Increasing range by unplugging motor

Hey guys i built my board so i can upgrade to dual motors when i move out to San Francisco.

If i deiced to unplugged the phase wires so only one motor is running to decrease power consumption and increase range would that be harmful to my second vesc as it would ask for power but not send it anywhere right?

I have considered doing this as well. I would remove the drive belt @LordChaos to reduce resistance too, assuming you have a satellite setup.

I’m always a bit reluctant to do this out of a fear of frying a Vesc.

Has anyone, (maybe an EE) got a wiring diagram available to indicate where a switch might be located on a circuit to allow this?

Proven that 2 motors are actually more efficient than 1 because one motor will pull more amps under stress than 2 will.

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It shouldn’t be harmful at all. However, Do nOt let the phase wires touch while riding!

You’ll end up flat on the ground. The VESC will provide power to the motor phase leads, but since there is nothing connected, it won’t draw anything. You could also just unplug that VESC from the internal power if you wanted to be super sure. But if you’re thinking that it will like blow up because there’s no where for the power to go, that will not happen :slight_smile:

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I second this, I didn’t really notice any difference in range once I upgraded, due to how much more distributed the load is.

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Would be the same with horses pulling a wagon. One horse wont go as far as 6

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oh that is great! i was basing the decreased range from the Eskate range calculator which say 2 motors use more watts per mile

Yes but say you only had one bale of hay. How long could you feed that team of 6 horses? Might make it farther feeding just the one horse and pulling your wagon slower

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6 horses burn less calories per mile than one towing you and your bail of hay.

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Is that always true though? One big motor is more efficient than two smaller motors. If you look at the torque curves, motors have pretty poor efficiency under low loading

I’ve never had a dual-drive, but my SK3-6374 single-drive averages 12 Wh/mi. I’ve recorded a peak efficiency of 8 Wh/mi while also traveling at 20-25 mph. The typical average is 16 Wh/mi

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Are you using the hm-10 and ackamaniacs app? Mine averages out to 12wh/mi for dual vesc dual 6355 190kv on 12S

True. But 2 small motors is still more efficient than one small motor. (apples don’t taste like oranges, but may smell like oranges if left in the same bag?) C’mon man…

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What he’s saying is that he agrees with you- for higher loads, two motors better than one. Conversely at low loads one motor is better For long range, what do you want to be at, low loads low speed or multiple motors at a higher speed (peak efficiency on the power band)

Only problem with that is wind force (basically dominating your losses) increases with the square of velocity so you really need to go low and slow for a max range and then one motor works better

Better way to put it: you will gain efficiency with multiple motors as you go faster. But for each mph the wind force will eat your efficiency gains several times over :slight_smile:

Just want to confirm this. 1 of my belt on my BoostedBoardV2D+ broke, and ordered some replacement belt. But I still wanna use the BoostedBoard. While waiting for the replacement, I disconnected the motor without belt. I say it increases my range significantly. I just remember cause Boosted used to have a single drive.

current u need to produce forward momentum can be halved between two motors and since the copper losses are current squared times resistance any reduction in either current or resistance is a boon and the losses will be decreased. Generally to decrease this dominating loss you want MORE motor.
The only reason you’d be more efficient with less motor would be if ur motor or motors were too big to begin with and your main inefficiency therefore would be iron losses. This is the generally accepted guideline for motor sizing and efficiency

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Thanks for all the replies it great to see all the feedback, Knowing this now i wish i have go to dual motors sooner stoked to see the lift off power when i rock dual 6374s

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Does anyone know what the diameter of the Turnigy 6374 stator is?

that should be a 8mm and mentioned in the specs

8mm is the shaft, a stator is something different:p i have one laying around at home, i will measure it tonight.

Thank you! Can you get me the diameter and length please?