Temperature cutoffs with Lacroix Nazaré motors

Acceleration temperature decrease was implemented years back, so that there is always headroom for the brakes to work. The problem we had before that implementation was the loss of brakes when the motor or ESC reached cutoff temp. Now the acceleration is decreased x percent before you reach the final cutoff value. As standard that is 14% and it affects motor and Mosfet temp. You can’t accelerate any more, but brakes still work.

Going higher with the final cutoff temp helps a bit, since the power decrease is ramped in a linear way in between cutoff start and cutoff end. The further these values sit apart, the less power is reduced in the beginning of the temp protection. However, once the motor is too warm, the FOC detection parameters are possibly not matching the real motor resistance values any more. The hot motor has a higher resitance… Without FOC temperature compensation you could enter the trouble zone after x °C temp rise. If you start riding with a 20°C motor and you increase the temp by 90°C, the resistance of the motor could have changed by more than 5%. And that value should be 5% precise for FOC operation.

Also there is that effect that a hot motor is running less efficient and generates even more heat. Once you enter that state, a higher value for Motor Temp Cutoff End will not help a lot. Maybe you gain a couple of minutes in ride time…

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Naw, you’re good. The Stormcore is intended to be user configurable, you should just be very careful in making changes to your config. It’s not something to do without doing your research and understanding the changes you’re making (which is why you’re here :wink:)

If you’re on iOS (or Android) you can use https://FreeSK8.app to change settings/check stats

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Thanks, I will check the freesk8 app.
All these settings and the meanings behind them are very overwhelming but I shall persevere :wink:

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The fact you even said this means you already starting to understand parts. There’s a lot of confusion. VESC It’s well known for its interface not been user friendly and confusing labaling.

I’d drop the motor temp cut off start down a bit this will reduce the available power earlier as things heat up and should take longer befor you hit the cut off end.

It’s a matter of playing around with what works best for you and your set up.

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Definitely but there’s so much yet to learn.
Also, I’m very bad a understanding something from written text, especially if it is something technical like the duty cycle.
I bet it will come to me with time.

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I believe @Trampa have some videos on the VESC tool and how some of it works. Can’t remember were but hopefully some one can drop a link.

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I’ll check them out, thanks!

Addendum:

I found out that the motor cutoff temp is at 110C and I definitely hit that.
Today I was out again and I had brought my temperature measuring device, when I checked it said that the motors had a temperature difference of about 10C which is odd.
I thought maybe it was because the cooler motor had a looser belt which was slipping under heavy braking and the other one was quite tight.
Sounds kinda sensible.
Other than that I didn’t have cutoffs today because it was quite cool.
Otoh I’m losing range fast because of the cold :sob:

Ok, so it’s getting warmer over here and I have long stretches of road I can just open the throttle on and let er rip.
I‘m getting these cutoffs again and it sucks.
As I am now sitting on a curb letting my momos cool, I noticed the right motor was much hotter to the touch than the left one?
Does anybody know why?

Check the bearings, it might be time to replace those. Do both motors freewheel smoothly?

Motor bearings are to be treated as a consumable, especially on belt drives.

I run 6396 maytechs myself and weigh similar to you. I’ve removed the big support bearing and mounted the motors on a set of finality GDs. Have not had any overheating issues unless it gets hot outside (+35c) since then.

The big bearing is likely to fail and cause additional friction. Gear drive adds additional support to the motor shaft and also acts as a big heatsink.

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I will check that, thanks.

So it looks like the big support bearing‘s fucked.
Luckily we‘re in for bad weather and cold so I’ll be in my garage, changing bearings and while I’m at it, get some proper steel motor pullies, alu sucks.

Some notes here that you might find helpful …

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Thanks, already found it.
Now I have a semi disassembled board on my work bench.

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Edit: I think my belts were too tight but all of this does not bode well for summer.

Ok, so new motor, steel pullies and new belts, continued riding and my motors are at 93 def C according to stormcore, I burn my fingers touching them.
What the hell, I don’t want to stop every 12 or so km and let the motors cool!

What in the hell

That makes no sense, how would the motors get that much hotter than the esc? Is it because of the giant heatsink plate in the enclosure?

I dunno. They are smolderingly hot, the esc is bored shitless it seems.

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I remember this all too well when I had the 190kv. Im using the 130kv on the supersport, i dont have a temperature reading, but i can rip around for over an hour with no issues, and the motors don’t fry my hand immediately upon touching like the 190kvs do

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That’s what I was starting to think, the 190s are just too brutal and get way too hot, I may switch to either 63100 or lower kv ones.
I’d have to change the motor configuration in the Vesc like acceleration and braking then, right?

I think you’re going to have more problems with 130kV, the 190kV has more copper fill and can support a higher continuous current rating. I think you’re better off with a different motor altogether (reacher / flipsky bh)