Years ago I had to add some pneumatic solenoids to for a guard and hold downs with time delays of a large panel saw with a 20" blade in a cabinet shop.
After trying unsuccessfully to interface all of the new components into the existing control circuit I found that the control wiring had been changed form the original schematic. It was simpler to rip all of the wiring and rewire the panel by wiring in each limit switch, each relay, contactor, etc, and then adding the modifications.
Sometimes trying to figure out the mess takes more time than it would take to start from scratch and rewire the whole thing.
