Mast wiring

[Craig Illman]

I'm pulling the mast to do the standing rigging in a couple weeks on my fifteen year old C34. I'm replacing the masthead sheaves, and generally going over everything else. I purchased new cable for the wind transducer, should I be doing the same for the lighting as well? How is the steaming light/deck light/anchor light wired? Is it multi-conductor up to the steaming/deck light, then duplex up to the anchor light? Given what I found with the factory battery cables, I don't expect this wiring to be premium either.

Appreciate anyone's feedback.

Craig Illman

[tstrand]

We just rewired the mast lights on our 1988. There was 18-3 to the steaming / deck light and a separate 16-2 to the anchor light. I don't know whether they were original or not but both were non-tinned, and creeping corrosion was giving us continuity problems. We replaced it all with Ancor marine tinned 16-3 to both locations. The extra wire to the masthead is a spare for an eventual tricolor or windex light.

Note that 16 gauge doesn't meet the 3% voltage drop spec for our anchor light (0.7 Amps, ~140 feet round trip) but I figure that's less critical than the steaming light, for which we're okay (0.7 Amps, ~90 feet). This was necessary because our conduit is too tight to fit a larger gauge (we have heavy VHF cable).

I also installed a terminal strip at the mast base just under the cabin sole. The old "installation" was butt-joint connectors with a mile or so of electrical tape wrapping them.

Good luck,
Tim

[r_bond]

Tim,

Great info.  My mast is down right now so I probably need to check/replace the same.  I have 3 questions:

1.  For the help of those of us who are "electrically-challenged"...what do you mean by "16-3"?  I'm guessing 16 gauge, 3 strand wire?  (What I DON'T know about electrical circuits would fill volumes!!). 
2.  Is there a way to test for the continuity problems you mentioned?
3.  Is there a way to test the VHF cable to see if it should be replaced.

I also really like your idea of the terminal strip at the mast base.  By any chance do you have a pic of this?  If not, what product did you use?

Thanks,
Rusty

[BillG]

I had my mast down 2 winters ago and took the opportunity to do a rewiring job on my 1987.  As mentioned, the wire up to the steaming/deck light was an 18/3.  Today's concensus, including the opinions of Nigel Caldor, is that each circuit should have its own ground, so I replaced this wire with a 16/4, meaning that both the steaming light and deck light would have a separate ground. The anchor light was replaced with a 14/2. I also took the opportunity to replace the anchor light with something with a little bit more  heigth and light.  At the same time, I also  replaced the VHF cable with new coax, an RG-8x and ran a separate cable for my newly attached TV antenna. I had no problem running these new lines down the conduit.  One caveat however, at the bottom of the mast , there is an oblong cutout where the wire comes out of the mast at the very bottom.  It is important that you take a metal file and extend this cutout for your new and oversized wires that you have run.  Failure to do this might result in crimping and or cutting the wires when the mast is restepped.  As you may noticed, I upgraded the sizes of all my wires and cables to prevent voltage or signal loss.
As a final suggestion, I ran all my new lines directly to the panel without any connectors or terminals.  My thought was that any cut in the wire, no matter how you make the connection, is a problem waiting to happen. It could be that I never take the mast down again, so why do you need the connector.  Just in case however, I left about a foot of extra wire/cable rolled up  after it comes out of the mast so if I  ever need to  take the mast out again  I will have enough  to add some connectors.

[tstrand]

Rusty,

1) Sorry, yes, "16-3" means 16 gauge, 3-conductor.

2) In our case the continuity problems were obvious: the mast lights would work intermittently, even though all of the bulbs were good. If your lights work and don't flicker, you can measure resistance of each circuit using an ohmmeter. But to know whether you have a problem you'll need to know what the resistance should be, and that depends on what wire gauge, circuit length and bulb size you're using. The bottom line is if you don't have problems with your lights the upgrade is optional. But if your wiring is 15 years old it's probably untinned and corroded, and your problems are not far off.

3) There's the traditional way (try to call someone on VHF, preferably someone far away) and the accurate way (buy or borrow a $50 standing wave ratio meter (West Marine 253478, but cheaper elsewhere)). The latter measures the VHF signal reflected back down the coax by imperfections in the cable, connectors, and antenna. If you do replace the coax, I'd recommend the RG-8x as Bill mentioned (and we have). It's thick (0.4" or so) and expensive but you'll lose only 1 dB (20%) of your power to cable losses versus about 3 dB (50%) for the cheaper, thinner stuff.

I don't have a picture of the terminal strip I installed but it's a standard strip from McMaster; go to www.mcmaster.com and search for "terminal strip." I think I used 7527K86. I screwed it into the mast step just in front of the mast. I used non-insulated ring terminals because I used shrink-wrap tubing with the hot-melt glue inside (great stuff, and also from McMaster).

I like Bill's idea of hard-wiring all the way to the panel, especially because those connections live in the bilge space. But I'd still prefer the terminal strip as I like to have test points, plus the terminal strip is easy to inspect. Individual choice, as usual.

Good luck,
Tim

[Paul Blumenfeld]

Tim,

You just adde one MORE thing to work on with my mast down!

It started off as a simple replace standing rigging with the mast up.  Now I'm pulling the mast down Dec 27th.  With rigging, lights, sanding, painting, wiring , masthead sheaves, roller furling, etc... I may get it back up in time to sail in May!

(But it is better to do everything at once and get it all done.  )

Thanks for the suggestion.

Paul

[Ron Hill]

Tim : Rule of thumb on 12V wiring:  Use 14 gage size wire, unless you have a short run in which you can get by with 16 gage.  Heavier is always best. 
As heretic, I always crimp AND solder(then cover with heat shrink).   

[Tom Soko]

Rusty,
Picture #34 at the following address is from my C36, so the configuration is not exactly the same, but you should get the idea.  At the base of the mast I've used terminal strips and nylon cable clamps, all mounted to a piece of plywood, to keep the wiring out of the bilge and dry.  Once a year they get a spray of Boeshield T9.  Hope this helps.

http://www.imagestation.com/album/pictures.html?id=4288188659&code=13911531&mode=invite&DCMP=isc-email-AlbumInvite