Noob question thread! 2020_Summer

Magnets start to degrade at 80C.

Are you sure your temp readings are correct?

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I think I found the issue or one of them

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This is false information. Stop please

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I’m not spreading false information. I’m showing information that I’ve heard from multiple sources that answered various questions about outrunners. The one that was questionable was the one I was linked to since certain equations did not match up.

If there was a plausible info that is useful, allow me to know. Until then, I will see if I can find plausible info.

This is all you need to know about motor and vesc limits.

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thank you.

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This is false, it does not account for duty cycle. If your motor amps are set to 100A for example, you cannot even draw more than 95A from the battery, as the maximum duty cycle is set at 95%, and even that’s only at the exact top speed possible. If the motor is spinning at half its top speed, then battery amps cannot exceed 47.5A etc

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Motor amps =/= draws. I forgot to correct that statement since it was so late when I said that.

Edited.

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Right here you can see that the motor current is nearly double the battery current… just what was said above, you need to account for duty cycle.

At a low duty cycle, there might only be a 3 volts going to the motor, but something 60 amps going to the motor. That’s only 180 watts, and when divided by the battery voltage, let’s say 42 volts, comes out to around 4.28 amps from the battery…

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Interesting. I’ll probably be studying more on the equation so that I can see if I can understand this better. I’ve seen so many info on this that its hard to tell whats accurate. It looks like type of transformer. Would that be dependent on esc?

I like to increase my knowledge on this more.

Edit for the reason:

I still can’t find the kv rating on my dang motors lol

Also, how do i find the motor max? (Ironically, this was the start of my search of this whole thing lol)

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I think this is right… if I’m getting the idea.

The 44.4 is the max my motor can hold after doing the math. This is a 10s set up

Where did you get the 44.4 A number?

1600w/36v since my motors does not tell me max motor current.

Or would it be /42 since that’s max voltage in 10s?

I did both just incase.

Edit: I think I’m off on this…

I tried that. Imported the file in FreeCAD and tried to derive a drawing but that kinda didnt work because when you import the stl and make a solid out of it, it has a lot of weird triangles on non-flat surfaces and makes it impossible to get the measurements :confused:

You can’t find the amps without at least knowing the voltage the manufacturer assumed those 1600W.

Also motors take as much as you give them. If they run cold, they can take a few more amps. If they’re too hot to touch it’s too much. No complicated math needed

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800w² voltage used 36v 10s4p (32A) setup. But in my end, my motors gets extremely hot due to hills around my area. So I can’t tell for my part.

10S is 42.0V, not 36V

The ebike companies are all full of shit, to put it bluntly.

Get out a multimeter and check :crazy_face:

nominally its 36. I’ll try 42 though.

It’s not even 36 nominally, that’s the silliest part.

It’s closer to 37 than 36.

I think the 36 comes from “lead-acid equivalent” numbers or some horseshit like that.

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