Idea for shorted out hub motors.

[zibbby]

Hi!

I see quite often the hub motor get shorted out due to wet condition like rain and probably condensation.
Seems like sealing does not work , it is better if breath .
What about if you drill hole on each side about 1” diameter and have instell removable rubber plug. So after driving in wet you would just open two holes and let it dry overnight. If there was also installed SS mesh behind that hole it could be use in dry weather and get better cooling for the windings, and will not let the debris go in.
What do you think?

 

[fechter]

That might work.

If the hall sensor wires are sealed where they enter the actual hall sensors, the rest of the motor should be very water resistant. Rust is more of a problem.

A vent will allow any trapped moisture to escape. The vent does not need to be very big. I'd say a 1/2" hole should do. It should be located close to the outside diameter so any pooled up water could run out when the hole is pointing down.

 

[John in CR]

The real answer is to build hub motors to better standards to be essentially immersible, and while they're at it, the connection to the frame needs to be properly engineered. They're used for transportation, and I haven't seen any "for use only in dry conditions" in any promotional literature. Both waterproofing and securing to the bike properly have relatively easy solutions, and we as customers should accept nothing less.

That's my $.02 anyway.

John

 

[mvadventure]

Since I'm in the middle of trying to replace a shorted out motor I agree with John. The first time this happened, more than a year ago, the bike sat for four or five hours under cover and worked great afterwards except for the right brake handle no longer disengaged the cruise control. This time the rain took the motor and controller and it looks like $750.00 from EV depot to get back on the road.

But, and this is a big but: After the first time a lot of the responses I received dealt with applying silicone to the throttle, cruise control, controller and wires leading into the motor at the torque arm. This I did and since I'd had no problems since (maybe because I hadn't been caught in anything but a light shower) I thought the system would work. I covered the throttle and cruise with plastic bags when it started raining and the controller was already in one. The water entered, apparently, where the wire exists the center next to the axle. This was an area I figured the factory would certainly protect from intrusion. Wrongomundo. There was no sealant of any kind and in reality that area allows dust and grit to enter.

Oh well.
Mike

 

[I AM 0Z]

I don't know how well sealed my motor is but, being a machinist I was able to install flat "O" ring gaskets in the face plates and blocked the cable whole with silicon and i sprayed the whole thing with WD-40 as it does not conduct and will displace water (a little trick i picked up from my days when cars had breaker points in the distributor)before i closed it up. Now i really have no idea how well this is working but I do know my hall effect sensors are still functioning quite well because I have tested them with a 9 volt battery doing routine scheduled maintenance. I am sure that one day it will be necessary to open it and I'll find out then and until then if it isn't broke I am not gonna fix it.

 

[John in CR]

I too decided not to wait for the manufacturers. After my axle spun, I needed to rewire and went to the heaviest gauge phase wires I could fit. Then I used 700°F silicone from the auto parts store to hold all wires in place inside the hub and make a good seal with it where the wires exit the axle on the inside. On the outside I made a drip loop with my cables that I sheathed in an extra covering of clear plastic tubing. I keep the axles well greased where they enter the bearings. The only thing I thought of doing, but didn't since silicone releases acetic acid as it cures, was to run a bead around the covers before closing it up. BTW I did leave the motor open for 48hrs after the initial silicone treatment.

Knock on wood, but I put about 50 miles of Pacific beach riding in last week during low tides without incident, other than the result of my damaged Ping pack and a bit of corrosion on my unpainted Frankenstein dropout prosthetic replacements (increased axle diameter to almost 1" using sleeves threaded inside and out, plus 1/2" steel as the dropout welded to slit tubing that slides right over my front shocks, so I never have to worry about an axle spinning again). I did carry it over the few small rivers that were deeper than the axle, but otherwise sand and salt water got everywhere, including through some of the initial layers of tape protecting where the wires enter my Knuckles controller. If you're confident of your waterproofing and have a high speed ebike, I highly recommend deserted beach riding during low tide....no cars and dead smooth if you watch out for rocks and shells. My daughter and I had an absolute blast rocketing right along the ocean at 50kph.

Eventually I'll protect the batts and controller enough to ride with confidence through rain and water, though I'm a bit unclear of the risk areas in a hall throttle. Gotta get rid of this twist grip before tackling the throttle anyway. E-bikes have to be all weather before introducing them to the masses, so we're the pioneers. Maybe the Chinese are just sending us the substandard stuff, because I don't understand how they put almost 20 million electric 2 wheelers on the road each of the last 3 years if they all crap out from a bit of water.

John

 

[mvadventure]

I Am Oz: Could you go into detail on how you tested your hall sensors? I read what Fechter has posted in a much earlier thread and tried following his directions but had quite a bit of trouble figuring them out. I think mine are fried but since my actual understanding of ther process is limited (very) I would be much more confident in the need fopr replacing my motor if I knew for sure.

I've ordered a new motor and controller and it's been suggested I simply wait 'till everything gets here and hook up the controller and then try it with the old motor which would be simple enough except I've also heard that a shorted motor would blow a controller instantly. Since my controller stayed dry during the recent drowning episode I do know something shorted it out and it had to be the motor. In the meantime I wait on EV Depot.

Mike

 

[I AM 0Z]

OK Mike:

Since my controller drowned and in my email conversations with flechter he mentioned hall sensor being in good shape and as i read it i'm thinking to myself "damn i am a machinist, what the hell do i know about a hall sensor whatever that is?!!!" and then i remember my Father telling time and time again when all else fails read the instructions. So here i go reading up on hall sensor testing. So, i go thru my junk and i find a gadget that is no longer working but ran on a 9 volt battery and out comes the battery hook up it had. Now, seeing as how i have what appears to be a milk crate box on the back of my bike, i can tip bike bike upright and it comes to rest on the box corners and the rear wheel (I could have taken the time to build a stand for the front wheel and i will one of these days but for now this works fine) from here for me it's quite simple.......... hook the red wire from the 9 volt battery connector to the red lead to the hall sensor going to the motor and the black lead to the black wire and then set you digital multimeter to read dc voltage then black test lead to black and and red test lead to one of the yellow blue or green leads from the hall sensors and then plug in a 9 volt battery and slowly spin the wheel by hand you should see a 0 rising up to 9 volts and then back down as you continue to slowly spin the wheel once you have gone through each of the signal leads (yellow green and blue) and noted the results for each color then disconnect the battery ........ heh heh heh not bad for an old beat up machinist eh? So again i ask "damn i am a machinist what do i know about hall sensor (now i know what they are) testing" ANSWER? more than i ever wanted to know And while i am on the subject............. i am wondering if enamel coated magnet wire wouldn't be a better choice for replacing hall sensors and using JB WELD epoxy to adhere them into place in the slots................. SLAPS myself on the head!!!!!!! yeah ok i get it you can't color code them when you use enamel coated magnet wire .................. but then again don't they have multi-colored heat shrink tubing? i don't know back to the internet and scope it out i guess