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Connect terminal Ground to FG?


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  • Connect terminal Ground to FG?

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    Is it the correct way to be properly grounded? (would'nt want any shocks)

  • #2
    I've never seen a PS wired that way before, with the loop that is.


    • #3
      Me either.

      The FG is the Ground Input from mains and the two GND's are Ground output for distribution. All of the arcade power supplies I've wired in use FG for mains ground and then take your pick on GND for the jamma harness etc.

      Hopefully someone more experienced can comfirm but I would NOT be plugging that into anything in its current state until an expert comes along and comments.

      My Projects - Space Invaders Bartop, Williams A-Go-Go, Galaxian Bartop, Jukebox Kiosk 1&2, Jukebox Kiosk 3, Virtual Minipin, Generic Upright, MultiCab, Rampage,


      • #4
        That's not correct.

        You'd probably find the PSU is internally grounded between DC ground and Earth, via a filtering capacitor, meaning it won't show continuity on a multimeter.
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        • #5
          actually i found that pic on the ukvac forum, i wanted to know about earths and grounds.
          anyway below is my psu
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          did a little bit more searching found below is more what I'm on about pic from wiki.aussiearcade is this they way the earths and grounds be linked? and should i do this to my psu?
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          Attached Files


          • #6
            There is no problem wiring FG to ground,its been done like this since the 80s,common practice for LAI wired cabinets.
            If you notice on the screen any slight interferance you will probably find this jumper has been disconnected.
            I have wired many different branded power supplys like this and never ever had a problem.
            Its a good little trick to try on the cheap asian cocktails that have been flooding the market over the last 10yrs as it can improve picture quality.


            • #7
              Yep had to do this plenty of times to get rid of interference in the screen (as GIBO stated) Daytona USA seems to develops this issue over time and jumping the grounds usually fixes it.
              Is this the 5 o'clock free crack give away?


              • #8
                Some power supplys have FG connected internally but this isn't that common. They are mainly separate so you can wire the grounds as you may need such as when an isolation transformer is in the machine or a chassis that must be left un-grounded etc. Atari machines don't always ground the chassis for some reason but there are other brands as well. Anything with a setdown tranny inside I would be checking on the diagram.

                Always run a ground from FG up to the header panel fluro lighting if for some reason you can't connect FG to the common grounds. A lot of people have got a belt out of a simple fluro assembly when the ballast dies.


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