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Discussion Starter · #221 ·
Something I found out regarding "electric motors make all their torque at 0 RPM.

At 0 RPM you have no torque. Just a whining noise.

Roll into it at 100 RPM and you have all the torque.

This truck climbs everything so far!
 

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Something I found out regarding "electric motors make all their torque at 0 RPM.

At 0 RPM you have no torque. Just a whining noise.

Roll into it at 100 RPM and you have all the torque.
I don't know what's wrong with your controller, but that's not how motors work. After all, if they really had zero torque at zero speed you would never start moving, without giving it a push or rolling downhill.
 

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That was pretty tame in terms of incline, and it is a road, not unlike some farmers' lanes, so low gear seemed a bit dramatic and like an ICE move, lol. I suppose some mouse-powered ICE up ahead needs low and is holding everybody up to where they can't lug in high like you can.

You folks needed a good downpour on that road that day 😈

Am enjoying the cross section of roadcourses and the scenery. Came close to crashing my plane in the Utah canyons a few years ago....not many landing choices down there with a dead stick.

Good to see you not having any mechanical problems rearing their ugly head - not many options there for the others if you block the trail and it's no way to make friends or sell them on EV.

Are you monitoring temperatures? Would be interesting to see readouts as you start to work the machine.
 

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Ok not 0. But it's definitely not "all"
Okay, so what's limiting it? Without data there can be no rational explanation, but we don't know what motor current or anything else is doing. As a result, we don't know if current (and therefore torque) is being limited to protect a component, or perhaps just to make the launch from a standstill smooth for typical consumers driving their economy EVs.

Thanks for taking us along.

I don't think you're hearing the motor straining. The noise is all from gearing; the frequency is dependent on speed, and while the volume and quality of the sound does vary with load there's no audible indication of where the motor is in its operating range (of torque, current, temperature, etc).
 

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Discussion Starter · #230 ·
Okay, so what's limiting it? Without data there can be no rational explanation, but we don't know what motor current or anything else is doing. As a result, we don't know if current (and therefore torque) is being limited to protect a component, or perhaps just to make the launch from a standstill smooth for typical consumers driving their economy EVs.


Thanks for taking us along.

I don't think you're hearing the motor straining. The noise is all from gearing; the frequency is dependent on speed, and while the volume and quality of the sound does vary with load there's no audible indication of where the motor is in its operating range (of torque, current, temperature, etc).
"Cogging" or "stalling" is a common phenomena with brushless electric motors. It's well understood.

I will get more data eventually, I need to get Leafspy working for that data. For now you just have to enjoy the pictures and videos and be content with that :)

Gears straining/motor straining what's the difference? It indicates high load.

@remy_martian Utah sand is something else, very fine and lots of resistance to drive in compared to sand in other places. I still haven't posted the video from the toughest climbs yet, either.

I just got back home today, I'll probably post up a full breakdown of the trip and how the truck performed tomorrow. Let's just say I'm blown away with the performance off-road and nothing broke!

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Gears straining/motor straining what's the difference? It indicates high load.
"Straining" usually means "having difficulty due to excessive load"; if you're concerned about this it certainly matters which part is under strain, but if you're not concerned and just mean "working hard", then sure... the sound roughly suggests the load, without implying any problem.
 
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