1. #1
    I was wondering if anyone can help me with the current set resistors on my G540?
    From what i can gather they are used to limit current to the motor but there is also a 3.5A max per channel anyway.
    My x & y motors are rated at 3.5A. My z is rated at 4.3A so do i need to use a current set resistors or not? :confused:


  2. Hi Wayne,

    The instructions for the G540 doesn't say you can't have a resistor so I guess you do need one. They are set up for an output current of 1A per kohm of resistance, so I read it as you need a 3.5kohm (3.3k + 220R in series). The limit of 3.5A is the maximum safe working limit for the stepper driver, I suspect it will actually go a little higher than that and if you leave the resistor off it will default to some value just above 3.5A, however that may not be a safe operating mode.

  3. The G540 has idle current limiting which reduces the current at idle to 70% of whatever has been set via the resistor value.
    If there's no resistor, then current limiting is disabled.
    End result is that without current limiting, the motors will run hotter.

  4. #4
    Thanks Guys, I guess they are worth using then although its good to know there's no danger to motors / drivers until i get them sorted :tup:

Similar Threads

  1. TB6560 auto current reduction
    By Mjolinor in forum Motor Drivers & Controllers
    Replies: 1
    Last Post: 08-12-2011, 08:53 PM
  2. Current Set Resistors.
    By NzOldun in forum Motor Drivers & Controllers
    Replies: 1
    Last Post: 20-06-2011, 07:38 AM
  3. Simple Current Limiter (LM317)
    By Mad Professor in forum General Electronics
    Replies: 14
    Last Post: 13-07-2009, 09:01 PM


Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts