Ezee motor cutting out

[wehey]

Hiya all.
Just after your opinion on this issue I have.
I have a rear Ezee motor, Ezee 25Amp controller and 48v battery.
The motor cuts out when I pull away giving it full throttle. The wheel starts to turn then after about 0.5 to 1 revolution it stops. There is still voltage at the inline power meter so I don’t think it’s the battery.
I have checked the Ezee controller and it flashes 8 times which means a hall sensor fault.
The rest of the time it rides just fine, climbs hills like a beast, and as long as I accelerate off the line gently it works faultlessly.
So is it likely to be a hall sensor in the motor at fault or could a dodgy hall sensor wire/connector cause this.
Thanks in advance.

 

[amberwolf]

Does the voltage drop during the acceleration? By how much, if so?

If it's enough of a voltage drop, the controller could hit LVC and shutdown, then the voltage will bounce back, which is the voltage you'll then read if you only check after the event. THis is probably not the issue since it works on hills, which would have voltage sag under load similar to acceleration from a stop.



For the hall error, you can check first the connections, and cables. If you find no mechanical problem to fix, then you can perform the hall test per the ebikes.ca learn-troubleshooting documentation.

 

[wehey]

Does the voltage drop during the acceleration? By how much, if so?

If it's enough of a voltage drop, the controller could hit LVC and shutdown, then the voltage will bounce back, which is the voltage you'll then read if you only check after the event. THis is probably not the issue since it works on hills, which would have voltage sag under load similar to acceleration from a stop.



For the hall error, you can check first the connections, and cables. If you find no mechanical problem to fix, then you can perform the hall test per the ebikes.ca learn-troubleshooting documentation.

Thanks for the reply!
The voltage is only dropping by 1.5-2v under load. Also I did check the power meter which captures min battery voltage. The lowest it reached was 46v during this ride and I started out on 50v. I am pretty sure the battery is ok despite it being 4 years old now.

I will do all the other tests today and report back.

 

[wehey]

So I have had a little tinkle.
The halls all check out fine and return 4.6v each. This is really odd as the controller thinks the issue is with the halls (8 flashes)
I took it out for another ride and it’s still doing the same thing but worse. It’s actually cutting out at slow speeds on hills if I use more than a tiny bit of throttle.

I have a plan moving forwards…. I have a lot of Ezee spare parts. A front hub motor and a 20A controller.

First thing I’m going to do is fully charge the battery. It hasn’t had a full charge in about 8 months, so maybe there’s a cell thats out of balance.
Next will be to install the front motor which I know is in good working order. If this motor cuts out then I know it’s the battery (or poss the controller) if it doesn’t cut out then the problem lies with the rear motor.

let’s see eh

 

[amberwolf]

The halls all check out fine and return 4.6v each.

How exactly did you run the test, step by step? This will help us help you figure out why you have an incorrect or invalid test result (or if the halls are actually bad).

Just so you know, the typical motor halls (bipolar latching, open-collector output) don't output any voltage. They only ground whatever voltage is placed on their outputs by the controller's built-in pullups, whenever they are activated by magnets.

So if you are not reading the changes in the halls as the motor spins, the halls are not working, you are only reading the voltage placed on their outputs by the controller pullups.

If it is not connected to the controller during the test, then you must provide your own pullup voltage via resistor to each signal line as well as 5v to run the halls, so you can see if the halls are switching correctly as the rotor turns and magnets pass them.

 

[wehey]

How exactly did you run the test, step by step? This will help us help you figure out why you have an incorrect or invalid test result (or if the halls are actually bad).

Just so you know, the typical motor halls (bipolar latching, open-collector output) don't output any voltage. They only ground whatever voltage is placed on their outputs by the controller's built-in pullups, whenever they are activated by magnets.

So if you are not reading the changes in the halls as the motor spins, the halls are not working, you are only reading the voltage placed on their outputs by the controller pullups.

If it is not connected to the controller during the test, then you must provide your own pullup voltage via resistor to each signal line as well as 5v to run the halls, so you can see if the halls are switching correctly as the rotor turns and magnets pass them.

I did the test exactly as per this article https://ebikes.ca/documents/HallSensorTestingFinal.pdf
All of the halls were switching between 0v and 4.6v as I rotated the wheel

 

[wehey]

So I have come to the conclusion that it’s the motor that’s causing the issues.
I wired up my old Ezee front motor to the same battery, controller and throttle and it works flawlessly.
Wired the dodgy rear motor back in and the same issues returned.
Its also noticeably noisier and grumbles under load.

 

[amberwolf]

I did the test exactly as per this article https://ebikes.ca/documents/HallSensorTestingFinal.pdf
All of the halls were switching between 0v and 4.6v as I rotated the wheel

Ah, that is different than your original test results report (which just said that you got 4.6v, which implied they are not working or the test was done differently than necessary).

If they're switching correctly, then the halls are working, at least for basic function. There could still be electrical noise from connection problems (anywhere between the sensors and the controller, usually at the connector itself), or from noise induced in them from phase wire currents.

Do your Ezee's use the JST connector (like the ebikes.ca pdf shows)? If so, it's easy for pins to back out of the connector when plugged in, and cause a poor connection, but look like they're good when unplugged. (that's why some of them are filled with hotglue or silicone from the back). It's also possible for there to be a spread or bent contact that looks ok visually but is just enough to cause connection problems and signal degradation. Or a crimp problem between the wire and the contact, or even a broken wire at the exit of the contact, so it makes a connection, but a poor one that works less well than it should.

 

[motomech]

Hiya all.
Just after your opinion on this issue I have.
I have a rear Ezee motor, Ezee 25Amp controller and 48v battery.
The motor cuts out when I pull away giving it full throttle. The wheel starts to turn then after about 0.5 to 1 revolution it stops. There is still voltage at the inline power meter so I don’t think it’s the battery.
I have checked the Ezee controller and it flashes 8 times which means a hall sensor fault.
The rest of the time it rides just fine, climbs hills like a beast, and as long as I accelerate off the line gently it works faultlessly.
So is it likely to be a hall sensor in the motor at fault or could a dodgy hall sensor wire/connector cause this.
Thanks in advance.

I went though this years ago when Grin sold me several defective used motors
It was a common problem that the Hall wires were too short in their run to the PCB. It started out as an intermitent issue as viberation or rotational forces would cause the solder joints to lose contact ad eventually they would septerate entirely from the PCB and the motor wouldn't work at all.
To fix, you will need the up-dated PCB (W/ bigger holes) and Halls from Grin. Then the wires will need be lenghtened. It's futzy work, but can be done.

 

[amberwolf]

That's an interesting defect / failure mode...Iv'e seen it with other things (especially inside controllers) but not yet with the hall boards. I'll have to keep that in mind for future posts asking about similar Ezee failures.