Can i ask a question? On your wiring diagram many pages back, are your negative wires all bundled/soldered together as one and then connected to the power plug? Are they all separate but on another board somewhere? Just wondering where all the negative wires end up going. Awesome job btw.
As I wired the sets of LED’s in series I connected the negative ground wire from one set to the ground wire of the next set of LED’s to reduce the amount of wires, so they were spliced together, then due to the amount of LED’s I used, I had to connect the ground wires to a grounding rail on an extra board I made.
The picture shows the layout of the board I made with a long ground rail for the negative ground wires to connect onto and so reduce the number of soldered joins I had to make, believe me if I tried to solder all the negative wires together I would have had more solder that wire, I would have ran out of shrink tubing in no time!.
Or you can use a (Electric Cable Wire Connector 10 Positions Screw Barrier Terminal Strip Block) to connect your ground wires to, here is a link:-