Looking for hubmotors

“Motor: brushless no sense motor”:sweat_smile: funny guys…
btw: what do the sensors do? are they useful??

sensors just tell the speed control where the motor is and which phase to light up. once the motor is turning its not that useful, but if the motor is stationary it helps to get it moving smoother.

Why is the FOC limiting you to 18 mph? I haven’t tried the carvons in FOC, but I have tried hummies in FOC and no limit as such.

What battery do you use with hummies hubs ?

I tried my modified space cell (pulling 50 amps instead of 30 amps), which is a 10s. Ok success, but then I tried 2x 8000 mah 6s zippy lipos in series to get a 12s, which can pull more amps than I need, and at 12s with the lipo, they are beasts. Torque is great, speeds are pretty good (haven’t really topped of the speed yet).

yes, the drv and mosfets get hot, that is the limitation of the v4 vesc which will be fixed in v5.

How does FOC create drastically more heat? It seems like it should create less. RunPlayBack mentioned nothing about heat. It doesn’t seem like a heat issue to me, cause if it was, when he hit 18 mph, it would roll back, and be un-usable for 15-20 seconds. Then the problem would come right back after less than a minute of riding, even if he never gets close to 18 mph. The carvons are also more efficient as they get to higher speeds, since they are 149 kv with no gearing. So as the speeds increase, you should get less heat per amp, no?

Have you ever experienced heat caused draw back on a vesc before?

If he’s getting that at only 18 mph, I would imagine it could be experienced at lower speeds with slightly more time, and it wouldn’t be practical to ever use FOC, since you wouldn’t get much riding time before heat becomes an issue.

the drop on speed is speed is a big one, the culprit here is the DVR8302 once it gets hot does not work properly.

The DRV is not the main processing unit.

Nice to know

how do you monitor temp while riding? youre not riding at full throttle carrying a laptop I imagine! Id like to check on this temp increase also. with just my fingers checking the fets occasionally I notice almost no heat. not so scientific. I thought that’s where id most likely have heat build-up, no? im on foc too
(constantly second guessing potting these)

no offense, but the temp argument just doesn’t add up to me…

You wouldn’t just get a limit of speed at a certain point, you would have issues with riding at lower speeds for longer times too. You also don’t want to keep pushing that upper limit, can’t be good for the vesc. So it would make FOC useless for the carvons, which would be a big downside of the carvons, as I don’t have this issue with hummies motors. I have been up to 25 mph so far with his motors in FOC, and no draw backs from heat with the vesc.

Also, the carvons become drastically more efficient as the speed increases, meaning you need less torque for the same increase of speed. less torque means less amps, and less amps means less heat. Yes, as speed increase, even with more efficiency, you still get higher amps than before, but limiting at 18 mph seems extreme for the heat. I have a feeling the bottle neck is somewhere’s else.

Have you ever experience heat induced draw back from the vesc before? After 15 seconds of waiting after the heat draw back, you can’t go very fast at all before heat is an issue again. It makes riding at any speed difficult once they get hot.

Plus, if heat was the issue, there’s ways of dissipating the heat, and removing that issue. So it doesn’t add up in my mind unless I’m missing something…

@Hummie for monitoring temperature on VESC all you need is free afternoon, Velcro , usb cable and laptop.

@evoheyax the temperature "argument "is an observation of the BLDC temperature feature of the components in the VESC that can be monitored. after a series of rides with the same setup and just changing from BLDC to FOC. I was not using carvons but u have sk3 6374 motors wich are the base of the carvons.

This observation does not clear the issue about the drop of speed or the temperature behavior but the fact remains that in FOC mode there is the drop in speed and that the DRV8302 keep getting failing while on FOC.

So lets get more people riding with laptops and try to figure this out.

isn’t it possible to have some memory with the vesc? plug in a usb stick or something or even internally. going full speed with a laptop plugged under my board would make a cool photo though.

Dude on the deck, not under it. :slight_smile:

I was planning on watching the screen with my wire connected to my vescs under the board. that’s the cool photo. maybe check in on esk8 too while im on the machine.

Your chihuahua can Help with this task

that dog, which isn’t mine, will do anything for food and he’s in training and has been riding. if he was mine honestly he’d have been put down long ago. he’s been racking up lawsuits for bites and is on strike number 3. 3700$ went to the lady across the street for mental trauma. cuteness is the only thing keeping him alive.

im not out of stock of hub motors either by the way. (you posted I was above). trying to send them to anyone who wants to give me 200 for the pair…and you get the guarantee with the steel at 225 later.

Are those with drv failing getting them from chaka? I have a feeling they are subpar drv chips, and that is why. Niether hummie nor I have had any issues with hummies motors in FOC, we’re both using chaka’s vesc’s.

I might wait until the v5 vesc’s to get a pair of VESCs for the carvon’s, as I’m sticking with hummies motors for the vesc’s I have. v5 might also fix this problem :slight_smile:

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Waiting fir V5 too