Snap-On 110V YA219 Mig Welder Diode Question
RSS | Subscribe | Contact Us | Advertise | About Us
Results 1 to 5 of 5
  1. #1
    Join Date
    May 2018
    Posts
    10

    Snap-On 110V YA219 Mig Welder Diode Question

    First I'd like to say I'm new to the forum and thanks in advance and I appreciate any input. My question is how the diode/rectifier set up in my welder works.
    I have had this welder for probably 30 years now and it has always worked pretty good however it recently quit working. While I was welding the other day it began buzzing loudly and threw the breaker in the service panel. I have no electrical experience but not wanting to buy another machine and there are no electric repair shops in my area I decided I had better try to fix this myself.
    After removing the side covers and checking connections etc I began checking diodes because I have heard before that diodes are a common problem with 110V mig welders. There are only two diodes mounted to the heat sink on the power unit and after removing them I found that the diode on the left side (ground side) is shorted and has no resistance either way I check it and the diode on the right side (gun/wire side) appears to be working correctly and only flows one way and not the other. Both of the existing diodes appear to be 70A 300v standard stud mount diodes and I have ordered two new standard 85A 1000v stud mount diodes from Allied Electronics. Hopefully this will take care of the problem!
    I have no idea how this machine even works so my question to you folks is:
    Every thing i have been reading about rectifier bridges is that they use 4 or more diodes, half standard and half reversed. This machine only has 2 and they are both standard and have the same part numbers. So how does this set up work. I have attached a picture of the set up.
    Attached Images Attached Images   

  2. #2
    Join Date
    May 2009
    Location
    Wyoming US
    Posts
    3,183

    Re: Snap-On 110V YA219 Mig Welder Diode Question

    Most welders use a bridge diode setup, with four diodes.
    If you have a center tapped transformer, you only need two diodes.

  3. #3
    Join Date
    Sep 2008
    Posts
    177

    Re: Snap-On 110V YA219 Mig Welder Diode Question

    When there are 4 diodes used-that is a full wave bridge rectifier- and you get smoother DC and don't need a center tapped transformer- when only two diodes are used that is a Full wave rectifier but you need a center tapped transformer-
    Here's a link that will explain it fully

    https://www.electronics-tutorials.ws/diode/diode_6.html
    Last edited by 131re; 05-17-2018 at 07:49 PM.

  4. #4
    Join Date
    May 2018
    Posts
    10

    Re: Snap-On 110V YA219 Mig Welder Diode Question

    Quote Originally Posted by 131re View Post
    When there are 4 diodes used-that is a full wave bridge rectifier- and you get smoother DC and don't need a center tapped transformer- when only two diodes are used that is a Full wave rectifier but you need a center tapped transformer-
    Here's a link that will explain it fully

    https://www.electronics-tutorials.ws/diode/diode_6.html
    Wow, went to the link, and am reading. I'm trying to wrap my head around this, I'm a newbie to electrical so this is new. I'll get back once I digest all of this. Thanks..............
    Steve

  5. #5
    Join Date
    May 2018
    Posts
    10

    Re: Snap-On 110V YA219 Mig Welder Diode Question

    In an attempt to understand how this welder works I've been researching/reading a lot of different web sites and think I have realized the deal about center tap transformers and how it applies to my case. Now, could someone please look at the attached picture and verify the components of this welder I have questions on?

    1) The heat sink is also acting as a conductor and along with it's other duties?

    2) What is the unit under the transformer? I believe it's a reactor and I'm thinking it's to help smooth the current?

    3) Capacitor is the blue cylinder, right?

    4) The transformer has a lot of wires going into it so I'm guessing their multiple tap's for the different power levels?

    Thanks in advance. I used to do okay with early automotive electrical stuff but this AC power supply stuff is all new.

    Steve
    Attached Images Attached Images  

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
RSS | Home | Penton Media | Contact Us | Subscribe | For Advertisers | Terms of Use | Privacy Statement