Cyrstalte HT 3540 Judder

[Trawleysteve]

Hi,
New to the site. I recently was using my bike I had been out for 40 mins warm day I had a section offroad where I was working it quite hard. When I stopped for a short rest at the top of the hill and went to move off again the motor just juddred a couple on inches and stopped. It was very hot. A lot hotter than it had been before so I thought that some sort of overheat control had kicked in. I rode the mile home but even after this it would not work. I left it for a day thinking it was just heat related but I have charged the batteries but still the fault. it judders round 1/4 of a turn and stops. The battries still had 40% when I first got the fault so I dont think it is that. I am running a Cyrstalte HT 3540 at 72v max 60amps with a Lyen custom spec speed controller and a Cycle Analyst 2,23. Does anyone have an idea of what it may be?

Thanks,

Steve

 

[bowlofsalad]

Unplug the connectors, check them all for bent pints, loose fits, corrosion, thinks like that, reconnect them each a few times and check their continuity using a multimeter. Do not let the bunch of connectors sort of just hang free or problems may arise.

If that doesn't fix it, http://www.ebikes.ca/learn/troubleshooting.html check this page. I might start with checking the hall sensors.

As a 'welcome to the forum' note, make yourself familiar with searching for things on this forum, as I am sure you and others will have plenty of questions that have been asked in numerous occasions. There is a 'using google search' just below the search box which both resides in the upper right corner of this web page. Do searches with and without google as you'll often find different and potentially interesting results.

 

[xipi]

Hi Sounds like you burnt out the motor or hall sensor has failed

Open the motor on the other side from the cable entry have a quick look if the windings are burnt motor is Junk



Frank

 

[kenwood96]

Probably burned hal sensor, I think you can't put more than 30amps continuesly with that kind of voltage.


While replacing the halls, you could seal the motor up and fill it till just under the axle with mineral oil.


Helps against corrosion and you can put some more amps thrue it without burning

 

[izeman]

yes 4kw is too much for a long time. 2kw is ok for a longer time - shouldn't overheat (at least not on the flat)

 

[ecycler]

Yep, that is too much power to put through a 3540 and expect long term reliability without monitoring temp.

 

[ecycler]

Also, it always seems to happen after a hill or WOT run. I think it is best to coast down the other side of the hill or ride slow (NO REGEN) and let the motor get some cooler air rather than stop at the pinnacle of the heat soak and let it sit there and quietly cook.

 

[Trawleysteve]

Thanks for the reply's,
Stripped the hub down today. Windings are burnt out. Any thoughts on the most cost effective option; have it re-wound, new stator if available or an alternative motor. I am mainly using it off road in the hills.
Thanks,

 

[bowlofsalad]

Thanks for the reply's,
Stripped the hub down today. Windings are burnt out. Any thoughts on the most cost effective option; have it re-wound, new stator if available or an alternative motor. I am mainly using it off road in the hills.
Thanks,

A new motor is likely the better route. The permanent magnets get demagnetized under too much heat as well, basically everything within the motor is probably damaged beyond the housing and such which can be sold for scrap. You would probably be wise to find a motor that might be up to the task for you but also includes a temperature sensor, or you could just get another of the same motor and add the temperature sensor yourself. A setup involving a cycle analyst version 3 with automatic thermal roll back might be up your alley. We call it venting a motor, which is when the side covers of the motor have several holes drilled into them and then the inside of the motor is sprayed with http://www.amazon.com/gp/product/B001447PEK/ref=as_li_tl?ie=UTF8&camp=1789&creative=390957&creativeASIN=B001447PEK&linkCode=as2&tag=xbnijgbr-20&linkId=GAIEOFIMVNFBY2IJ something like this. Venting a motor increases it's power capacity by around 3 times, but if you want to play it safe, and you will continue to climb lots of hills, I'd probably say that the power capacity of the motor would be increased through venting by twice it's original rating. I guess you could end up playing things by ear and seeing what the temperature sensor tells you.

Motor efficiency is directly tied to RPM https://www.google.com/search?q=motor+efficiency+curve&sa=X&biw=1920&bih=856&tbm=isch&tbo=u&source=univ&ved=0CB0QsARqFQoTCMe9v_qQ8McCFUlbHgodBc8BzA&dpr=1 Some pictures here may help illustrate. The lower the efficiency the more heat is generated rather than propulsion. Add to that the slower you go, naturally, the less air is moving over the surface of the motor. Each hill is different, just like each day, which is why I would recommend not doing without a temperature sensor in your case. I guess I see the increase in cost and potentially avoiding the hassle of dealing with a broken motor as well worth the cost of a temperature sensor.

 

[Trawleysteve]

Thanks for that info.