Welcome to Our Community

Some features disabled for guests. Register Today.

trying to help a friend

Discussion in 'Laser Cutters' started by Rustler85, May 7, 2019.

  1. Rustler85

    Rustler85 Well-Known
    Builder

    Joined:
    Apr 10, 2019
    Messages:
    15
    Likes Received:
    3
    good day my friend has a 60Watt tube laser cutter recently he has changed the tube and he has discovered that the negative wire has come undone on the opposing side... what i mean is that both wires are attached on the tube but on the other end the negative is just hanging connected to nothing....my question to help out my friend ... is this negative just a frame ground or does it need to go to the power supple to complete a circuit

    again a friend trying to help a friend :D im usually now in the cnc routers :D lol
     
  2. Rustler85

    Rustler85 Well-Known
    Builder

    Joined:
    Apr 10, 2019
    Messages:
    15
    Likes Received:
    3
    ***update***
    he has this no name power supply for the laser (looked all over the place for a wiring schematic) it has 3 slots on the left and 6 on the right for all the digital connections..... i am not sure if the laser connects to the supply to complete the circuit
     
  3. Peter Van Der Walt

    Peter Van Der Walt OpenBuilds Team
    Staff Member Moderator Resident Builder Project Maker Builder

    Joined:
    Mar 1, 2017
    Messages:
    1,400
    Likes Received:
    744
    the High Voltage return (negative) has to go to the Laser PSU. If it touches chassis gnd you can be electrocuted. Inside the PSU its not joined to GND but to the other end of the HV transformer
     
  4. Rustler85

    Rustler85 Well-Known
    Builder

    Joined:
    Apr 10, 2019
    Messages:
    15
    Likes Received:
    3
    ok... but it seems like all the ports on the left side where we would connect the into the PSU are occupied... i understand that on the right side with all the 6 ports there are for digital inputs and if you want to install limiters and so on... on that side nothing is mentioned for negative wire on the laser
     
  5. Peter Van Der Walt

    Peter Van Der Walt OpenBuilds Team
    Staff Member Moderator Resident Builder Project Maker Builder

    Joined:
    Mar 1, 2017
    Messages:
    1,400
    Likes Received:
    744
    Pictures would help but usually the return is on the back near the High Voltage output, usually soldered to the board. Have never seen it on the terminals at the front, but depends on which PSU it is. I know the good quality SDZ ones best
     
  6. Rustler85

    Rustler85 Well-Known
    Builder

    Joined:
    Apr 10, 2019
    Messages:
    15
    Likes Received:
    3
    buzz psu.jpg here is the look of his power supply loosewire.jpg here is the wire that is hanging out on its own... its soldered to the tube but has no home :(
     

    Attached Files:

  7. Peter Van Der Walt

    Peter Van Der Walt OpenBuilds Team
    Staff Member Moderator Resident Builder Project Maker Builder

    Joined:
    Mar 1, 2017
    Messages:
    1,400
    Likes Received:
    744
    Google around for pictures, and match
    I see some where the terminal on the left is a 4 pin. Yours is 4 pin on the board with a 3 pin plugged in?
     
  8. Rustler85

    Rustler85 Well-Known
    Builder

    Joined:
    Apr 10, 2019
    Messages:
    15
    Likes Received:
    3
    for my friend's laser that is what i am seeing and i saw the schematics for a 4 prong and it clearly identifies the 4th as a ground ... but if that is the case how did they connect it because it dont have a connector in place...
     
  9. Peter Van Der Walt

    Peter Van Der Walt OpenBuilds Team
    Staff Member Moderator Resident Builder Project Maker Builder

    Joined:
    Mar 1, 2017
    Messages:
    1,400
    Likes Received:
    744
    Thats the mystery I dont want to get involved in (lethal voltage, own risk and all that)

    Its not impossible that the same track has a pad in parallel on the board and it also exited on the back where the red HV cable comes out and was soldered onboard?

    If you open the PSU remember charged caps and multiple kilovolt inside! Dont die!
     
  10. Rustler85

    Rustler85 Well-Known
    Builder

    Joined:
    Apr 10, 2019
    Messages:
    15
    Likes Received:
    3
    well the laser has been down and disconnected for about 48 hours so hopefully its fully drained... i have linked this form to my friend hopefully he sees this before he works on it..
     

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice