mig welder rectifier

[robert931]

Hi there i have bought a mig welder for parts or repair with the intention of fixing it.

it starts and feeds wire ok but it wont strike an arc. so i took a closer look at the rectifier and it seems the botom 8 diodes are burnt out / wires burnt off them.

so my questions are.......
1 what caused these diodes to fry will it do it again if i replace them
2 the code on the diodes is t25 4 E9 and some are F9. can any one reccomend some replacements. I think they are the same as car alternator ones but not sure.

thanks in advance robert

 

[(*steve*)]

A photo will tell us a lot more...

 

[robert931]

 

[robert931]

how do you upload pics

 

[robert931]

http://www.ebay.com/itm/Clarke-180EN-Mig-Welder-Rectifier-Weld-Parts-WE-6916-/200589877163

its something similar to that same idea just diodes pushed into the aluminum heatsink i take it

 

[davenn]

how do you upload pics

1) ... click on Go Advanced button below your text box
it opens up another section below the text box with a button called Manage Attachments

2) ... click on Manage Attachments button and a small window will open up so you can upload a file from your computer ...
4) ... click on Browse button and go to the location on your puter where the file is
5) ... select that file
6) ... once its selected it will appear in the box to the left of the Browse button
7) ... click the Upload button and the file name will appear under a heading of current attachments ( in that small window)

Dave