I'm fixing the mast lights on my new to me boat. The only lights on the mast are the steaming light and anchor light. The cables, 18/2 for steaming and 16/2 for anchor, exit the mast through two small holes on the side of the mast about 6" from the deck. There's about of foot of wire left after they exit. There are two holes drilled through the deck right at the edge of the mast step and the wire are lead through there. Some pictures:
And the inside:
The mast light has a new 16/2 cable running loose above the settee from the fuse panel, out through the hole in the deck at the base of the mast (filled with silicon sealant, which has failed), and then to a pair of "bullet connectors" to the wire coming out of the mast. The connectors were wrapped in some electrical tape. The connectors were all corroded and there is corrosion running up the conductors in the mast wires. Nothing was sealed with heat shrink.
The steaming light uses some of the original 31 year old wiring to get from the panel to the mast and looks to be 18 or 20 gauge. The conductors are stiff and black. It was joined with crimp connectors inside the boat to the mast cable, which exited through a hole in the deck and goes up the mast.
Both lights were connected to the same switch on the panel, which doesn't make any sense, since you'd never want steaming and anchor to be on at the same time. Rather than get a new panel (all switches in use), I was going to add a double throw switch after the panel's "Mast Lights" switch. One position would turn on anchor and the other steaming. I'd run a single 16/3 cable from the panel to near the mast. Common ground and two hots coming from the double throw switch. Any flaws in that plan?
But now the question is how do I join this 16/3 cable to the two 2-conductor cables exiting the mast? Join them inside the boat or outside the boat?
Inside would be more weather proof, but then how do I disconnect them to drop the mast? It's not a trailered boat so that won't be happening often, but I'd like to be possible without having to do extensive exectrical work. Especially anything that would involve cutting wires and making them shorter each time I need to disconnect. The deck holes the wires go though are pretty small. I can't put much of a connector at all on the end of the wires and still fit them through. Maybe a spade terminal on each conductor would fit.
If I join the two cables the one 16/3 outside with just a straight splice the butt connectors and heat shrink it should seal well. I'll only have one cable going through the deck. But if I ever need to run the wires through the mast I need to break my splice.
I'm aware of cable clams. But I'd have to make a new hole in the deck near the mast and that worries me a little. Is it possible to run two cables though the same clam? The cables aren't round either, would that be a problem? The 16/3 cable is pretty flat in fact.