Mast Wiring Complete

It's finally starting to warm up a bit, although not as much as I'd like but sufficient to get back to work on projects.  One of the final projects to tackle before the launch this summer is the mast and although the bones of it are sound, a lot of work needs to be done before it's ready to stand up.  All told there are 5 mast projects that need to be completed (or are completed).

1. Masthead removal and rebuild - completed: here
2. Wiring - this post
3. Mast track - Tides marine sail track
4. Rigging tang installation
5. A good scrubbing

When I bought the boat, the wiring was in sad shape and need 100% replacement. I left a lot of it in place after I dismantled the masthead so I could use it as a guide when it came time to replace it all.  Also, the original fixtures were incandescent which drew significantly more power and consequently, heavy gauge wire.  The good news is that the new fixtures I'm installing are all LED and can use 16 gauge wire instead of 12 gauge in the original, giving me more room in the mast tunnel for robust wiring (it's tight, see schematic with tunnel circled in green).  In total there are 4 fixtures that need wiring in the mast: the VHF antenna, the anemometer for wind speed, a combination tricolor/anchor light at the top of the mast and a combination steaming/foredeck light located mid mast. 

Since the VHF and anemometer cable have already been determined (Raymarine for the anemometer and radio antena physics for the VHF), I needed to find some robust 16-18 gauge wiring to send power to the tricolor/anchor and steaming/foredeck lights.  I could have gone with 18 gauge to keep things smaller, but I only want to do this once and I want it to last so I purchased a spool of 16 gauge triplex bilge wiring that should satisfy my needs. The reason for triplex wiring is that each of the fixtures has 2 positive leads and 1 common ground so that each function on the fixtures can be controlled independently.  The final reason for choosing the triplex bilge wiring is that is it beefy and should stand up to many years of abuse hidden in the mast.

Installing the steaming/foredeck light was pretty straightforward and the mounting holes were a perfect fit with the original fixture (including the genoa guard).  The tricolor/anchor was slightly more complicated and I'm glad I pulled and rebuilt the masthead unit last year and hadn't reinstalled it, because I needed to find a slightly different mounting location for the tricolor/anchor (the mast never had a tricolor on top before, just an anchor light).

I found a good location on the masthead where it was out of the way of other equipment on top and allowed me to use the same hole to pass the wires through so that they didn't interfere with the halyard sheaves.  after I tapped new screw holes and mounted the light, I decided to test it before reinstalling the whole assembly and while I had tested it when I pulled it from the box and everything worked fine, once it was mounted, only the tricolor worked unless I tilted the whole masthead at an angle. I decided I must have caused a short or loose connection when I mounted it, so I took it off and pulled the whole unit apart and re-torqued all the connections, but it was still intermittently turning on and off.  Next I put the tricolor light in the anchor socket and the anchor light in the tricolor socket and the anchor light was still acting funny.  I thought, "Ah, it must be a bad LED bulb" and found the serial number online and was just about to order another one when I noticed in the specs that this bulb had a light sensing diode on it, so it only turns on "Dusk to Dawn".  Duh... 

Sure enough, when I located the diode and put my finger on it, the light turned on and back off again when I took my finger off.  As it turns out, when I initially tested the fixture out of the box it was nighttime. When I tested it after I mounted the whole fixture and thought it was related to the angle it was tilted, it was actually because I was tilting it away from a window causing it to darken enough to turn the light on...  Moral of the story: "I am an idiot", but it was nice to find a new feature on the light that I hadn't expected.  The fixture as sold does not come with the "Dusk to Dawn" diode, so the previous owner must have replaced it and put it back in the box.  

With that revelation finally understood, I remounted the fixture on the masthead and took both fixtures over to the boat to get them installed.  I ran 2 lengths of triplex bilge wire from the base of the mast to each fixture and crimped the connections with shrink connectors.  Then I heated up all the connections with my heat gun to shrink the connectors over the wire until I could see the little squirt of glue coming out around the wire.  

The final part of the installation for the tricolor/anchor light was to run the halyard chase lines through the sheaves in the masthead (2 jib, 1 main) and tap the masthead back into place and bolt it on.  To test it all, I brought over a smallish 12v lithium battery and stripped the tricolor bilge wire at the base of the mast and powered up each function. I'm happy to report that after the silliness with the "Dusk to Dawn" diode, everything worked as expected (as long as I cupped my hands around the anchor light because it was still bright out).