MXUS 3000 Hub Motor - V1 V2 V3

[litespeed]

Do you think I could have hit temps to damage internal stuff at only 120 on the covers?

Guess I really should get either a CA V3 or a MaxE so I know what kind of temps I'm reaching.

Hmmm.....

 

[teslanv]

Do you think I could have hit temps to damage internal stuff at only 120 on the covers?

Guess I really should get either a CA V3 or a MaxE so I know what kind of temps I'm reaching.

Hmmm.....

Yes, if the covers are 120, the stator will be hotter. Hard to say what might be damaged. A CA V3 with temp sensing properly programmed is a very good idea.

 

[macribs]

Do you think I could have hit temps to damage internal stuff at only 120 on the covers?

Guess I really should get either a CA V3 or a MaxE so I know what kind of temps I'm reaching.

Hmmm.....

I would assume that is exactly what happened. 120 on the outside, well you got to figure inside will be way higher. After all wheel is spinning and get some cooling help of the breeze created by the speed. And as this is the second time you loose your halls I would say more cooling is needed, or less throttle/abuse.

Btw I thought 120 or there about was max temp for all internals even magnets. Why repeat heavy tasks all the way to something gives?

Both adaptto or the CA v3 seems like a very expensive options for a simple task if all you need is to monitor the internal motor temp, assuming you got a working programmable controller already. Why would you need two?
To see what temps you are reaching you could easily get away with a 5$ BBQ thermometer. You could even have audio signal when temps hit whatever limit you set - then you will know when to coast and glide at high speed to let things cool down.

 

[madin88]

madin88 - Wow you must be heating up your motor a lot.

It's about losses between controller and motor because of to small phase wires.
I'm quite sure everyone that uses a Max controller together with this motor has set above 200A phase - at least in boost mode, and with stock phase wires above 600W are puffed into the air.

 

[John in CR]

- if you do not want to go fast (as ex fat bike) than a slower motor will offer more system efficiency -> right

Wrong, as is the now often repeated "slow winds are better for big wheels", and every other different wording of the same tired myth. Yes, as I've said many times controller limitations at both ends of the spectrum can make slow winds more convenient for slow and low power, and fast winds more convenient for fast and high power, but everywhere in between they're effectively the same motor. It took me quite a while to fully let go of all facets of the myth despite equivalence of the motors staring

Of course if someone is running high current at a minimum they should upgrade the wires starting just outside the motor, and I have little doubt that some type of wire upgrade is commonly suggested to Teslanv's customers.

If controller cost is what you want to hang your hat on, then I'd counter with the fact that more controller can be had for less.

If you want to talk about overall system efficiency, then of course everything needs to be properly sized for parity, but controller tuning is of far greater importance for efficiency, since the vast majority of losses are in the motor. The slow cruising types should try a fast wind motor at less current than the turn count ratio would dictate. Use a higher voltage than the ratio warrants, but limit the top speed in the controller. The result will be greater overall efficiency, smoother take offs with better acceleration through the mid-range to top speed. I've lived with 2 turn motors with 40mm stators of the same basic design for almost 7 years, so I know how to get any result desired within the motor's capabilities. I still have all 5 motors in different implementations alive and well, 2 in small wheels and 3 in larger wheels than I'd prefer. I have some slow wind motors too, so I know first hand that there's nothing a slow wind motor can do that a same model fast wind motor can't do as well or better.

On the subject of inductance, I finally tracked down my inductance meter, and my 2 turn motors have a phase to phase inductance of 90uH. I've only had controller heat issues with Infineon board controllers driving these and other low inductance motors. Considering the extra turn, mutual inductance, and the wider stator, I'd expect the 3T's inductance to be close to double, which should put it in a safe range... maybe not running 24s with a 100V component controller, but I always discourage that anyway.

If the extra 2m and 20 strands instead of 21 were included in the measurement to get to 70mOhms for the 3T, then that accounts for enough of the resistance difference that the WYE and phase terminations probably didn't miss any strands. I would like to know how they make the magnet wire terminations, because I didn't see that step in the video of Justin's visit to 9C, and I'd like to be able to reliably join bundles of magnet wire. How do they strip the varnish coating, and how to they soak the bundle with solder?

 

[John in CR]

I'm quite sure everyone that uses a Max controller together with this motor has set above 200A phase

If true then they're following bad examples or bad advice. That's the kind of stuff I mean about properly tuning controllers. Making thousands of watts of heat in the motor is begging for failures.

Litespeed's example brings an issue with slow wind motors, which is that they're so easily pushed too far. Not that I'd recommend it, but I've pushed a couple of my 2 turn motors all the way to full bog down on steep hills a number of times without a motor failure.

Litespeed, no amount of cooling will save your motor at those controller settings. Your batteryhase current limit ratio was nice and conservative, but you're starting with a battery side limit that's way too high. Be sure to replace the complete wiring harness when you change the halls, because it's quite likely the wire insulation suffered heat damage, especially the the hall wires, and as stated above, get yourself a temperature sensor. Pushing for performance without a temp sensor requires time and patience to learn the operating conditions that create heat in order to avoid them and tune your controller using small increments to prevent them. Ventilation can help, but it's no cure-all, and simple calculations can tell you how much heat a given air flow can carry away with it. It's a disappointing eye opener. The only reason I can run the crazy power I do is because I use current settings that ensure I never make as much heat as you were making in your motor for more than 2 or 3 seconds. You made the big heat essentially continuously from the start of the tow, and failure was so quick that no appreciable heat had even made it to the covers.

 

[Rix]

@Rix I might be 2 drunk to understand this, but I always thought John in CR was a high voltage man? I've seen several posts where he runs way more then 100v. Does he have a new build that is running 48v? Oh well 1 in the morning and my glass i almost empty. Time for bed, I will check thread tomorrow with a heavy head and fools remorse ...

Except for my SuperV, which I run at 30s (111v nominal) for going on 2 years, all of my other ebikes are and have been 74V nominal (20s lithium polymer or 23s lifepo4) since 2008.

While I could probably figure out a way to run a 26-29" wheel and reach 60mph on 48V, I'd never do it because I'd take a big hit to overall efficiency trying to get to the acceleration I've come to expect.

Thanks for clarifying, I though you had some secret holy grail combo that no one ever heard about. I was starting to doubt myself as I try to follow the most current trends in ebikes and totally missed something. Now I can go back to consuming adult beverages :lol:

 

[litespeed]

Litespeed, no amount of cooling will save your motor at those controller settings. Your batteryhase current limit ratio was nice and conservative, but you're starting with a battery side limit that's way too high. Be sure to replace the complete wiring harness when you change the halls, because it's quite likely the wire insulation suffered heat damage, especially the the hall wires, and as stated above, get yourself a temperature sensor. Pushing for performance without a temp sensor requires time and patience to learn the operating conditions that create heat in order to avoid them and tune your controller using small increments to prevent them. Ventilation can help, but it's no cure-all, and simple calculations can tell you how much heat a given air flow can carry away with it. It's a disappointing eye opener. The only reason I can run the crazy power I do is because I use current settings that ensure I never make as much heat as you were making in your motor for more than 2 or 3 seconds. You made the big heat essentially continuously from the start of the tow, and failure was so quick that no appreciable heat had even made it to the covers.

So your recommendation to battery amps and phase amps is all in regards to how it heats the motor up? I have tuned R/C motors both brushed and brushless but this bike stuff is way harder due to the fact of just larger physics. Way more load at certain times just causes havoc. I suppose like everyone else that craves power just need over kill sized motor and run it at a reasonable power level for its size to add any sort of a safety net. Looks like I should learn all the ins and outs of what Evers motor capabilities, pick a controller that fits it best and go from there. My battery is the pivot point right now because I don't want to have to reconfigure it. 24s and 22.5 amps in very conservative 10C continuos 20C burst Konion pack.

So if I was to get a 9 to 12 KV motor and run it in a 17" rim (I really wanted to go to a 19" rim to look less obvious!) at 100 volts your tuning regimen is what exactly? Looking for 50 mph top speed and 20 mph all day drive abilities.

Thanks,

Tom

 

[Rix]

Litespeed, no amount of cooling will save your motor at those controller settings. Your batteryhase current limit ratio was nice and conservative, but you're starting with a battery side limit that's way too high. Be sure to replace the complete wiring harness when you change the halls, because it's quite likely the wire insulation suffered heat damage, especially the the hall wires, and as stated above, get yourself a temperature sensor. Pushing for performance without a temp sensor requires time and patience to learn the operating conditions that create heat in order to avoid them and tune your controller using small increments to prevent them. Ventilation can help, but it's no cure-all, and simple calculations can tell you how much heat a given air flow can carry away with it. It's a disappointing eye opener. The only reason I can run the crazy power I do is because I use current settings that ensure I never make as much heat as you were making in your motor for more than 2 or 3 seconds. You made the big heat essentially continuously from the start of the tow, and failure was so quick that no appreciable heat had even made it to the covers.

So your recommendation to battery amps and phase amps is all in regards to how it heats the motor up? I have tuned R/C motors both brushed and brushless but this bike stuff is way harder due to the fact of just larger physics. Way more load at certain times just causes havoc. I suppose like everyone else that craves power just need over kill sized motor and run it at a reasonable power level for its size to add any sort of a safety net. Looks like I should learn all the ins and outs of what Evers motor capabilities, pick a controller that fits it best and go from there. My battery is the pivot point right now because I don't want to have to reconfigure it. 24s and 22.5 amps in very conservative 10C continuos 20C burst Konion pack.

So if I was to get a 9 to 12 KV motor and run it in a 17" rim (I really wanted to go to a 19" rim to look less obvious!) at 100 volts your tuning regimen is what exactly? Looking for 50 mph top speed and 20 mph all day drive abilities.

Thanks,

Tom

Confirm you are running 24s with what motor? For sure 4t will get you 50mph and 5t may as well. If you keep your amps limited to 50 or less, a 4T should work for you on a 19mc wheel, provided you use a little mechanical sympathy.

 

[macribs]

@John in CR can you take a look at this possible setup, to see what voltage you would recommend and what controller would be a good match for this motor.

@Everyone else feel free to pitch in about the controller you have used with the mxus 3000 motor, what voltage you run and what A limits you had. What kind of output power did you see when pushing it?

So with a mxus 3000 DD hub, let's use the the 4T motor in this example as the 3T have turned up with less copper for ie madin88. And let us use 17" motorcycle rim, with 3" tire for this exercise. So we have wheel size and motor locked in. What we don't have locked in is battery voltage and controller. Overall goal for this exercise is to have as much acceleration as possible, decent top speed and a fair life expectancy of the motor/controller.

It seems like the Adaptto max-e is now almost the defacto controller for hi power usage. I've seen you mentioned a time or two the use of less costly controller while still having hi output power.

1: What battery voltage would you recommend?

2: What controller would you recommend if goal is more then 10 kw from this motor (mxus 3K 4T) ?

3: What modifications (if any) of motor would you say is a must/crucial to have longevity despite high power output? (thick phase wires, ventilation..)

4: What modifications (if any) do you do to your controllers when running them in > 10 kw setups?

Feel free to mention any and all controllers you have had good experiences with, no matter who manufacturer the controllers and who sell them. If you have controllers for sale worth mentioning pls do mention them. The point here is to see what real life options (if any) there are to hi cost controllers like Adaptto.

 

[Cowardlyduck]

Cool your Adaptto controller like this:

Cool your motor like this:

Cheers

 

[litespeed]

Confirm you are running 24s with what motor? For sure 4t will get you 50mph and 5t may as well. If you keep your amps limited to 50 or less, a 4T should work for you on a 19mc wheel, provided you use a little mechanical sympathy.

Right now I have a 6T in a 17" motor rim with a Shinko 3" 244 tire. Sounds like I need to do a 4 turn MXUS or a QS 205 or 273 motor with the same KV.

Tom

 

[Rix]

Cool your Adaptto controller like this:
http://

Cool your motor like [url=http://endless-sphere.com/forums/viewtopic.php?f=30&t=56965&start=100#p1009434]this[/url]:
[img]http://s30.postimg.org/5odro0kox/P1070421.jpg

Cheers

I have been meaning to ask you, do you think your motor would cool as well with say 3 fans? I ask because I am a big believer in vented hubs, and my experience thus far is when a vented motor gets hot, riding it on the road at say 1/3 throttle with no load seems to cool them down quickly. Much quicker than if the motor wasn't vented at all. But I wonder if that just because of air flow, or the fact that the vents facilitate a means for heat to exit the hub. Anyway I remember you posted some data about forced cooling and voltages fed to your fans, and there was a point of diminishing returns where increasing volts didn't decrease cool down times.

 

[madin88]

I'm quite sure everyone that uses a Max controller together with this motor has set above 200A phase

If true then they're following bad examples or bad advice. That's the kind of stuff I mean about properly tuning controllers. Making thousands of watts of heat in the motor is begging for failures

I think everyone knows that 200A are far away from optimal tuning for this motor (4T in my case), BUT IT MAKES FUN, and what i was trying to say was it makes even noticeabel more fun with upgraded phase wires, because the motor is stiffer and has higher torque at given RPM's would you not do this if you would have a controller with different power modes and capeable of 10kW+??
In Normal mode i have set 60A batt and 110A phase and in Eco mode 40A batt and 80A phase. this is way more optimal for this motor, but i would not want to miss the not so efficient adjusted boost mode^^

Litespeed, no amount of cooling will save your motor at those controller settings. Your batteryhase current limit ratio was nice and conservative, but you're starting with a battery side limit that's way too high.

thats the problem: 70A batt continuous and no thermistor. this is like pushing the 4T at 105A or the 3T at 140A. no wonder the motor almost got toasted!

 

[John in CR]

Macribs,

Your requirements are too vague to make any recommendation, and Teslanv is the guy to get them from, since he has direct experience with the motors.

Litespeed, Macribs, et al,

For performance builds with any hubmotor I can't stress enough the importance of using the smallest diameter wheel you can possibly live with. Performance requires power and the overriding limitation of hubmotors is thermal, and the overwhelming majority of heat in a hubbie comes from copper losses. Copper losses are motor current squared times resistance. Power is torque X rpm, torque has a direct relationship with current, so trying to get more power through greater torque is a losing battle with heat going up by the square of current.

That leaves increasing power with rpm, ie voltage. At hubmotor rpms heat goes up by small amounts with rpm, but you can't just stick with the same size wheel, since losses to the wind increase geometrically with speed. If you decrease wheel size proportionately with increased rpm then for the same top speed you have proportionately more power on tap with the same current limits, and at any given speed the motor will have a slight increase in core loss from the higher rpm than before, but significantly less copper heat since the torque (current) requirement decreases proportionately making copper losses decrease by the square of reduced current. That means efficiency is greater.

Unless our rides are mostly at steady state cruise on flat ground, a huge chunk of our energy use and heat creation occurs during acceleration, which includes climbing hills even at constant speed (accelerating against gravity). Running a smaller wheel has the same effect during acceleration as reducing the total load the motor pushes, so with the same current limits the acceleration times will be shorter for less energy use and heat generation, or you can reduce current levels proportionately for the same performance using less energy and generating less heat, or go somewhere in between and get better performance and better overall efficiency.

Other benefits of higher rpm are that the motor sheds heat better, and when combined with less heat generation lower temperatures is the result. That further increases efficiency over the bigger wheel, since copper resistance increases with temperature by about 0.4% for each 1°C increase in temperature.

While the extra copper in the slot makes the 4T have a slightly greater peak efficiency, with full size bicycle wheels that only comes into play at steady state cruise at modest speeds. The 3T makes it easier to get performance (if speed is a primary gauge) with the faster spinning smaller wheel without exceeding a threshold of 22s or 23s where controllers jump in price.

FWIW, I practice what I preach. My daily rider, a Cannondale SuperV with a custom swingarm has a 19.25" OD wheel, and with my passive ventilation approach it only exceeds 70-80°C under the hardest riding conditions pushing my 400lb+ all up load. The highest I've seen is 105°C. 2 other bikes have under 20" OD wheels by using 14" moto rims and tires, and those will both hit 60mph with motors like the MXUS V1, but only 40mm wide. The sealed one I have to keep riding conditions in mind to avoid heat problems.

A truly amazing small wheel result is with a motor from a junky lead pig ebike/scooter that has a built on rim with a tire 16" in OD. It has only a 20mm wide stator, and was restricted to a Euro-legal 15kph on 48V. We gave it 74V of lithium (a bunch of old very used stuff so still fairly heavy at about 110lb total for the scooter/ebike thing) using a 30A 9fet controller. It will push even fat me up to almost 30mph on the flats, but my daughter used to climb steep stuff with it, as well as haul a passenger up slight grades, not bad for a small 9C style 9Kv motor. That motor is still sealed, with the only improvement a wire upgrade outside the axle.

 

[Cowardlyduck]

I have been meaning to ask you, do you think your motor would cool as well with say 3 fans? I ask because I am a big believer in vented hubs, and my experience thus far is when a vented motor gets hot, riding it on the road at say 1/3 throttle with no load seems to cool them down quickly. Much quicker than if the motor wasn't vented at all. But I wonder if that just because of air flow, or the fact that the vents facilitate a means for heat to exit the hub. Anyway I remember you posted some data about forced cooling and voltages fed to your fans, and there was a point of diminishing returns where increasing volts didn't decrease cool down times.

I don't want to spam this thread so I'll keep it short.

It would still work well with 3 fans. My previous setup used 6 fans at half the CFM of these 6, so the equivalent of 3 of these fans. It's all about air flow...Offroader is doing it with 1 fan, but it's a high speed EDF that screams and blows a gale.

You should follow the fan cooling thread for details:
http://endless-sphere.com/forums/viewtopic.php?f=30&t=56965&start=100#p1009434

Cheers

 

[Samd]

Suggest only cutting holes in your motor if you can't get the ebikes.ca simulator to not say "overheat = never".
It takes a lot of power to do that.

For most people, the Mxus is a gift where they can spend time actually riding instead of modding in the shed for countless hours.

 

[John in CR]

I'm quite sure everyone that uses a Max controller together with this motor has set above 200A phase

If true then they're following bad examples or bad advice. That's the kind of stuff I mean about properly tuning controllers. Making thousands of watts of heat in the motor is begging for failures

I think everyone knows that 200A are far away from optimal tuning for this motor (4T in my case), BUT IT MAKES FUN, and what i was trying to say was it makes even noticeabel more fun with upgraded phase wires, because the motor is stiffer and has higher torque at given RPM's would you not do this if you would have a controller with different power modes and capeable of 10kW+??
In Normal mode i have set 60A batt and 110A phase and in Eco mode 40A batt and 80A phase. this is way more optimal for this motor, but i would not want to miss the not so efficient adjusted boost mode^^

Yes of course on the wire upgrade. I have 4 AWG welding cable ready for my next built, and keep in mind it's 6 of them for my phase wires. It adds weight, but worth every gram, just like big motors are after trimming as much fat as possible.

No, however, on spending all that money to run a motor under stress. Each half of my motor has 1/3 the resistance of your 4T, and half the torque per amp. Each controller has 123A/190A current limits, so about equal your boost mode, but 1/3 the heat. Add the 2 together and it's still only 2/3 the copper heat under the hardest riding conditions, and the same motor torque. My smaller wheel probably offsets most of your weight advantage, so launch is likely about equal, but after the first revolution or 2 of the wheel I'm gone. That's because my torque curve is so shallow from the extreme current limiting and the high voltage, which is on top of turning more battery power into work instead of copper heat, and before your significantly greater losses from increased copper temps.

For my offroad build I'll stick with high voltage, and put the same motor in a mid drive with a gear reduction down to effectively a 10" OD wheel. The top end will be more than enough at 90kph or so, but more importantly I'll be able to go down to something like 90A/125A for each controller in boost mode, which will put max heat generation at about 1100W. With gearing so low I may not be able to get it to draw full current, so with the motor ventilated but in a housing to prevent debris, there's no way I'll have heat issues, even picking my way up rocky ascents. I may give it a go sealed first with mods for increased surface area.

I included the offroad build info, because there's no way it should be run in wheel at low speed and high load needed for off road. I wouldn't matter what voltage I ran or even the small wheel size I run or how the motor is wound. It will still create too much heat, yet guys continue to try it, because it seems easy. Sure some lighter guys get away with it, but from what I've seen it's more light trail riding than the mountainous off-road I need, much less carrying the 3.5 to 7.5kwh pack I want to use.

 

[Samd]

Wouldn't those phase wire upgrades be far in excess of the effective internal equivalent AWG? By a huge order of magnitude?

 

[John in CR]

Wouldn't those phase wire upgrades be far in excess of the effective internal equivalent AWG? By a huge order of magnitude?

While the 4awg I snagged on sale is a bit of overkill it will still save 200-300W in heat loss during acceleration compared to the 8awg I have now. That's with tame settings. For the 1/4 mile run it will be at least a full hp in savings. There's no flexible wire available locally between 10awg and the welding lead wire, and 10awg isn't enough. What comes out of the motor is metric wire between 9ga and 10ga, and the controllers have dual 10ga. Heat travels so fast through copper that it's always good to have significantly larger wire outside the motor, so it sinks heat away from the motor.

In addition I have a larger 3 phase 1.5 turn motor that I've pumped 425A battery side 510A into without complaints from the motor. I was scared to push the controller any higher. The controller factory has 24 and 36 fet models for me to test with irfp4468 and 4568 mosfets, so the 4awg may be a bit light for exploring that motor's limits.

Plus this was some back of the shelf stock I'm always on the lookout to find. Many places don't adjust prices with the change in exchange rate, so this 4awg cost less than shipping and taxes would have been to bring in some 6 or 8awg good quality wire.

 

[macribs]

I think that the 4 awg will work fine. When I think back to the days of car stereo builds we used 4 and 2 awg wires all the time. Thick as garden hoses. Never thought about the phase wires as a mean to dissipate heat but it makes sense. How thick wires can you get into that monster hub? You should make a custom cooling block for the phat 4 awg wires, maybe that is all the cooling you need

 

[Samd]

Well it's not whether it will work fine or not in my mind, it's just that there's not a lot of rationale in my mind for exceeding the gauge of the phase wires by whole orders of magnitude.

 

[Stielz]

A question for you guys who have sprayed a rust protection enamel on the internals of you motor,

Would this product be suitable for that purpose?
https://www.rustoleum.com/product-catalog/consumer-brands/specialty/high-heat-ultra/

And a snapshot from the datasheet


Thinking the the black color would give improved heat dissipation from higher IR radiation

 

[John in CR]

Well it's not whether it will work fine or not in my mind, it's just that there's not a lot of rationale in my mind for exceeding the gauge of the phase wires by whole orders of magnitude.

It's not orders of magnitude, the 4T MXUS windings are wound with magnet wire in a bundle larger than 12ga and the 3T has more than 10ga worth wrapped on each turn.

The benefits are:
1. Less energy waste in heat loss in the wires for better overall efficiency. My phase wires are over 1m long so it adds up quickly.
2. Less voltage drop in the wiring for better performance.
3. Larger than what's in the motor makes it somewhat of a heat sink drawing heat away from the motor wiring where they are vulnerable to heat buildup, in the axle.

Wiring is one place where some overkill is definitely worth a bit of extra weight, especially running high currents.

 

[Samd]

Sure. For a given length of wire.

I tend to go with Barent's point earlier though.
Cut them short.