Vevor Motor grinding sound

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zakkyzebra   1 µW

1 µW
Posts: 1
Joined: Sep 21 2022 7:42pm

Vevor Motor grinding sound

Post by zakkyzebra » Sep 22 2022 9:39am

Hi, I recently ordered a 2000W 48V DC Brushless Motor & Controller Kit from Vevor.

Motor model : MY1020D
Controller model : BY15WF02-A

The kit went together fairly easily, all the wires went together by color and it went in reverse, researched it might be a hall/phase combo, messed around a bit and switched the hall sensors on the motor and switched the phase wire combination to the following:

Motor | Controller
B | Y
G | G
Y | B

Motor | Controller
B | B
G | Y
Y | G

and that was it, I was scooting along on my homemade EBike. Yay. For about 30 minutes. Then whenever I gave the system throttle, it would make a grinding type sound and come to a halt. I immediately stopped and felt the controller, hot to the touch, motor pretty warm to the touch not as hot as the controller. I proceeded to pedal home to try to figure out what went wrong.

Assuming that the controller was toast, and wanting an upgraded controller anyway, I ordered a KunRay 48V-96V 80A 3000W controller. I THINK the model number is : KRBLC0 1014, not entirely sure.

I wired it up according to the store's suggestion at:

Motor | Controller
Y | Y
B | G
G | B

Motor | Controller
B | Y
B | Y
G | G

I then connected the selfstudy wire to itself and the motor started spinning in the wrong direction, according to the advice from the company, I unplugged it and plugged it back in and it started spinning the correct direction. I let it run for 10-20 seconds, also according to the company, then unplugged it (you guessed it, according to the company). I then gave it some throttle WITHOUT the tire connected via chain and it seemed to run fairly smooth, sometimes jumping backwards then smooth forwards depending on how it felt. But once I connected the tire to the motor, all heck seemed to break loose. It will sit still with no throttle, cool. Give it some low throttle, the tire jumps around a bit then goes, gives it slightly more throttle, HORRIBLE grinding sound and tire comes to a halt. Manually pedal the tire to make sure its not mechanical, all seems good. I am pretty sure I tried out all of the phase/hall combos (forgot to mark a few off when going through them) and all of the combinations have the exact same results.

I then read that it might be a motor issue itself, which I assumed would be fine as it wasn't sweltering hot as the controller was. So I cracked that bad boy open and with my vast superior knowledge (i have no clue what i was looking for) I came to the conclusion that it didn't look melted. so that's good right?

And this is where I am at right now. A complete and total loss as to what the issue could be. I don't have another motor to test this controller on at the moment, but I have a voltmeter and know how to follow directions. Any and all advice is appreciated.

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amberwolf   100 GW

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Re: Vevor Motor grinding sound

Post by amberwolf » Sep 22 2022 10:41pm

Given the symptoms and test results so far, the most likely problem is in the motor or in the connections between the motor and controller.

If there is a problem in the connector itself for phase wires, it could have a high enough resistance to prevent proper driving of the motor under sufficient load, while working alright under no-load testing especially at lower throttle or during automatic setups.

Similarly, if there's a hall connector problem, they might be read well enough at low load, and not at higher ones, because of electrical noise generated in the phase wires that are probably bundled in the same cable with the hall wires.

It can also be melted insulation inside the cabling (anywhere between motor and controller, but given the controller's been changed but problem remains, it's likely in the motor half of the wiring), such that there is a low enough resistance *between* phase wires that when the load is low or throttle demand is not high, it works ok, but when more voltage is placed on the phase wires from higher throttle demand the signals begin to short across from wire to wire.

FWIW, a timing problem, or problem reading the hall sensors, can cause sudden reversal of the motor direction. It can be from an actual sensor problem, a wiring or connection problem, or even from electrical noise in phase wires induced into the hall wires. (that can be fixed often by separating the hall and phase wires by some distance, for as much of the path between motor and controller as possible).

If it were only having a problem once it heated up, I'd suspect an actual hall sensor problem, damaged from heat already, then showing the problem again the warmer it gets (but working ok when it cools down).

FWIW, whenever I've found a controller heating up more than the motor, it's been because the controller doesn't have enough airflow, or the phase/hall combo is wrong (not the case here, given your testing so far), or there's a problem with timing or connection between controller phases and motor phases, so currents flow incorreclty inside the controller and it heats more than it should. Or the capacitors in the controller are insufficient or faulty, and aren't filtering the electrical noise correctly so stuff isn't operating quite like it should.

Since the motor is where the load is at and the heat is usually generated, it should typically get hotter than the controller (but not really hot if it's correctly sized for your load and usage, and the controller should not get hot (warm, but not hot).

FWIW, there have been a few threads using Vevor kits, with mixed results. The following search is just for any thread that contains the word Vevor, so it could be narrowed down quite a bit for more useful results, but the list is pretty short so shouldn't take much time to poke thru if you're curious. :)
search.php?keywords=vevor&terms=all&aut ... mit=Search
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