9c phase wire replacement...help

[johnrobholmes]

When you move the wheel a bit, does the green/ blue hall change readings at all? That is the culprit if so.


Sounds like you were using the meter right. That is how pretty much all meters work.

 

[itchynackers]

No, the Green/Blue reads zero all the time no matter what. Should that one oscillate to 4.97V also? If so, I'll begin to tear the motor down again. I'm just not sure how in the world I'll get a small wire through that axle now. It's jam packed already.

 

[johnrobholmes]

Yep, that is a hall output. The red is your positive power, should be around 5v from black to red at all times. The hall outputs will fluctuate from 0 to 5v when tested from black to the hall output.

 

[RallySTX]

Just watching with fingers crossed here Itchy. As usual JRH to the rescue!
Brian L.

 

[itchynackers]

Just have to find the time..........and the motivation to do a tear down again. I get depressed just thinking about it.

 

[itchynackers]

Ok...after lots of swearing, I found the problem. The blue hall wire was severed inside the axle. Completely cut apart. I must have cut it while pulling the 3rd phase wire through. Finally was able to wire everything back up. Doesn't look as pretty (since I had to cut the shrink wrap off) but it works. Any novice (like me) thinking of doing this, better think hard. If you have any doubts, or don't have that "never say die" mentality, or are one of those people who thinks its ok to lose sometimes, then do not attempt this mod.

Now,....what upgrade to do next, hmm...

 

[John in CR]

"...while pulling the 3rd phase wire through"...There's your problem. The entire wiring harness needs to go through at once, and it should be enclosed in a protective sheath.

I finally got around to mine today. I used magnet wire, 17 strands of 24ga per phase, so a bit larger than 12ga. I also included an extra pair for adding a temp sensor later. I only twisted only the ends together of each 17 strand group, so the phases are separated at the ends. Then I wrapped the entire bundle of 53 strands of magnet wire plus the 5 hall sensor wires in a single layer of electrical tape, and covered that in shrink wrap. I didn't have enough shrink wrap and didn't fully trust it as a single layer, so right or wrong I used that layer of electrical tape.

I staggered the phase wire ends so the end of my bundle was tapered. I also bent them before feeding into the axle, and the whole thing went through quite easily and I didn't use any lubrication. Both of these were intended to make getting the bundle through the 90° bend easier. It worked quite well, since I was just testing before deciding on a lubricant and it came through easy enough to forgo it.

My 9C is 9 strands by 7 turns of what appears to be 24ga, so even my 17 strand phase wires is overkill IMHO for that short run out of the axle. OTOH the 16ga (maybe smaller) phase wires the motor came with are totally unacceptable.

John

 

[itchynackers]

I understand your method. But, I didn't have room for a single layer of shrink around the bundle. There simply wasn't enough room. I'm not sure if the teflon wire I was using had a thicker insulation layer or what. It looked thin enough.

 

[John in CR]

I understand your method. But, I didn't have room for a single layer of shrink around the bundle. There simply wasn't enough room. I'm not sure if the teflon wire I was using had a thicker insulation layer or what. It looked thin enough.

If you pushed a 3rd phase wire through as loose wires, then I think a shrink wrapped bundle should have been even easier. Those 9C hall wires a kinda big compared to other motors I've seen, so getting them in the gaps between the phase wires would be a space saving advantage as would holding the phase wires straight and true and probably deforming them from round too like a good shrink is likely to do.

From now on I'm sticking with the magnet wire approach. Then I can tailor my harness exactly to the available space, and not waste space with extra dielectric, twisted wires, and dead space between 3 phase wires with a circular cross section going into a round hole.

My only time consuming part was scraping the enamel off the ends of the magnet wire. Next time I'll just try solder to get it off.

John

 

[RallySTX]

Horrayy! Good Job man!
Brian L.

 

[itchynackers]

Thanks Brian. I'm bored now. Can't ride the bike because of the snow/ice. I've completed changing over to 12awg teflon and silicone wires with 4mm bullets throughout. I NEEEED another mod to work on. I'm contemplating the air cooling mod, but probably should wait until I can verify that motor heating is actually a problem. Same goes with the controller. If I get significant heating, I may put a small fan in the controller case. But again, if I don't need to do it, then I don't want to expose the internals of the motor/controller to the elements. What else can I do? Ahhhh!

 

[RallySTX]

Oh I would definitely make sure heating was an issue before putting holes in anything. You know how fast the weather can change arround here. Now if you had the controller in a bag or box, I could see stuffing a CPU fan directed at the hot spot inside there and adding some vent slots for exhaust. Kinda hard to offer much more info without seeing the bike layout.
Get that controller into the air stream as much as possible and be sure to weather proof te connections. Sand the outer covers on the motor til they are thin and then polish them and add a layer of clear coat wax or polyeurathane for max heat transfer. Make sure all connectors and wires on bike remain cool after extended run or beef them up as heat denotes resistance and ineffeciency. I feel you about the snow, I'm kinda reluctant to walk the Memorial bridge now. Stay warm.
Brian L.

 

[Spacey]

Just starting my journey on the 'replace your phase wires on 9C', your thread has helped me a lot though so thanks for posting it up.

 

[dnmun]

for the phase wires, 12G will work (i guess the teflon insulation is the thinnest), with the 5 sensor wires inserted in the middle of the 3 wires in a bundle. you won't be able to get it through if you have heat shrink on it and you don't need heat shrink. taper the ends of the phase wires so the edges can't hook on the inside of the axle.

the biggest problem, so hard you will end restarting several times, is to keep all the wires aligned coaxially as you push it through the axle. i wrapped the wire bundle with thin stiff cardboard to hold them together and get traction to push, but they will try to kink on you as soon as you hit a small ding on the inside of the axle. try to be patient then so you don't bend the wires a lot while pushing, and get a small pick so when the wires appear at the opening on the inside, you can reach into the hole and catch the end of the wire and bend it towards the opening, a little at a time, for each wire. the biggest problem is how the sensor wires ride up to the outside of the bundle and then tear on the inside of the axle and short to the axle itself, which means you have to pull it apart and start over, so work carefully to avoid that.