Shenzhen (ecrazyman) Controller Information

[John in CR]

OddJones,

Did you try riding the bike with the "reverse nudge" to get going? If not, give it a try, and if it does run fine other than the start, then it's not the motor and you just fried something in the controller with your bad wiring combo torture test for hundreds of yards including a hill attempt. Until you do that, I don't think you can rule out the controller or damage to the motor with that first run, since it was dumping loads of current through the motor essentially fighting against itself due to an incorrect "firing" order.

If it doesn't run well, then take your choice on which one to open up first to look for trouble.

John

[fechter]

When testing the hall sensors you need to turn the wheel backward so the rotor moves.

[gip_mad]

John, if you watch the videos you can clearly see that he has an interrupted phase wire.

The hall sensors purpose is just that: provide synch to start the motor even if it is stopped. If you measure the hall voltages with the motor stopped, you will see that they are not all the same: that is to tell the controller wich phase to energize first.

[John in CR]

John, if you watch the videos you can clearly see that he has an interrupted phase wire.

The hall sensors purpose is just that: provide synch to start the motor even if it is stopped. If you measure the hall voltages with the motor stopped, you will see that they are not all the same: that is to tell the controller wich phase to energize first.

I only watched the first one before. Will a motor spin up that well on just 2 phases? I guess his "ugly sound" that ended the initial bad test ride was the pop of a winding. The problem now is that the test ride may have destroyed any evidence if the motor was faulty to begin with. Time to open it up and see what things look like. I hope it was just a bad solder connection on a phase wire that finally popped loose and is easily repairable, and that the controller survived. Then he could be on the road in a jiffy....optimistic but possible.

John

[gip_mad]

The motor would spin without a phase, but it would be noisy and very inefficient, and almost unable to move under load. You shouldn't burn mosfets if you have an interrupted phase.

[oddjones]

bad wiring combo torture test

Heh heh - that's me, gonna have it put on a t-shirt

[oddjones]

The motor would spin without a phase, but it would be noisy and very inefficient, and almost unable to move under load. You shouldn't burn mosfets if you have an interrupted phase.

It doesn't sound noisy to me?

[gip_mad]

The motor would spin without a phase, but it would be noisy and very inefficient, and almost unable to move under load. You shouldn't burn mosfets if you have an interrupted phase.

It doesn't sound noisy to me?

On the spinning video... It should be almost silent. Or is it the auto gain adjustment on the microphone that amplify it too much?

[John in CR]

The motor would spin without a phase, but it would be noisy and very inefficient, and almost unable to move under load. You shouldn't burn mosfets if you have an interrupted phase.

It doesn't sound noisy to me?

It definitely sounds rough at lower speeds as it's accelerating. Like gip_mad said, that resistance of 1 between 2 of the phase wires tells you something is wrong with it. Another way to tell is with nothing connected, spin the wheel against the motor resistance. Then short 2 of the phase wires together and try again. It should be significantly harder to turn due to the electronic braking. Then short the other phase too. If doesn't get more difficult to turn, you've got a problem.

John

[fechter]

Another way to tell is with nothing connected, spin the wheel against the motor resistance. Then short 2 of the phase wires together and try again. It should be significantly harder to turn due to the electronic braking. Then short the other phase too. If doesn't get more difficult to turn, you've got a problem.

John

That is the best test. Measuring resistance (ohms) will only tell you if a wire broke off and is disconnected unless you have a really fancy meter.

If a winding or wire shorts, the turning resistance will always be present and not increase much when you short a certain combination of phase wires during testing.

[gip_mad]

Measuring resistance (ohms) will only tell you if a wire broke off and is disconnected

Exactly, it is disconnected....

[oddjones]

Another way to tell is with nothing connected, spin the wheel against the motor resistance. Then short 2 of the phase wires together and try again. It should be significantly harder to turn due to the electronic braking. Then short the other phase too. If doesn't get more difficult to turn, you've got a problem.

John

oh dear.

Yellow - Blue = +resistance
Blue - Green = nothing
Green - Yellow = nothing

I guess I just have to pull the motor to pieces and hope that green wire's hanging off?

Houston?

[docnjoj]

Knuckles will save U!!!!!!! But yeah! U will have to open the motor!
otherDoc

[oddjones]

Knuckles will save U!!!!!!! But yeah! U will have to open the motor!
otherDoc

Surely it can't be this simple?



Gonna solder it up now... so excited!

[docnjoj]

Cant see from the photo but sometimes U bite the bear! Did u find the offending phase wires?
otherDoc

[oddjones]

>>risks a wan smile<<

Yeah - sorry, crummy photo - the bit highlighted is the green phase wire completely separated from the winding.

well... soldered up the green phase wire, and everything seems better - all phase connections now stop the wheel spinning backwards when shorted. Resistance across all phase wires now an equal 0.14 on my meter.

Gonna leave it for tonight - get me some more fuses(!) in the morning and run the tests again...

Guys - thanks for all your help - I feel like I might be on the home straight - couldn't have done it without your help!

[Tiberius]

Hi Oddjones,

Just reading back a bit and noticed you're in the UK. Whereabouts - I'm in Somerset?

I have two Bafang motors and one has just developed an intermittent Hall signal. If we have to get parts shipped maybe we can join up.
Ok, just crossed with your last post. Well done, sounds like you won't be needing that expensive shipping.

Nick

[oddjones]

Hi Oddjones,

Just reading back a bit and noticed you're in the UK. Whereabouts - I'm in Somerset?

I have two Bafang motors and one has just developed an intermittent Hall signal. If we have to get parts shipped maybe we can join up.
Ok, just crossed with your last post. Well done, sounds like you won't be needing that expensive shipping.

Nick

Sunny Liverpool mate, home of 50ft mechanical spiders - it's early days yet I guess - I may well need to take up your offer if the tests crap out again tomorrow - if there's one thing I've learned through this whole process it's check check and check again before you wire the thing up and I've had a couple of celebratory beers since I fixed the phase wire so I'm leaving it til the morning!

[docnjoj]

If my Halls go bad I'm gonna try that BEMF sensor board from Knuckles. No hassles and lose the Halls and their little teeny wires!
otherDoc

[gip_mad]

Wait oddjones! Now that you discovered the problem, how do you repair it? I hope you did a good job, but here are some suggestions:
If you are soldering for the first times, DON'T DO IT! Soldering seems easy, but there are a lot of variables that you can only learn in years of practice. A good solder job on that wire is FUNDAMENTAL. Don't reuse the old lead, put a good amount of new one and be sure that everyfing melts uniformly. Bad solder joints may break easily, and this time you may be not as luky as the before, and have the floating wire short with something.
Also, good isolation is a must. You should use shrinking tube to cover the exposed connections.
Next, remember to clean your job and make sure that pieces cannot fly away and get into the motor while spinning.

I hope that you can get your bike running very soon!

[oddjones]

Ah! that's more like it! - and the motor IS quiet!

(phase wire soldered, crimped and sheathed gip_mad, you'll be glad to know)

OK - so redid all the tests, came up with a setting which really seemed to work well - smooth, quiet, powerful, low current drain - all good.

Took it out for a run and it was completely different from first time - a pleasure to ride. Took it for about a mile and it was comfortably pulling me up hills and around my local park no problems.

On my way back home I took it up the steepest hill round here and it cut out - the lights went off on the throttle and I lost all power - if I flicked the power switch (between battery and controller) off and on I got power back but as soon as I put it under any load I lost power again....

I'm hoping this is a low voltage cut-out issue - (I have actually never charged my battery - I had a whole separate wiring issue with that which you guys have thankfully been spared!) - so I spent the afternoon finally figuring that one out and the battery is now quietly charging ready for another test tomorrow

[oddjones]

If my Halls go bad I'm gonna try that BEMF sensor board from Knuckles. No hassles and lose the Halls and their little teeny wires!
otherDoc

Link it up! - just tried a search on "BEMF sensor board" - but got nothing...

[gip_mad]

I'm glad you had it working! The LVC behavior is strange, but maybe your batteries are so dead thet you have to let them recover a bit... Never discharge them so much!

[docnjoj]

If my Halls go bad I'm gonna try that BEMF sensor board from Knuckles. No hassles and lose the Halls and their little teeny wires!
otherDoc

Link it up! - just tried a search on "BEMF sensor board" - but got nothing...

Try this and PM Knuckles!

otherDoc
viewtopic.php?f=2&t=4464&p=94155#p94155

[oddjones]

OK - the battery took a good 4 hours of charge which tells me it was pretty kippered. After that it took me up hills no problems...

My fit-as-a-fiddle 16 year old road-biking son took it out and came back "impressed" - which is praise indeed. Am taking it to work tomorrow - which'll be the big test. By my cheapo cycle computer I reckon I'm doing about 18mph which is actually fairly OK - but it does lead me on to the next, inevitable question...

How do I make it go quicker?! I don't want to be screaming along - but I reckon about 25-30mph will do me grand for keeping up with traffic - is this something I can reasonably expect from my 36v 10ah battery (I only need a range of 5 miles as I can charge it up at work when I arrive) or do I need to get saving for a 48v battery?

Don't get me wrong - I'm hooked, it's just an inevitable part of my character to take anything and want to make it faster