The main board is the plant’s electrical hinge. Heat, repeat trips, or no spare ways usually mean more than a single breaker swap.
Log these symptoms
Abnormal temperature, loose terminations, smell of overheating, phase imbalance, and “temporary” cables that never left.
Before solar or new machines
Study capacity and tie-in points first. Energy projects that ignore the MDB tend to redraw during install.
Engineering response
Measure load, scan thermally on a cycle, and decide between point repair, phased upgrade, or a redesign when the old layout no longer matches reality.