2

I am learning to do electronics making a things like a 3d scanner and a CNC. I want to make my own board to control the steppers and I have got the stepper drives, prefboard, arduino, etc. The only part I am struggling on is the wire.

5 stepper - 1.5a pre phase and dc 3.6v

Power supply - 12v 3a.

I have been looking around and its looking like I need 18awg to 22awg but not too sure, getting a little confused and maybe overthinking it. The wire will only be used for very short distance on Prefboard when I dont want to solder.

Stephen Mottershead
  • 25
  • 3

2 Answers2

3

The ampacity is the current carrying capability of a wire. In other words, how many amps can it transmit?

You may have to check these parameters: Maximum amps for chassis wiring and Maximum amps for power transmission.

So you have to use AWG 27 at least.

The wider the cable, the better.

Reference: https://www.powerstream.com/Wire_Size.htm

Manalizer Pro
  • 41
  • 2
2

The main issue you have to worry about is voltage drop (and hence power drop) across the cable itself when you want to output full power to the motor. The resistance drop of a wire is linearly proportional to length of the wire. Also the thicker the wire, the less the drop. Never a bad idea to go for thicker wire in case you want to longer cables to your motor.

nabulator
  • 648
  • 1
  • 7
  • 20
  • It would appear the motors are being run with a higher voltage from a chopping driver, so the voltage drop in the leads will probably be compensated out by the same current model regulation that handles the winding inductance. – Chris Stratton Nov 28 '20 at 21:44
  • Yes, you will usually get too large of a voltage drop long before the wire overheats. Wire tables are based on wire heating. – Mattman944 Nov 29 '20 at 00:53
  • thank you for the help :) – Stephen Mottershead Nov 29 '20 at 15:53