Help with electrics please

[AndyOfTheSouth]

Thanks. Will do then report back.

 

[torrent99]

Ok Andy,

You've got three general classes of problem to check for:

Fault in the motor. Generally this doesn't leave it completely dead; it will twitch or run roughly. Try turning it backwards to see what happens.

Fault in the controller. Not much you can do to about this; it either goes or doesn't go. But it should generate 5 V or 12 V to run the throttle and the Hall sensors and you can check that with a meter. You can also check the throttle signal with a meter. It should vary over 1 V to 4 V as you turn the throttle

Connection/configuration problem. This includes all the extra wires going into the controller. My guess is that some of them have to have the right connections to enable the controller.

Nick

OK I'll have a stab in the dark....

Another thing to check (which has already been mentioned) is the brake switch leads.

Your controller looks like mine (though I suspect they're all similar), and on that these are the blue & black wires with the black connectors on the end. In your photo these look like they are the ones in the very bottom right.

Their action is is they are short circuited (i.e. the brakes are pulled) then the motor stops.

Of the remaining "unused wires" it's very hard to tell!
a) The two blue wires with lots of connectors in between is particularly confusing. AHHHH!!! I think that's the speed restrict circuitry. Make sure it isn't short circuited or that might result in restricting it to 0mph.. of course it could work the other way around so that it needs to be short circuited for full power.
b) As is the orange wire that's a real mystery. EDIT... I seem to remember some controllers have an enable/disable wire, if my other guesses are correct this would be it. However, I'd expect it'd be wired in such a way that if you left it floating everything would still work.
c) The top black "unknown" wire with the square connector block I'm guessing is the attachment for the pedelec sensor?


BTW Just to explain the lights you are seeing. That lead from the battery to the throttle is not in fact to the throttle itself. It's just to the lights which show the state of the battery. Hence you can get lights (battery switched on), but nobody home.

 

[AndyOfTheSouth]

Thanks for joining in, Torrent.
Nick - wheel runs OK backwards. No sure how to do those voltage measurements.

Have attached photo of connected motor. Have tried with and without the two unattached blue wires connected together. Have tried with and without the brake wires connected (though in this case it seems clear that they should be open circuit for it to work.)

Don't know how to do anything else to enable. It is very tantalising, as though small thing is missing...

 

[torrent99]

Thanks for joining in, Torrent.
Nick - wheel runs OK backwards. No sure how to do those voltage measurements.

Have attached photo of connected motor. Have tried with and without the two unattached blue wires connected together. Have tried with and without the brake wires connected (though in this case it seems clear that they should be open circuit for it to work.)

Don't know how to do anything else to enable. It is very tantalising, as though small thing is missing...

Now THAT looks even more like the controller in my '07 Wisper! If it is the same you want to leave the blue wires open circuit (i.e. don't connect them together). The brake cutoffs also need to be open circuit. The orange wire you can ignore.

YOU GOT IT TO RUN BACKWARDS!?!?!?!

That's brilliant! It means you have something working....although hold on....HOW? The tongxins have a freewheel don't they? So how could it go backwards???

Anyway assuming it *can* go backwards, all you have to do now is get the wiring order sorted out of the 3 motor wires. You just play with the combinations until it goes forwards in the smoothest way!

 

[AndyOfTheSouth]

Alas, your enthusiasm, welcome though it is, isn't warranted.

I meant that it will turn backwards. At this stage, if I could get it to run backwards I'd regard that as sufficient and I would adapt my riding style accordingly... sigh...

 

[torrent99]

Thanks for joining in, Torrent.
Nick - wheel runs OK backwards. No sure how to do those voltage measurements.

For the throttle:

Switch your meter to DC say 20V range. Connect probes to the throttle wires in pairs Red & green, red & blue etc...see what it says. Try turning the throttle. (don't worry about negative readings)...

For the 3 motor wires:

Switch the meter to AC say 40V or above range. Twist the throttle & see what happens.

However, and I mean this with great respect, if you're not sure of how to use the multimeter perhaps you should leave it to the shop to fix?

Another thing....you DO have the motor mounted in some sort of forks yes? Coz if you don't and you manage to get the motor to work it'll spin the motor cable until the wires break inside. And then you'll really be in trouble!!!

 

[AndyOfTheSouth]

Well, bit of excitement. I measured the throttle pairs
yellow/black, 0.17
black/red, 0.41
green/red, 0.22

there was no change when the throttle was twisted

Then, I started on the other pairs
red/blue, 0.88
black, green, 0.91
black, red, 0.02
black, yellow, 0.91

at some point in this process, the motor started!!!!!
I was so excited, I stopped what I was doing and tried to connect it all up again. When I tried again, it was dead once more, except for the light.

Does this mean connection problem or controller problem?

I will go to Oxford tomorrow if I can. If you have any ideas of what is wrong, I'd still be interested and grateful.

Thanks

Andy

 

[torrent99]

Well, bit of excitement. I measured the throttle pairs
yellow/black, 0.17
black/red, 0.41
green/red, 0.22

there was no change when the throttle was twisted

Then, I started on the other pairs
red/blue, 0.88
black, green, 0.91
black, red, 0.02
black, yellow, 0.91

at some point in this process, the motor started!!!!!
I was so excited, I stopped what I was doing and tried to connect it all up again. When I tried again, it was dead once more, except for the light.

Does this mean connection problem or controller problem?

I will go to Oxford tomorrow if I can. If you have any ideas of what is wrong, I'd still be interested and grateful.

Thanks

Andy

0.41 etc !?! That seems very low. In fact not really registering at all.

What scale did you have the meter on?

Good news that the motor started. It means that it might work at some point.

On the throttle I'd expect:
black/red = 5V (or 12V)
black/(green or yellow) = 1V to 4V depending on the throttle position.
(that's of course if the colour coding follows my "common electrical sense")

I'd say that on balance you have a connection problem...can't say where though.

 

[Tiberius]

Several things puzzle me here.
First, as Steve says, those voltage readings don't make sense, unless the meter is on the wrong range, or the controller is in some kind of shut down mode.
Secondly, when you say the motor started, what was the throttle set to?

Nick

 

[AndyOfTheSouth]

Hi Nick and Steve

The range, so far as I understand it, was as Steve suggested, though given my degree of familiarity with ammeters, I can't swear by it.

The sudden start happened as I prodded some of the cables with the ammeter probes and turned the throttle. Alas, I was so surprised and indeed ecstatic, I leapt about and was keen to try and see if it worked on the bike. Which it didn't.

At which point I lost heart and resolved to take the wretched thing back to the shop in Oxford, which I expect to do tomorrow.

Sorry for being an unworthy pupil, but I will let you know if TETS say anything interesting.

Thanks again

Andy

 

[Fecn]

You should have been using a voltmeter for testing rather than an ammeter - That explains all the low readings.

An ammeter is essentially a short circuit, so somwehere in your testing, you found that connecting two wires together made the motor run... the trick is finding out which two wires it was and doing it again.

 

[AndyOfTheSouth]

I think, though naturally I stand to be corrected on this, I was using a device which could be either and I switched it to the voltmeter setting as per the instructions. I was using 'ammeter' as a general term for that sort of device...

 

[rog_london]

You should have been using a voltmeter for testing rather than an ammeter - That explains all the low readings.

An ammeter is essentially a short circuit, so somwehere in your testing, you found that connecting two wires together made the motor run... the trick is finding out which two wires it was and doing it again.

I've been following this one with some horror - I don't think I have anything to say which might get Andy where he wants to go - indeed, the most sensible idea I've seen so far is his decision to go back to his supplier.

If engineering were that simple, and the results of an ill-informed mistake couldn't be so expensive or risky, there wouldn't be any need for dealers' mechanics and electrical experts.

Anybody can be taught, but not electrics/electronics from scratch through a forum. Some basics are absolutely necessary.

Rog.

 

[AndyOfTheSouth]

Don't worry too much, Rog. My incompetence is purely superficial and conceals what is merely an underlying lack of understanding.

 

[rog_london]

Don't worry too much, Rog. My incompetence is purely superficial and conceals what is merely an underlying lack of understanding.

Nothing personal, mate. I didn't mean to imply that you were stupid, just that if you don't understand it can be expensive.

Rog.

 

[AndyOfTheSouth]

Don't worry, that's fine, I wasn't offended . Actually, if I think about it logically, the supplier jolly well should sort it out, since I paid for the kit to be installed! I just wanted it to be working...

Actually, I like being in Oxford, so I will make the most of it.

 

[Fecn]

I think, though naturally I stand to be corrected on this, I was using a device which could be either and I switched it to the voltmeter setting as per the instructions. I was using 'ammeter' as a general term for that sort of device...

My apologies for the potentially very bad advice - to me with my electronics background ammeter only meant something that measured Amps and it never occurred to me that you might have meant otherwise. If you had been measuring amps, then what I said would have been fine as you'd already done it once and got the motor working as a result, but if you weren't measuring amps before, it would probably have blown fuses/controller etc. As a general rule it is a really bad idea to short-circuit things at random unless you want to see the magic smoke escape.

As rog says, electronics from scratch via forum is not the way to go. As you say, supplier should jolly well sort it out.

 

[frank9755]

I've come to this one late and agree that your best bet is to put it back to ETS.
I note your controller looks like an eCrazyman one, not Tongxin's own. I've used both and had both blow - which I think it most likely. With my first one, John on this forum kindly did a test for me and found that the controller would work if spun backwards first. I suspect that is what has happened to yours - the controller has blown and is therfore useless to you, but some of the circuits will work under specific circumstances.
Controllers are not expensive - if you buy them in bulk from China they are <£10 each, so I would have thought ETS would just swap it out.

 

[AndyOfTheSouth]

Hi from Oxford. Have dropped off the bike and kit. Was hoping to pick it up this afternoon, but just had phone call from them asking for the key!

I am less bothered by this than might be expected since I'd prefer it to go back to Cambridge to their workshop and be properly sorted out. Their Oxford shop is one man in a limited workshop doing it when he has time. They have a workshop day in Cambridge (Tuesday) when they can be more comprehensive. (I have discovered these things over the course of the past few weeks. Hey ho.)

By the way, I am very grateful for the advice I have received. I disagree with the view that this forum is not for tutorials. If not here, where? It is the ideal channel. When I started, I knew nothing about electric bikes. Now I even own my own ammeter! Or should that be voltmeter? Damn!

 

[Tiberius]

I am reminded of two different conversations I had some years ago with work colleagues when new technology came along.

A: "Is there a course the management can send me on?"

B: "We have no knowledge or experience of this. That's never stopped us before; let's get stuck in."

Nick