The entire charging current (30-50 amps?) goes through the bulkhead connector, in and out. Any oxide in those connectors and the whole thing melts. Standard fault on the earlier models. They fixed this sometime around 1970, I believe, maybe earlier.
If you bypass it, you only measure a voltage and hardly any current passes thru, keeping the bulkhead connector from destroying itself.
If you want pictures of a molten connector, I think I have some in my thread. They're attachments now, though. I need to fix that ...
