I believe I understand the requirement is to join (with a jumper wire of sorts) the V- (negative output) of multiple power supplies. If this is true, and I have a power supply and pixel controller on one side of the yard that power the start of a string of nodes, then another power supply 15 feet away that inject power into the pixel string, do I still need to run a 15 foot cable between the two power supplies just to connect the V- outputs? I believe I also have to splice the pixel string negatives together so they are both basically connected to both power supplies? Thank you in advance! I never claimed to be an electrician, I just like lights!