wire or something.


edit: videos below

[youtube]bS2rgu3NXj0[/youtube]

[youtube]N2WjiXDm1dU[/youtube]

 

[dogman dan]

Test the new halls of course, but also look really hard at your plugs and make sure none are backed out of the housing or bent.

 

[hydro-one]

Hey I have the same problem, seems to me like a slightly damaged mosfet?? It appears to be a hall problem, like a backed out wire. but its not. This only started on sigmas bike after a spinout where a phase wire contacted the hall red wire and blew all the halls. Could this have sent a bad signal to the mosfets and possibly damaged one? Its like one phase wont hold any amps.I had this same sort of issue before and it was a melted solder connection in the motor (phase cold joint, oh the humanity). But his motor is new, never been hot.... So im thinking a mosfet, measures ok but has some kind of damage .......would a scope help determine this?

of course the answer is to swap controllers, and see if it changes...........

 

[amberwolf]

A scope may show a problem. If you look at my powerchair motor thread, I did some scoping around on the phases after I managed to have my opened-up controller land on a pair of needlenose while in operation.
http://www.endless-sphere.com/forums/viewtopic.php?p=514879#p514879
There's a vid there somewhere of the phases afterward, and you can see they don't look the same--only one is exactly like it used to be.

That controller still works after repair, but it acts oddly, as if a phase (or hall, or both) isn't working quite like it should, and sometimes it won't start without a push on the motor.

 

[dogman dan]

By the time you have hubzilla money in ebikes, it's time to have your motor controller throttle tester. Best 30 bucks I ever spent on ebike stuff.

 

[Sigma]

Hey, so would you suggest that it has something to do with the controller? I wonder if a new controller would help.

 

[dnmun]

did you test the hall sensors after you replaced them?

did you measure the resistance across the mosfets?

richard has a thread on this in the technical section, but you wanna use an ohmmeter and measure the hiside mosfet resistance between the big red wire and each of the phase wires, then measure the loside mosfets by measuring the resistance between the ground or black wire and each of the phase wires.

of course you can just buy all new without testing too.

 

[Sigma]

Hi, would you happen to have a link to the to the other thread, endless search function is really crappy.

 

[dnmun]

nope, thought i could find it in the technical reference section. but it is pretty straightforward if you have an ohmmeter. just 6 measurements for the mosfets. and 3 measurements for the hall sensors.

the hall sensors have to be measured at the 5 pin plug which i assume you already know how to do since you said you replaced them so you hadda figure out which was dead before. so just test them again to be certain they work now.

 

[amberwolf]

By the time you have hubzilla money in ebikes, it's time to have your motor controller throttle tester. Best 30 bucks I ever spent on ebike stuff.

IIRC, that controller I damaged, which still doens't work quite right, works fine according to the tester.

 

[dogman dan]

That's not good. I suppose the tester would only indentify a phase wire with no current. Still a handy tool for that at least.

 

[John in CR]

By the time you have hubzilla money in ebikes, it's time to have your motor controller throttle tester. Best 30 bucks I ever spent on ebike stuff.

IIRC, that controller I damaged, which still doens't work quite right, works fine according to the tester.

I never bothered trying to use the tester to test a controller, after I almost started a fire with a bad controller trying to test it. Instead, I use tester to verify the throttle is fine, and that the motor and halls are fine. Then the motor becomes my controller tester.

WRT to the thread topic problem, I'm sorry, but I can't help.

John

 

[Sigma]

xD is there a guide anywhere on how to use the tester, Im still a noob at this lol. I checked the resistance from black and red to the phase wires all are okay its resistance starts at about 10k and goes up to like 20k. So not sure what the problem is, I tested my hall sensors before I put the motor back but Ill test again to make sure its working fine.

 

[dnmun]

do the hall sensors toggle on and off? there is no need for the lyens tester to establish if the halls work.

just three measurements of the hall sensor output when you rotate the wheel and you will know if the problem is in the motor or the controller. same as you did when you established that the hall sensors were dead before.

 

[Sigma]

Hey, halls works perfectly fine. They toggle from 0 to 4.** volts. Still cant determine what the problem is.

 

[dnmun]

measure the output mosfets with an ohmmeter. measure hiside FETs between the big red wire and each of the phase wires and the loside between each of the phase wires and the black wire to the controller.

 

[Sigma]

Im pretty sure I did that already and got a range of 10k ohms to 20k ohms depending on how long I keep the leads on there. Does high side mean the right wires and low side mean the black wire?

 

[dnmun]

yep, so the noise is not from electronics failure. plus you had trouble getting it to start up as a sensored motor should too. which was why i suspected the halls. i'm stumped. keep bumping until someone sees this and has an idea. BOL

is it possible something is rubbing inside? maybe bad bearing or not seated properly in the cover?

the output mosfets are hiside if they are the ones above the phase wire and loside if they are below the phase wire.

 

[amberwolf]

The problem could still be hall-related, in that a hall input to the MCU inside the controller might not be receiving or responding to the hall signals from the motor. Such a problem could lie anywhere between the motor/controller connector up to the MCU pins themselves, but because you get the 4.xV on the halls, is likely to be closer to the MCU than the pullup resistors (if these are in your controller rather than the motor).

 

[Sigma]

here are the videos showing unload and load test and a test run.

[youtube]bS2rgu3NXj0[/youtube]

[youtube]N2WjiXDm1dU[/youtube]

ps: if you need me to record anything else that may help, please let me know.

 

[dnmun]

usually the 5V rail runs out to the hall sensors across the bottom of the pcb and it has a TVS to protect the board against the hall leads shorting to high voltage. you said this had happened to you and was why you replaced the halls.

i am not sure what to expect if the TVS was damaged, maybe someone has an idea, but it may not be allowing enuff current now to let the halls signal normally. just a guess.

take close up of that area including the hall sensor resistors too. maybe we can see something. and you could jumper the TVS to see if the behavior changes.

 

[Sigma]

Here are the links to the images. Not sure exactly where to take the picture on the board. I took a pic by where the halls were.

https://www.dropbox.com/s/f8hoe4lg8jon7yw/DSC01207.JPG
https://www.dropbox.com/s/h9hupfsu9ex8ite/DSC01208.JPG
https://www.dropbox.com/s/zqdyzohk9ccmnhc/DSC01209.JPG

 

[amberwolf]

I would expect that if the TVS was damaged in the usual way they fail, and the TVS is wired parallel to the 5V supply, the 5V line would be shorted enough to prevent the controller from running properly, if at all, and you'd get no wheel movement or other response from it.

If it failed open, then probably you'd still have normal operation of everything, except there'd be no protection for "next time".

I suppose it might be possible for a partial-failure condition, but I imagine that all the 5V lines are tied together and any dragging-down it does of the 5V would do the same as a full short, and also prevent anything else on the 5V line from getting enough voltage to operate correctly, but I guess it would depend on the other circuit components and if they can operate better at lower voltage than the halls could.


That motor under load sounds like a false positive combo sound, or when a hall is not connected.

If you can set it up so the controller can't short against anything but is powered on, you might want to measure the hall signals in operation (wheel off ground, hand-spun) at the controller PCB itself.

 

[Sigma]

Im not sure what you mean "at the controller PCB itself." I've tested the halls at the black/red leads vs the other colors for the halls hand spun and the readings range from 0 to 4.** just fine :S

 

[amberwolf]

I mean that (as I tried to say in a previous post), if the hall signals don't reach the controller's MCU, it doesn't matter if they work at the wheel or at the connector to the controller.

So while you have the controller open, you could check the hall signals at the actual controller internal connections. First where the wires are soldered to the controller (and then if possible tracing where those end up going to the MCU pins themselves, though it is unlikely there would be a problem beyond the wires that you could detect this way).

If you have already measured them like that, I apologize for misunderstanding.

If there is no damage to the electronics of the controller (which you may not be able to determine, if the problem is in the MCU itself), then the only other thing I can think of is that the wiring combo on the halls is incorrect vs what it used to be. This could happen if somehow the leads were resoldered to new halls in a different order than they were before.