Free 173 Best Homemade Tools eBook:  
Remove advertisements
Page 1 of 2 1 2 LastLast
Results 1 to 10 of 18

Thread: Replacing capacitors in old TIG welder, and adding cooling unit.

  1. #1
    chy_farm's Avatar
    Join Date
    Apr 2018
    Location
    Yokohama, Japan
    Posts
    57
    Thanks
    31
    Thanked 105 Times in 29 Posts

    chy_farm's Tools

    Replacing capacitors in old TIG welder, and adding cooling unit.

    Good morning gents,

    I got an old but refurbished TIG welder last summer, but after giving her some inspection I found she needs some of her capacitors replaced with new ones. The seller/dealer said she got a lot of cleaning inside, seems it's true, but yet some hard-working parts are showing some signs of deterioration. It was fortunate to me that I was able to bumped into an engineer who has been working at a local welding school(may be it is operated local government officially). What he said was all very accurate in detail about the electrical functions of this machine, and the way he told was generous and gentle. So gradually some doubtfulness in my mind faded off, and got inclined to put trusts on his words.

    He said in the early models of this set-up, he encountered several cases of issues on a set of capacitors on the very limited area of the circuit board, the power supply board.
    Replacing capacitors in old TIG welder, and adding cooling unit.-capacitors_mb_board_05_s.jpg
    Capacitors_MB_board_05_s.JPG

    Area with red marking in above, and the said capacitors are the larger round stuffs with red arrows. He said these capacitors tend to get a lot of electrical stress when we use the welder in excessive duration of time with higher amperage, while others around them are not like that. Actually he showed me some data he has got when he has made examination on other capacitors, that tells the other stuffs have been working all right on this model.

    Replacing capacitors in old TIG welder, and adding cooling unit.-capacitors_mb_board_00.jpg
    Capacitors_MB_board_00.JPG

    When I saw the top surface where you see the 'Y' marking above, these marking show no sign of distortion. (Incidentally in some bad cases this Y mark shows some rise upward, tells this part gets pressure inside. )

    So I told him this fact, but he replied that still there is some possibility of deterioration in the capacitor which causes oxidation to the brazing area of the board.
    So this words of his led me to the next attempt to remove these capacitors as below,
    Replacing capacitors in old TIG welder, and adding cooling unit.-capacitors_mb_board_03_s.jpg
    Capacitors_MB_board_03_s.JPG

    and see how the colors of the 'land'.(they call the small holes with copper plating on any circuit board 'lands/land')
    These lands, especially where I marked with red arrows has got some dirt around them.
    Replacing capacitors in old TIG welder, and adding cooling unit.-capacitors_mb_board_01_2.jpg
    Capacitors_MB_board_01_2.JPG

    In the worst case, if we keep these untouched, these oxidation go farther deeper to the copper plating of the board, and finally invite disconnection to the part. Yet an examiner/user may not be able to find out where to be repaired, since the issue is undermined at the foot of the capacitors which looks pretty good at glance!
    Replacing capacitors in old TIG welder, and adding cooling unit.-capacitors_mb_board_06.jpg
    Capacitors_MB_board_06_s.JPG

    Could you guys tell what are the new capacitors I replaced, they are all a tad smaller than the old. Small but has better durability to the load, the old bears 85 degrees Celsius, new 105 degrees.

    to be continued...

    Chy

  2. The Following 6 Users Say Thank You to chy_farm For This Useful Post:

    basil3w (04-12-2018), blkadder (04-13-2018), PJs (04-13-2018), rlm98253 (04-12-2018), Seedtick (04-12-2018), tonyfoale (04-13-2018)

  3. #2
    chy_farm's Avatar
    Join Date
    Apr 2018
    Location
    Yokohama, Japan
    Posts
    57
    Thanks
    31
    Thanked 105 Times in 29 Posts

    chy_farm's Tools
    I also made a check to the secondary power board of this welder, found some minor deterioration to the capacitors and resistors located near IGBT(Insulated Gate Bipolar Transistor) s.

    Resistors:
    Replacing capacitors in old TIG welder, and adding cooling unit.-.jpg
    reverse side looks like this, had some burn under these resistors.
    Replacing capacitors in old TIG welder, and adding cooling unit.-.jpg

    This part seemed to be the worst, some sticky stuff had accumulated a lot of dust.
    Replacing capacitors in old TIG welder, and adding cooling unit.-.jpg

    Replacing capacitors in old TIG welder, and adding cooling unit.-.jpg

    Capacitors:
    Four bigger capacitors were removed and checked the holes;
    Replacing capacitors in old TIG welder, and adding cooling unit.-cimg1935.jpg

    Replacing capacitors in old TIG welder, and adding cooling unit.-cimg1937.jpg

    (to be continued...)
    Chy

  4. The Following 2 Users Say Thank You to chy_farm For This Useful Post:

    blkadder (04-13-2018), PJs (04-13-2018)

  5. #3
    chy_farm's Avatar
    Join Date
    Apr 2018
    Location
    Yokohama, Japan
    Posts
    57
    Thanks
    31
    Thanked 105 Times in 29 Posts

    chy_farm's Tools
    I replace 6 of these original resistors that has been deteriorated with excessive heat, with cement resistors having larger capacity. Old ones were 3 watts, new ones are 10 watts, marked with red arrows here;
    Replacing capacitors in old TIG welder, and adding cooling unit.-2nd_inverter_drive_06_mod.jpg

    Amongst them two in the middle are capped with 'black hats', arrows show them;
    Replacing capacitors in old TIG welder, and adding cooling unit.-2nd_inverter_drive_08_mod.jpg
    This black hats are made of a new material invented at a domestic maker here, which has high heat conductivity useful when we need more heat radiation to electric parts.

    This area has been the most heat concentrated area, so made an aluminium heat sink and added here.
    Replacing capacitors in old TIG welder, and adding cooling unit.-2nd_inverter_drive_10_mod.jpg

    After these replacement I tried adding a couple of cooling funs to this area.

    (to be continued...)

  6. The Following User Says Thank You to chy_farm For This Useful Post:

    PJs (04-13-2018)

  7. #4
    chy_farm's Avatar
    Join Date
    Apr 2018
    Location
    Yokohama, Japan
    Posts
    57
    Thanks
    31
    Thanked 105 Times in 29 Posts

    chy_farm's Tools
    The inverter boards to which I gave some replacements are on the second deck in this TIG welder, posting a pic showing its back side;
    Replacing capacitors in old TIG welder, and adding cooling unit.-fans_addition_00.jpg
    As this pic tells the second deck has a little room to the ceiling, and what's so worse there was not window on this deck.

    These are what I added to it!
    Replacing capacitors in old TIG welder, and adding cooling unit.-fans_addition_01.jpg
    After these repair this welder does not get over heated at all.

    Hope it can be of some help to your welder!

    Chy

  8. The Following 5 Users Say Thank You to chy_farm For This Useful Post:

    blkadder (04-13-2018), bvd1940 (04-12-2018), mwmkravchenko (04-12-2018), PJs (04-13-2018), Priemsy (04-12-2018)

  9. #5

    Join Date
    Apr 2014
    Posts
    15
    Thanks
    0
    Thanked 10 Times in 3 Posts

    Gadgeteer's Tools
    Well done! I've, also, brought TVs and VCRs back to life by replacing bad caps. Most of the time the caps were identified, due to leaking and swelling.

  10. The Following User Says Thank You to Gadgeteer For This Useful Post:

    PJs (04-13-2018)

  11. #6
    bruce.desertrat's Avatar
    Join Date
    Nov 2017
    Posts
    113
    Thanks
    67
    Thanked 121 Times in 57 Posts

    bruce.desertrat's Tools
    Ugh. The Capacitor Plague plagues us all. Nice fix on that welder!

  12. The Following User Says Thank You to bruce.desertrat For This Useful Post:

    PJs (04-13-2018)

  13. #7
    Jerry4Truth's Avatar
    Join Date
    Feb 2016
    Posts
    11
    Thanks
    1
    Thanked 2 Times in 2 Posts
    Thank you chy-farm, that is some very useful information. Some I am sure to use in the future.

    Jerry4Truth

  14. #8
    chy_farm's Avatar
    Join Date
    Apr 2018
    Location
    Yokohama, Japan
    Posts
    57
    Thanks
    31
    Thanked 105 Times in 29 Posts

    chy_farm's Tools
    Quote Originally Posted by Gadgeteer View Post
    Well done! I've, also, brought TVs and VCRs back to life by replacing bad caps. Most of the time the caps were identified, due to leaking and swelling.
    Good afternoon Gadgeteer, thank you. Glad to know you know much about the same sort of things. Wish to learn some more from you too,
    Chy

  15. #9
    chy_farm's Avatar
    Join Date
    Apr 2018
    Location
    Yokohama, Japan
    Posts
    57
    Thanks
    31
    Thanked 105 Times in 29 Posts

    chy_farm's Tools
    Quote Originally Posted by bruce.desertrat View Post
    Ugh. The Capacitor Plague plagues us all. Nice fix on that welder!
    Hello Bruce.desertrat, yes they sometimes do bad on boards, let's keep watching them! Thank you for your comment.
    Chy

  16. #10
    chy_farm's Avatar
    Join Date
    Apr 2018
    Location
    Yokohama, Japan
    Posts
    57
    Thanks
    31
    Thanked 105 Times in 29 Posts

    chy_farm's Tools
    Quote Originally Posted by Jerry4Truth View Post
    Thank you chy-farm, that is some very useful information. Some I am sure to use in the future.
    Jerry4Truth
    Hello Jerry4Truth, and good afternoon Sir. I love to see your avatar image here! Is this telling that you are one of the veterans? If so, I always pay greatest respects to them.
    Thank you for your comment on this capacitor issues, but I really do not hope you got troubled with that sort of capacitor things in any machines there, lol.
    Chy

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Tags for this Thread

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
  •