Page 2 of 2 FirstFirst 12
  1. #11
    Quote Originally Posted by cropwell View Post
    If you are using GRBL v0.9 then D11 should put out a 0-5v analogue signal
    https://github.com/grbl/grbl/wiki/Connecting-Grbl. I have the feeling that describing D11 output as PWM is in error.
    No. The MEGA328/2560 based arduinos do not have a DAC, or any other form of analogue output. They provide a number of PWM-enabled discrete outputs (those prefixed with a tilde on the board silk-screening) with the signal value switched between GND and VCC - which if used for e.g. LED drives allows a direct control over the LED luminance, similarly for a DC motor drive; but the output remains a digital PWM signal (they do, however, support multiple ADC inputs)
    Last edited by Doddy; 30-05-2018 at 06:39 PM.

  2. #12
    Quote Originally Posted by Doddy View Post
    No. The MEGA328/2560 based arduinos do not have a DAC, or any other form of analogue output. They provide a number of PWM-enabled discrete outputs (those prefixed with a tilde on the board silk-screening) with the signal value switched between GND and VCC - which if used for e.g. LED drives allows a direct control over the LED luminance, similarly for a DC motor drive; but the output remains a digital PWM signal (they do, however, support multiple ADC inputs)
    You are right Doddy, I have had a closer look at the AnalogueWrite function. The DAC converters in the arduino put out a variable duty cycle PWM 0-5v. I have a feeling that that is where the OP's problem lies. I fell into the trap of assuming that, when Arduino described the board as having DAC function they meant in in the true sense. Maybe a simple RC integrator would prove the root of the problem, but in the long term an OpAmp circuit would be better (to give a better 0-5v). I am surprised that the inverter does not have an integrator on the input VI.
    Last edited by cropwell; 30-05-2018 at 07:14 PM.
    Albert Einstein may have been a genius, but his brother Frank, was a monster

    Having just moved to Windows 10 (which is crap) My stress levels are through the roof !!!

  3. #13
    Quote Originally Posted by Doddy View Post

    Eh?, I'm a little confused - I'm assuming that you have an adequately earthed connection to the machine?, my next thoughts would be how the supply earth is exported to the garage - whether through a 3-core cable or a local earth rod... but you're clear that the trip also occurred in the house and that the RCD circuit is okay, so I won't pursue that.

    What do you mean by grounding the machine earth through an additional PSU - currently laptop power - I'm not aware of a laptop PSU that exports an earth - I'm guessing from the language that you've connected the negative supply to the machine earth??, if that's the case then that isn't earthing the machine and this could be a cause of your problem. Absolutely provide a low-impedance earth strap from the machine to the garage supply earth. Also - from your picture of the machine - make sure that all exposed metalwork has a reliable earthing.
    Well the machine and all the machines metal parts are earthed so the spindle, power supplies for the drivers etc all go to earth - being in the UK almost everything here is earthed. In my garage this comes through 3 core cable. The spindle has also been earthed by myself and this runs through the spindle cable.

    However the electronics box/machine case, ardunio, relay are not earthed... I can work out the machine case but I'm not sure how you earth a arduino board?

    Also the board I'm using is running grbl 1.1
    Last edited by Mr*Beaver; 30-05-2018 at 07:16 PM.

Page 2 of 2 FirstFirst 12

Similar Threads

  1. Fanuc OT - Fuses blowing
    By Cube3 in forum Machine Control Software
    Replies: 7
    Last Post: 19-07-2017, 07:03 PM
  2. HEIDENHAIN VRZ 731B - Blowing Fuses
    By goweruser in forum General Electronics
    Replies: 2
    Last Post: 06-02-2017, 09:52 PM
  3. Wabeco controller fuse blowing
    By Stewart in forum Motor Drivers & Controllers
    Replies: 3
    Last Post: 01-03-2015, 09:37 PM
  4. So close.....am882 driver blowing fuse
    By Danielroyal25 in forum Motor Drivers & Controllers
    Replies: 12
    Last Post: 29-03-2014, 08:32 PM
  5. 3 axis driver...Fuses keep blowing
    By dudz in forum Motor Drivers & Controllers
    Replies: 5
    Last Post: 28-01-2013, 07:05 PM

Bookmarks

Posting Permissions

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