[CA] [CA11] ST60 depth transducer connection to iTC5

[ddoles]

I installed an iTC5 converter to use my existing ST60 depth, wind, speed transducers in a new Seatalkng network. Initially the depth was working only intermittently, then not all. It just showed dashes on the new i70s instrument. I replaced the old spade connectors on the depth transducer wires and reconnected them to the iTC5. After a bit of plugging and unplugging, I realized the depth works fine if I plug in only the blue and black wires. Once I plug in the "screen" wire, the LED in the iTC5 depth panel flashes and the instrument reads only dashes. Unplugging the "screen" wire and everything is fine again. It seems I can just use it with only the blue and black wires, but am I missing something? What does the "screen" wire do? It seems to only cause problems, but it must have a useful purpose. Am I OK to just use blue and black wires only?