Results 1 to 3 of 3

Thread: Power MIG 300 problem

  1. #1
    Join Date
    Oct 2020
    Posts
    2
    Post Thanks / Like

    Power MIG 300 problem

    I have two powermig 300 welders and I set one one up for FCAW to do a small project this week.
    It hadn't been used in about 5 years so I felt pretty happy when it turned on and ran with no issues other than an initial reset holding the settings switch on Startup. It ran for 3 days straight with no problems at all welding some light tubing for furniture frames.
    Thursday morning when I walked into the shop I turned on the machine, heard it come up, and the fan turn on briefly then turn off. When I was ready to weld I triggered the gun a couple of times and the fan came up so I squatted down to make an pass on a part and... nothing.

    I looked at the display and it was switching from dashed lines in the printouts back to the 120 17 setting I had it on, so I thought there was some sort of weird error and it cleared itself but when I tried to weld again screen went totally dark. Attempted resetting it several times and on two occasions got full LED lighting, all eights and all screens and all lights lit up which was really weird, and one time I only had two zeros in the left-hand window. Eventually it wouldn't respond at all. My other powermig 300 was diagnosed by a local dealer as having a bad motherboard so I didn't even go there. I was hoping to get a few more years use out of this good one. I've got 245 volts coming from the plug and there's voltage getting to the machine but but the machine only hums, the fan does not activate when you trigger the gun and of course nothing at all happens as far as the gun goes. It is totally blacked out with no LEDs visible. Any ideas?
    There are several red lights on the board but Im no guru so have no idea if they are normal.
    Any help would be appreciated.
    Finished the job with my 45 year old Lincoln 250 stick welder. Always there for me!

  2. #2
    Join Date
    Mar 2010
    Location
    Ceres, California
    Posts
    3,609
    Post Thanks / Like

    Re: Power MIG 300 problem

    These welders can be problematic when repairing. If the control pcb is bad, the digital power supply pcb should be replaced also unless it is the latest version.
    anything other than a G5632-2 power pcb must be replaced.
    The original pcb was a G3632-1. There are 2 LEDs on the power supply and a bunch of LEDs on the control pcb. Your problem with the half working welder sounds like the power supply is failing. So you can take a big chance and try the power supply from the other welder. You might get lucky. If it does work stop and put a new one in. The old G3632 pcbs are known to Kill the control pcb. so this might have happened to the other welder. since I recommend replacing both pcbs you can start with the power pcb and see if that fixes it. if it does your good. if not, the control pcb will have to be replaced also. The control pcbs in your machines most likely will not allow the software to be updated. The new software is not compatible with the older pcbs only current ones. The two pcbs together are almost $2000 us. Parts only.

  3. #3
    Join Date
    Oct 2020
    Posts
    2
    Post Thanks / Like

    Re: Power MIG 300 problem

    I appreciate the detailed information and your suggestion. I will attempt the power supply replacement from the other one and see if it works. No risk there for sure.
    Thank you very much for your help.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Page generated in 1,603,143,345.52038 seconds with 13 queries