Error 09 - motor phase fault

[Hcm]

Hi guys, any guesses why this error appears?
Just installed it, bafang 500W 48V rear hub with dpc 18 display.

The seller says it should be the extension cable, I checked it and reconnected it but the problem continues... He keeps insisting it is the extension cable but doesn't seem likely... :|

Only happens at high power (>700W) and the motor keeps working nonetheless... Disappears once the power drops closer to 500-600W

 

[ThierryGTLTS]

It's not completely stupid, if there is a small imbalance in the wire resistance.

700W require a fairly high current in the motor phase cables, thus a small resistance difference can create a voltage drop.

And the controller consider that as an motor phase fault.

So it may be interesting to try with no cable extension or another cable.

Have a Nice Day.

Thierry

 

[Hcm]

@ThierryGTLTS
Thank you for the input!!
Can't try without the cable, the controller cable is too short.
I will try to measure the resistance in the phase wires and ask for another extension cable.

 

[amberwolf]

It could simply be there's too much inductance or resistance, or even capacitance, when using the extension cable.

That could be caused by the connectors, rather than the wires; if that's the case, then if the cables were directly spliced together, it would probably be ok.

But it could be a combination of all of the things together.


The only ways to test are to eliminate things by experiment, and the best way is first to move the controller to where it can reach the motor wihtout the extension cable, at least for a quick test.

 

[Hcm]

It could simply be there's too much inductance or resistance, or even capacitance, when using the extension cable.

That could be caused by the connectors, rather than the wires; if that's the case, then if the cables were directly spliced together, it would probably be ok.

But it could be a combination of all of the things together.


The only ways to test are to eliminate things by experiment, and the best way is first to move the controller to where it can reach the motor wihtout the extension cable, at least for a quick test.

Thank you for the help!

Regarding the connection of the wires directly, I would rather keep the waterproof quick snap connectors... This is supposed to be a plug and play kit! But will keep this option as a last recorse...

Not sure how but as you guys say, I will try to test with the controller connected directly to the motor.

 

[amberwolf]

It should be possible to make it work with the extension, but it depends on the design of the system, and why exactly it's not working. If it's a bad extension cable, that's an easy fix. If it's a capacitance or resistance or inductance issue, it's a little tougher.

If it doesn't work even without the extension, then it just means you have a "normal" problem of bad connections, wires, or motor/controller failure.

 

[Hcm]

So, managed to securr the controller in the triangle bars with some velcro and connect it directly to the motor but the problem persists...

Anyway, the seller is sending a new extension cable and I think is asking me to choose a new display. Any difference between the 850C and the 18C (the one I currently have) ?

 

[amberwolf]

So, managed to securr the controller in the triangle bars with some velcro and connect it directly to the motor but the problem persists...

Then that means it's not the extension cable.

It could be a connector problem, a wire problem, some setting in the controller not compatible with the motor, or an actual motor or controller defect. :/

 

[Hcm]

So, managed to securr the controller in the triangle bars with some velcro and connect it directly to the motor but the problem persists...

Then that means it's not the extension cable.

It could be a connector problem, a wire problem, some setting in the controller not compatible with the motor, or an actual motor or controller defect. :/

That's what I was thinking and asked about the problem being with the motor or controller but the seller insists on sending a new display...

Any chance he can just disable error checking to seem like there is no error with the new display? (I chose the 750C display)