MAD Fury. MAD hubs Direct Drive conversion

Sorry I just have hearsay on it, no specific knowledge on diagnosis. I read Damon’s article, seems solid.

Maybe just fire into it ::slight_smile:

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I will check for shorts but the only ones you can detect with a multimeter are between motor wires and motor shaft/can. Then you can check connections between phase wires. You can not detect shorts inside the windings. The motors are new and I prepared a lot of them for the GB and they spin as the others, but you never know. It seemed really weird to me too that only after 3km one vesc blew up since I used same vescs and battery with the previous motors for 1 month at least. I thought could be because of the antisparks and the facts that these motors ask more current compare the previous one.

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U can use an LC meter to check the windings. Like 15$

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I may have it at work. I will ask

Have to check the L with rotor off

I will read about it and aks to the guy here because I am not an epert in how to interpret these values

Super easy just check all three phases and they should have inductance values within a couple hairs.

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so one pin on the motor phase wire and the other on another phase wire and the inductance has to be almost 0?

Inductance will vary by how many turns of wire around the teeth. If it’s shorted the number will be less. I forget the number it shows when I check all the phases but it’s like 600 mili henries maybe or whatever denomination. U can see if shorted to the stator too. Which although not ideal will still be ok.

It’s a cool tool for 15$

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Like hummie says, inductance should be roughly the same between each phase. loop of wire = inductance, Many loops of wire = more inductance. i.e if it is cut of somwhere along the way, less inductance will be shown.

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its an awesome tool giving very exact results when you alter your physical circuit. Core in or out…big or small loops… w magnets nearby? A tool registering the invisible maybe isn’t rare but throw in magnetism and cool colored buttons and only 15$ You know Im off work and should be making last owed motors when I’m really excited to talk about the LC meter.

do you have a link to the one you use?

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ah ok perfect. I found it also locally so I will get it faster. Thanks!

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Using it today ive come across a question maybe @linsus you have an answer or I know there’s other electronics people here too

I get the same inductance on each of the 3 phases within maybe 5 mili henrys for all the motors, you can see 285, and you can see measuring to just the wye, which is halfway, and it’s always less by 20. Why consistently is it less measuring halfway?image image image

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Your question is why you have half the value in a Star connection when meassuring between middle point and a phase? Well. Theres less turns half way thru.

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Between phases theres always gonna be roughly the same given a symmetrical motor. Between any given phase and middle you’d have rougly half. With some offset. Simply cause when meassuring the device uses current. And the current will only flow thru the coil between your probes. i.e probing 1 and middle will only meassure inductance of the blue coil, while point 1 to 2 will meassure the inductance thru red and blue coil. Not sure what the accuracy for your LC meter is but seems about right.

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That meter has been a staple in checking inductance. Great little tool!

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Can recommend this one, have it at my desk at work. 7$ and it does a load of things, dont have to select any mode, it just detects w/e you put in there. It even tells if you’re putting in a MOSFET or a Bipolar Transistor. Which is quite facinating for the small number of components.

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So for the moment tested with a multi meter shorts along the motor phase wires and everything looks fine. I will tomorrow if I find a LC meter and meanwhile order one.

I mean I get less than half the inductance when measuring from the star to end of any phase. 126 is not half 285. Measuring a complete phase and not just to the wye/star I’d have thought would be double