General Carvon Thread - V3 - V4 SD - V4 XL and future products

Aha I was wrong, completely ignore my entire post :slight_smile:

Good tips guys thanks. What kind of failure what that lead to on the VESC? DRV?

1 Like

I actually don’t know much about why shorter battery wires are important, though, I have heard that it’s more sensitive for FOC.

2 Likes

Doesn’t sound like the type of thing to cause a major failure, maybe an overheat if the voltage spikes waaayyyy to high but I don’t think that will cause any drv errors although most drv errors come from over voltage because of FOC. :thinking:

1 Like

Well Im running big power through my VESCs at 12S FOC and eRPM’s above 60K and (knocks on wood) haven’t had any unexplained failures yet.

@GrecoMan tell me more about these overvoltage errors using foc. Are these occurring during heavy braking?

1 Like

Yes, it usually happens during hard acceleration.

I would not recommend FOC on anything other than a vesc from @chaka as he makes his out of very high quality components

really? curious what erpm you’re running what’s your setup? mine started failing at 47k

Shoot, they hiring? Lol

3 Likes

28 Pole 130KV hubs at 12S FOC. The math says way over 100K erpm.

1 Like

That’s actually about 80k erpm, which is definitely over 60k.

My guess is that your not hitting full erpm when riding given reduced efficiency. How fast are you going and how large are your wheels?

Aren’t you using carvons? i thought they were 14 pole

I wish chaka could chime in as I forget his explanation as to why, besides that he said it is harder on the caps (more likely to blow one). If you lose all of your caps, idk what would happen. Maybe it’ll just die, idk. Just passing on the advice :slight_smile:

I hit 39mph last night. 90mm wheela and enough motors amps to break traction at take off. 37.5 battrery and 130 per motor.

4 Likes

The carvon build is still in progress, the build Im referng to is with Dexters new hubs. His older version was 14P the new ones are double.

3 Likes

Ugh… your killing me over here, haha.

If I could have some danm luck, maybe I could be riding already. One motor re-wound, expoxied, and sensored. Did the same to the second, and found out it fails sensor detection. These little guys are so sensitive, that it’s easy to weaken the legs on installation and fuck it up. So I just spent 3 hours installing it and an hour ripping it back out… Ugh, diy eboarding is so much fun :sob:

2 Likes

Doing the math, if you’re hitting 40mph, that’s about 52.8k eRPM, so you technically would still be under the limit.

Why is the esk8 calculator giving me higher numbers?

1 Like

are you multiplying by 28? For a 28 pole motor you should be multiplying by 14 pole pairs.

I didmr realize the esk8 calculator wanted pole pairs.

When i do the math I still get 91k= 50.4vdx x 130kv x 14 pp. Are u calculating based on nominal voltage?

1 Like

Yea, with your amp draw you should as well because you’ll never reach 50.4 voltage under any load.

You could split the difference and calculate with 47v

Well the specific situation I was considering was fully charged a free reving with wheels off the ground. Pretty much everyone I let try it does this to my board one time or another. Will drvs dry under high erpm low load sitiations?

Well if Im not above 60K thats good news to me. Still pretty high though right?

As far a only running FOC on chakas units I dont agree. The FOC box has been very robust for me and many others on FOC. Also consider that the Raptor2 runs on it and FOC.

1 Like