Kind of looks like a 100 Amp Lighting Contactor drawing >100 Amps across the Contacts.
Looks more like an alignment problem is to blame here, which is keeping the Contacts from seating properly when closed.
This would be from installing the Lighting Contactor assembly over a non-flat surface, then tightening everything down - causing the Contactor's back mount plate to be bent; resulting in the Contacts being misaligned (not a solid and full connection) when they are closed and latched in.
Scott35
