Thread: PING: Iggy
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Bill[_42_] Bill[_42_] is offline
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Default Lincoln TIG welder problems

On 12/27/2011 12:28 PM, Jon Elson wrote:
Michael A. Terrell wrote:



That sounds like you may have some bad electrolytics on the
conrtroller board. The ESR drops some as they heat up, and start
working.


The main board has dozens of large Tantalum capacitors, and older
tantalum caps tend to fail with various symptoms when not kept
polarized fairly frequently. I already fixed one bad one that was
pretty easy to locate, the postflow timer. This fault, if it is
a capacitor, is going to take more detective work.

The board is conformally coated, so any rework is a very painful
process involving carving the coating off with an X-acto knife.
So, shotgunning all the dozens of caps on the board is not practical.

Jon


you may want to spend $80 and buy an ESR meter - that will help you find
bad caps easily - there is one called "blue" that is a kit, easy to
assemble, you can get it from ebay or from the factory