One motor at 60amps or 2 at 30A?

Hi guys! :slight_smile:

I need help from someone with more experience!

I have a board atm with a single 6374 190kv TB motor on it. I’m running a 12S3P battery pack with 30Q cells.

I’m thinking of adding a second motor to it, but… Right now I have to limit my ESC at 60A from the battery as the pack can’t handle more current. If I add a second motor I will have to limit the ESC’s at 30A each. Right?

Do you think I will notice a difference or will it be the same apart from the added traction? I want some extra power for the steepest hills :sunglasses:

I know I should upgrade the battery pack also, but right now I’m on a tight budget as I’m studying for another year.

Thanks guys!

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The difference will be night and day.

@dareno I don’t need to say it, do I?:rofl:

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You will notice a difference going from one motor to two and yes you are correct in the assumption that you have to split the amp draw across both vescs.

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I was waiting for you just to make you feel good lol

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Old geezer fight, lol

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The diffrence is huge on a dual compared to single… HUGE!

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Not the OP, but I honestly can’t tell if all these answers are sarcastic or not lol

Thanks for all the replies! I can’t understand how the diffrence would be so dramatic with the same power tho’. But I will probably try it out and see :slight_smile:

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Best answer anyone gave ever. True builders spirit.

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Haha! Experience is knowledge :smile:

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Scientia est lux lucis

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For everyone who can’t speak Latin. :slight_smile:

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Slightly off topic question.

But would a for example 6374 motor ran on 40% load more efficient or a 5056 at 75% load

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The 6374 would be cooler at least :slight_smile:

It would probably also last longer since it has to do less work

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This. Lower temperatures also mean less power losses.

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https://www.electric-skateboard.builders/t/torque-curves-for-sk3s-6354-260kv-6374-149kv-6374-192kv/19721 <-- can see some efficiency charts here but agree with others in general more overhead is a good thing and keeping heat losses and amperage low is ideal.

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But you only split the “battery” current numbers, not the “motor” current numbers

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We were talking about the battery. Now share some knowledge about the difference using 2 motors and the advantages of motor amps. Share the love Brian. I love it when you go all techie

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First things first

Motor current ≠ Battery current

Right now you are using 60A on the motor and the battery

With two motors you will set 30A on each VESC but you can and should set 60A on each motor, this way you have 120A in the motor total, meaning you will have double the torque

Now to the catch, to limit the battery current to 30A, the VESC wont go above 50% duty cycle, what that means? In the hill that will require each motor to keep at 60A you will climb at half of your top speed for a given battery voltage

  • If you can’t climb some hill at 60A motor and battery, you will be able to climb it with dual motor

  • If you can climb a given hill right now, you won’t climb it faster by going dual motor

In the first case you would be torque limited, it doesn’t matter at what speed, your motor at 60A simply doesn’t have enough torque

In the second case you are power limited, and what constrains it is the battery max

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Dual motors will give you more stability on full acceleration, you will feel safer and might ride with more confidence, braking two wheels is way more effective than a full brake on one wheel. Acceleration will be more powerful as you are already increasing efficiency on motors by reducing the current and accumulating less heat.

Go for it and report back with your findings, thank us latter

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