Power supply for 4 ODrive Robotics D5065 - 270kv?

Hello,

I want to use 4 odrive motors to build a 3D printer.
I used the core xy principle, which means two motors are on the x and y axes and one on the z axis and one on the extruder.
My question is, if I take the ODrive Robotics D5065 - 270kv motors, how much Amper will need my power supply? My max speed is only 200 mm / s means I do not need the complete power from the engines.

Thanks for your help
Tim

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If I had to take a guess the motors would not draw more than 10 amps at the speed of a 3d printer. That does not include the rest of the electronics of course. It also depends on the voltage you are running this at. If you had the voltage you would like the estimate would get better. You always want to have more than less in this case for the powersupply current capability

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To find out how much current you max in each motor you can use the odrive motor guide. Create a copy ('cause you can’t edit the original) enter your machine parameters at the bottom (pulley circumference, load mass, and bus voltage are the most important here) and then go to the motor’s “max current” column and keep lowering that until the motor no longer meets your benchmark for acceleration. Keep in mind that this isn’t perfectly accurate due to the fact that it won’t account for frictional losses or the weird kinematics of a CoreXY frame, but it should give you a good benchmark for what you need. Also keep in mind that exceeding the max current your power supply can provide will cause a sudden loss of torque, which might cause issues.
I feel like I also should state that the ODrive D5065 motors are probably overkill for you application. I’m building a CoreXY laser cutter and I’m using two Turningy SK 3536-1400 for my A and B motors and it looks like this (for refrence the machine frame is 75 cm wide and 50 cm deep). The motors I’m using have around a quarter of the power of the D5065 motors you named. Obviously this statement about overkill goes doubly for your extruder motor and possibly your Z motor as well.
If you have questions about some of the other design choices that I have made, or would like to know what components I’m using, feel free to send me a DM.

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Calculate it based on power. In practice, the most power you can pull from an odrive is what your house supports. 1500 watts in the US (110V / 15A), or about 3500 watts in Europe (220 / 16A).

Calculate the max torque and speed you need from the motor - that gives you max power per motor. Then you pick a power supply based on the power rating.

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I have 2 server power supplies in series.
1200W each at 12V. Work great. If you only need 12V take one of those. Found mine for 28€ on eBay, 28€ for both

5065 is really overkill for 3d printers since it doesn’t really require much torque at all. I suggest you pick smaller motors. Powerwise you’ll do fine with 500-1kw PSU as you don’t need much torque at all.