Toasty!

[sflorlando]

HS3540 ran hard at 74 volts and bursts up to 60 amps. On the way home I can feel the motor get "spongy" pressing the throttle didnt seem to do anything, so I killed the engine and pedalled home. When I got home and opened it up a few days later this is what I saw.

So is it blown?

Thanks guys!

 

[knoxie]

yep sadly although I have seen worse and this could still be your controller or BMS if you have one xlyte must love this forum yeah motor was never designed for that sadly...temp sensor would have bee a good idea, ahh well you live and learn, you tend to remember what hurts you in the wallet and learn from it I have broken and burnt so much kit in the past, luckily for me most of it I was testing for other people so it didnt matter my wallet at least, hope you get back on the road soon.

Cut down one side of the white braiding on the motor phases and check that the joints are still soldered? some of the joints there can go bad under high power, its one of the first things to check, there are loads of threads on the forum to help you diagnose the problem have a really good dig around as people dont like to go over old ground over again.

 

[MadRhino]

Look like it.

What were the ride conditions and duration?

Was that with your 24 fet controller?
If so, you might have fed much more than 60 Amps at times
Do you have a CA, or recorded somehow your power usage during the ride?

 

[Kinni420]

Ive seen fried car starters. Looks much the same

 

[sflorlando]

thanks guys. Yes I have a CA, that was set for 60 amps max. with the 24 fet also set to 60 amps.

Well I guess I need that cromotor now!

 

[Pure]

Lol I told you not to push that thing over 3500K.

 

[MadRhino]

I am still interested to know the ride conditions and duration.
My H motors are running with 100v 100A, yet I monitor temp for they are quick to overheat. :wink:

 

[dogman dan]

Ya call that toasted? The string tying up the windings didn't even combust. Well, yeah, it's toasted pretty good, but I've seen worse for sure.

Could be just the halls fried. If the phases haven't actually shorted, you can still run it. I have a 9c motor that burt worse running. It just needed the phase wires soldered back on to the windings, and good as new. Even though the motor got hot enough to melt solder and burn away the strings.

 

[sflorlando]

Thanks guys.

Id hit the throttle hard for a few moments keeping an eye on the total amps. Although i set the controller to 60 amps and the cycle analyst for 60, the display would show big jumps up to 40 amps. Wouldnt go past it, just close. I looked at the wattage and although the torque seems twice as high the wattage got to around 2800 max. I sort of thought that the analyst may have to somehow be re calibrated but I ran it for like 6 miles and it seemed fine. I didnt know the temp of the motor so I pushed it hard for a few minutes, then id flutter the throttle on and off to keep it to constant speed.

I was just a few blocks from the house on a slight decline...I pushed it and wanted to see it go to 40+. I think I hit 45 and then it got slow. Didnt move much when pushing the throttle....so I stopped and did the shameful pedal ride back home.

Before taking it apart, I tested the hall sensors. They seemed fine adjusting in voltage as I spun the wheel.

I then checked for continuity between green phase and blue phase. They were shorted. Yellow doesnt seem to be. I looked at the wires and I do see some damage on the wires, with nicks and burn marks. I seperated all the wires so that they were not touching and checked for continuity again. Still the green and blue showed shorted so I thought that the windings may have been damaged.

Ken

 

[Harold in CR]

Hate to see that happen.
If you decide it's bad, and want to not need it, I would be interested, mailed to Vero Beach.

 

[John in CR]

When performance falls off from getting too hot, you shouldn't just shut it down. Lift the wheel and run it no load to get the motor cooled down much quicker. Shutting it down slows cooling greatly...no more air spinning around inside or outside, so the motor roasts for quite a few minutes.

 

[MadRhino]

...I looked at the wattage and although the torque seems twice as high the wattage got to around 2800 max. I sort of thought that the analyst may have to somehow be re calibrated ...

My 24 fet was feeding much higher power than it was set to, sometimes. My CA was acting weird when this happened showing huge watt reading and more real numbers in alternance. One thing I know for sure: When you have twice the torque, you're feeding AT LEAST twice the power.

 

[dogman dan]

Hmm, seems kind of odd that your motor cooked off that fast. I sort of assumed you had gone for a longer ride. Lots of stops and starts? Bummer it actually shorted the windings. Guess down inside you did get it quite hot.

Too bad you can't just buy a stator on the cheap. Some of us have a good collection of spare cover plates and rotors nowdays. But you could maybe get an unlaced motor a tad cheaper, then just slap it into the old stator that is laced.

 

[sflorlando]

I never even thought about getting an unlaced motor and slapping it in.

If it can be done cheaply that would be great. However I feel that my addiction to torque will cause me to blow the new one quite quickly.

Is there any value to a burnt out motor, perhaps someone wants to try repairing it, or can use it for scrap parts?

 

[Brentis]

I never even thought about getting an unlaced motor and slapping it in.

If it can be done cheaply that would be great. However I feel that my addiction to torque will cause me to blow the new one quite quickly.

Is there any value to a burnt out motor, perhaps someone wants to try repairing it, or can use it for scrap parts?

If you have an addiction to torque shrink that rim.
Using the Hx3540 in a 20" rim offers really good pull.
20" wheels introduce a series of issues to overcome.
For a fast ebike it is worth it.
If you use throttle more than pedal 20" or motorcycle sizes is the way to go.
More torque, more efficiency so runs much cooler.



20ft.lbs. more torque.
Down only 3mph over 26"
3.5% more efficient.
No overheating versus what you have now. How does that smell?

Just my 2 cents. Once you go small diameter/fast wind you wont go back.

 

[Pure]

Might be a good time to try what Farfle is doing with GM motors here. http://endless-sphere.com/forums/viewtopic.php?f=6&t=34880&start=15

You would be the first on the forums to do that with the H series motors.

 

[sflorlando]

Nice thread..I dont have the skills for doing something like that!

I know we all start somewhere, but I have seen my perfect visions in my mind turn out to be hideous beasts of a product when it becomes reality.

Im trying to keep my bike looking as stealth as possible.

and a small wheel may look kinda silly on a bike like mine. Appreciate the suggestion though!

 

[Doctorbass]

The only time i saw a hub motor of that size and at that low power ( 2500W) that blown was a 9C when climbed a big long hill at low throttle and speed ( poor efficiency)

The problem was finally the phase wire that had melted ( the litte gauge 16 of the 9C). they melted in the axel corner where the stator is....

The teflon melt at 260 celsius... so i guess these wires was not appropriate for that power ( 48V ping battery at 50A burst and 40 continuous)

Doc

 

[mvly]

Yeah I suspect you pushed it too hard for too long. I have a HS3548 motor and I only push it to max (~47-50mph @ 4200W) for less than 45 seconds. Then I let off to 1500W. I usually cruise at 1500W @ 35-37mph. If you were riding around 2KW or above for a long time and then push it to > 4KW, you are just asking for trouble. Ride it cool for a while and then use it full potential only for burst of speed. That is what I do. Also always pedal assist up the hills.

If you looking to push 3KW continuous, then go for the cromotor. Theses Crystalyte seems to only be good up to 1.5KW continuous.

 

[Harold in CR]

time to try what Farfle is doing

This is exactly why I asked on the first page, if you wanted to get rid of it. Contact me, if so. Lets talk.

 

[nicobie]

You are lucky it lasted that long and that you didn't cook your controller.

Going by what's written on the stator, that is not a HS3540, it's a HS3548 they are kind of like a 5302 and will take every amp you give it until it pukes. Not efficient at the speeds we run in a big wheel. Even in a 20" wheel you MUST run a temp sensor on the windings.

HS3548 are a 12x5 wind

HS3540 are 10x6

And by far my favorite the HS3525 is a 9x7 wind. Note that it has 3 more turns that the others (5% more power). I run mine at 24s lipo and it seems, no mater what I do, it never goes over 80C, and that is with 30 second blasts of over 6 kW. It's in a 24" rim with 2.5 hookworms and HOC will hit 42 mph.

 

[Pure]

time to try what Farfle is doing

This is exactly why I asked on the first page, if you wanted to get rid of it. Contact me, if so. Lets talk.

figures...speed junkie. lol

 

[sflorlando]

I bought an electric moped....

hmm....lets mod it.

 

[Kinni420]

looks like a motor has been cut out of a rim

looks like the kid can help, hand him a air gun.

 

[Harold in CR]

figures...speed junkie

Actually, a fairly decent hill climber, IF I can figure the correct windings. :lol: