Ride this Wednesday with me and I’ll tell u the kv lol. All I need to feel is the initial torque
Wednesday I can cruise at 5pm. Text me
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5pm sounds good to me!
Here:
If y’all are gonna go “feel out” your KV, maybe you can “feel out” your FOC values too 
, it will all buff out if you aren’t cereal.
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KV has a ±10% tolerance to it, so close enough :P.
You can directly calculate flux linkage too if you know the number of pole pairs.
Tbh, I forgot these were 220kv. I thought they were 200kv. I have 4, but never actually used them myself (girl boards). Why would you roll on 220kv 56xx 2wd?
That makes sense. Is the 6.44 amps? I’m learning about this stuff and wanted high end speed. Now I know better.
Volts RMS.
Kv is RPMs per output Volts pk-pk.
Yes you can. I don’t know if it’s still online but there was a pc version of he vesc tool for the unity on E ertion’s Website.
Maybe ask @Deodand for the link
In case you don’t find it I must have it somewhere.
Thank you!
Ok thanks but I do not have these tools. I have a drill only. What is the 1.3433 number and how do I get the volt (6.44) number? I think I can get RPMs in the Focbox with Real-time tool but what about the other numbers?
That’s ac volts measured at 1880 rpm.
KV is an inherent constant of a motor, right? So you can solve for X (kv) if you know the other variables.
I rogered up to measure them RC plane style largely bc I had intended to do for months.
Yes, you can pretty much feel the difference between a 150, 190, 220 kv motors.
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where? using the wizard, or the motor foc page? or where?
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If you have the ERPM measurement from VESC Tool already you can calulate the KV just by
ERPM / “duty cycle” (0.95) / “polepairs” (usually 7) / “volts” (you can use the VESC Tool reading) = KV
This for sure is also not 100% acurate becuase ERPM flactuates a bit, the voltage reading may be a bit of and the supply has to be stable but that’s what worked for me so far.
straight Kv calculation from the VESC tool terminal never worked for me but just spin it max erpm and in the lower left you see the value, then you have voltage, poles numbers and you calculate Kv. Super simple.
I could be wrong but I think the kV calculation in VESC tool only works in BLDC mode.
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Hope this answers your question 
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Thanks. I’ve seen numerous ways now.
i’m still wondering how/when the kv command in the terminal of vesc tool works.
and @Soflo’s comment made it sound like it was also just displayed in the normal vesc tool windows somewhere.
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It measures ERPMs. So I have 56k ERPMs and 47 V in.
So… 56,000 x .95 = 53,200 / 7 = 7,600 / 47 = 161.7 (170KV???)
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this is eggzakery how I do a sanity check on my motor(s) Kv!!!
In a pinch when I don’t have my optical tach I fully charge the drill and use the MFR rpm (yeah I know) or a drill press with a known RPM…
It’s been useful enough for me…!!!
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