Board burning

[drhex]

Hi,
Experienced something new to me on the weekend when I put a PDB with repaired acid damage into a pin. It started arcing and burning underneath the high power solenoid connectors (this is a Sega). Putting 50V into the pins on the bench replicated this behavior, the board burns to a crisp around the header pins. Only thing I can think of is that the electrolyte soaked into the board turning it sufficently conductive to burn it up. Did anybody ever have something similar/a better explanation?
Florian

 

[Ruaraidh]

Once a board is burned slightly, it becomes conductive and electrolyte is obviously conductive as well. You will need to get into the board with solvents to remove the electrolyte then a dremel or similar to remove all traces of carbon and then any damaged tracks will need to be replaced with wire traces. Can be done though. Have repaired a few high powered amplifiers (200W+ like this where a Darlington had failed and scorched the board).