VESC 6 MKVI HP - The VESC 6 on steroids

I’ve tested some by hooking the esc up to a CC/CV power supply to limit current then see how they spin up and change direction. That’s a safer way to do it incase something faults you aren’t sending several hundred amps from the battery into the esc. I ran an old vesc 4 up to 80k erpms recently, and while it ran fine at low motor amps, it would throw abs overcurrent faults at high motor amps.

So I guess I’d test that setup well on the bench then ride it with a shortened fault time and ease into it before I trust it.

A simple bench load tester can be made either by attaching a propeller (lots of cool calculators online) or hooking two motors together with a htd5 belt and shorting all the phases on the load motor.

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Pushing the ERPM that far depends on a lot of factors. Staying a good portion below 100K ERPMs has proven to work for outrunners in FOC while pushing the rated amps. 90K is a good value to stick to for our application.

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is the recommendation different for inrunners?

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Most inrunners have 4 or 6 poles, while the outrunners we use have 14, which means that for the same motor rpm, the ERPM will be more than doubled or tripled for the outrunner, which increases mosfet switching losses and eddy current losses. It makes inrunners much more efficient and reliable for high rpm applications.

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trampa was talking about erpm not rpm

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For a standard esk8 outrunner that has 14 poles, or 7 pole pairs, the formula is:

voltage * kv * pole pairs * duty cycle * efficiency = eRPMs
eRPMs / pole pairs = physical RPMs

12s 6380 outrunner 190kv motor:
50.4v * 190kv * 7 * 0.95 * 0.95 = 60k eRPMs give or take
or 8,500 RPMs

12s 56123 inrunner 230kv motor
50.4v * 230 * 3 * 0.95 * 0.95 = 31k eRPMs
or 10,500 RPMs.

VESCs don’t care about physical RPMs, only eRPMs because that’s when it’s activating that coil to attract / repel the magnet.

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I’ve seen geocities websites back in the day that were better than this. Navigating that website requires a PhD.

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it requires beer that’s what

or whatever alcohol you like, i prefer ciders out whatever

@jaykup
I went trough the numbers and… May I suggest the same KV for the purpose of the exemple?

12s 6380 outrunner 190kv motor:
50.4v x 190kv x 7 x 0.95 x 0.95 = 60.5k eRPMs give or take or 8,642 RPMs [60.5k divided by 7]

12s 56123 inrunner 190kv motor
50.4v x 190 x 3 x 0.95 x 0.95 = 25.9k eRPMs or 8642 RPMs [25.9k divided by 3]

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That’s a better apples to apples comparison for sure! I used 230kv as there is a set of those inrunners currently for sale on this forum so I thought the question might be related.

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