Beginner Question Thread! 2023 Edition

It’s milliohms, not megaohms. But yeah, the sensorless motor looks a bit high for that. What motors are they? Are they both the same make and model?

Are the solder joints good and the connectors to the ESC solid?

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Can you measure the resistance of each phase manually, to see if one is out of whack? The fact that the inductance is also off the mark seems weird.

Yes, both are bkb 6354s, but honestly beat up pretty bad… The windings were filthy and not much better after my spray can of air tried to clean it. But now thar I think about it, I actually didn’t cut down the phase wire to expose new wire to solder to the connector… Which I did do on the second motor… I’ll try that tonight.

Oh man, I know I’ve done this before, but I’d have to figure it again… What am I looking for?

You’re looking for all of the phase resistances to be equal. If there’s a small short or otherwise altered connection somewhere i feel like that might explain why the inductance changed.

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You can also try a BLDC hand test and if anything is off, there are other things listed there to go more in depth

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Things got worse after I clipped the old connection and soldered on fresh wire into the connector… :sob: I appreciate the help but these motors were free, trash from the start… I was hoping to use them both on a trike build later this summer, but oh well…

Switch which side the motors are connected it, and see if the odd readings switch sides.

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Anyone ever get this error:
image

Trying to get RT data on the desktop tool, but I hit that.

I’m about to order a davega x, and I was wondering the difference between the 7 and 8 pin connector?
image

My guess is how many pins your JST communications connector has on your VESC. Some have 7, some have 8.

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You can put a 7 pin connector in an 8 pin socket (make sure you align it to the correct side)

Or you can chop down an 8 pin connector to fit a 7 pin socket.

If you’re unsure how many UART pins your esc has, you can make either work, not a big deal

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You’re right, I had them connected wrong. Resoldering the connector didn’t seem to help. The windings were filthy and look a little loose in spots, so I’m assuming that’s the issue. I’m fine with them at this point though… They’re going back on the shelf for a trike build later this year.

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Hello
Imot truck looks wierd, dosent motice before today.
I wil tale some picture.
What can i do?



Get a new one, that shit looks warped beyond repair

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I feel dumb for needing to ask but can I run sHFI on an OG focbox single at 12s?

I think shifi needs the phase filters to work properly and I don’t know if v4 had that

It seems like I’m not the first to ask but I can’t seem to find a clear answer on this, how would one go about figuring out belt length with idlers? Is there a formula?
I imagine I’m not the first person to run boardnamics XL precision mounts (100mm c2c ±10mm), dual 636 bearing (6x22x7mm) idlers, and 15/72 gearing, can anybody say from experience what size belts work?

Guess. If your guess is wrong, chop it up and

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Unfortunately there’s no easy formula. If you already have a belt, you can use Brian’s method^^.

You can get an approximation by using string or maybe a thin strip of cardboard (you want a bit of thickness, so paper is less preferable) wrapped around the pulleys and idlers, but it won’t be perfect - might be off a tooth or two.

You can spend a bunch of time and effort in CAD drawing up your pulley arrangement and calculate the path length that way, I’ve done that once or twice.

Or you can take a guess and buy like eight sizes of belts, and pick the one that fits best. Also done that once or twice.