PCBs have been demonstrated to cause a variety of adverse health effects. They have been shown to cause cancer in animals as well as a number of serious non-cancer health effects in animals, including: effects on the immune system, reproductive system, nervous system, endocrine system and other health effects. Studies in humans support evidence for potential carcinogenic and non-carcinogenic effects of PCBs. The different health effects of PCBs may be interrelated. Alterations in one system may have significant implications for the other systems of the body. The potential health effects of PCB exposure are discussed in greater detail below.

I want to learn more about troubleshooting electronics. If I just went and bought another board for my house gen when it went out, I wouldn't of learned as much as I did when I fiugred out what went out and how to fix it. Ive fixed a family memebers handheld sonogram machine, and other various electronics and I always learn when I do this kind of stuff. If all else fails I guess Ill just buy the replacement board, but id rather spend twice as much time and money and fix this one. lol Im hoping someone sees something or has an idea.

If anyone has a suggestion of something I should test, or to look at, please share. Is there another component on the board that would cause this issue? This issue literately happened while welding, no power outages or lightning strikes, wasn't dropped or got whet. Im out of ideas ...... This machine was farily new when this happened. I had welded maybe 1 or 2 other projects with it. It was a clean hardley used machine, I just don't get what went out. I can buy a replacement PCB at about $ 300 but this isnt about saving money or trying to be "cheap",

Also on the schematic it shows 2 large 55a triacs SCR1 and SCR2 the info on the schematic drawing says the info doesn't apply to all models so I guess that second traic is on another model? Because mine only has the SCR1. The left side of the board is for wire feed and gas valve as well as a spoolgun / spot timer addon kit (which I don't have but want if I ever get this fixed). So the right side is all the current controls. Ive checked all the diodes and resistors (tested with them on the board) and nothing jumps out.

So I take a closer look at the board and schematic on page 110 of the manual above and I see a voltage control amp x7 LM224N which feeds an optocoupler IL4208 that controls the main triac src1. I had an LM3224N from another project and replaced it then removed the optocoupler from PCB and it tested fine. When I apply 5vdc to pins 1 & 2 I get different Ω readings so I figured its working. Try board again and it still does the same exact thing. Anyone got any idea where next to look? Am I missing something?

A printed circuit board (PCB) mechanically supports and electrically connects electronic components using conductive tracks, pads, and other features etched from copper sheets laminated onto a non-conductive substrate. A printed circuit board has pre-designed copper tracks on a conducting sheet. The pre-defined tracks reduce the wiring, thereby reducing the faults arising due to loose connections. One simply needs to place the components on the PCB and solder them.

The properties that make aluminum such a profitable metal are: its lightness (about a third of the weight of copper and steel), corrosion resistance (very useful characteristic for those products that require protection and conservation), resistance, is a Good conductor of electricity and heat, it is not magnetic, it is not toxic and it is very ductile.