AWG Wire infromation

Hi all, have 2 D6374 - 150KV motors on back order, and need some understanding on wire to purchase for each motor.

Will be running these motors on 48Vdc @ up to 1000Watt, the connection to each motor is less than a meter in length for PSU to motor cable.

Can someone please provide some direction.

Regards Jerry

I use 10AWG with silicone insulation for my SK3 6374’s and it’s overkill. I’m sure I could run 12AWG and be fine.

Generally in these situations you reference an “ampacity chart”, as the current through the conductor is the driving factor of how beefy it needs to be. Voltage is generally limited by the insulator. e.g. here’s some 22AWG hook up wire rated to 5,000 volts - but it wouldn’t handle any more than 3 amps.

Your requirements of 48V and 1KW boils down to a 20.83A required rating (1000 / 48 = 20.83). Aside from conductor size (strand size, count and bundling really) and material (copper > aluminum), the other factor is how hot it is allowed to get which is limited by the insulation and where the wire is going pass physically.

I would go with stranded 10 or 12 AWG with silicone insulation. Nice and flexible, still well within soldering territory, can get very hot if it needs to, and would handle your 1KW load at 100% duty without uncomfortable/painful heating of the conductor if you put your hand down on it.

I usually go with this product when I’m wiring a new motor https://www.amazon.com/gp/product/B0756TDTDM

edit: I wouldn’t worry about voltage drop or anything like that for such a short run. You’re gravy.

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Hi metanoic, thank you for the very helpful and precise information, it is really appreciated.

I am new to all this, and any advice to clear things up will make it easier to handle.

Kind Regards Jerry. :man_student:

Thanks! I am using 10 AWG wire but it is quite hard to prototype since they don’t fit into the odrive very well. Do you have any advice on what connector to use or are you soldering the cables onto the odrive directly?

Personally, I love the “Amass MT60” connectors for motors. They will just about accept 10AWG wire, if you have a good soldering iron (I use a Metcal SP200 with a 5mm chisel tip), and I have driven them at 100A without them getting too warm.

The wire itself I solder directly to the pads on the ODrive. I don’t use the screw terminals.
But for smaller motors up to 30A, there’s the MT30 which will accept up to 14AWG.

Don’t forget wire length. A wire is a resistor so current times resistance gives you the heat it will generate. You can find charts that give wire resistances per length units.

Very important if you intend to use longer cabling.