Wire Guage

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TritonSailor
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Wire Guage

Post by TritonSailor »

When rerunning wire for normal use, ie..inside lights, running lights, nav gear. What guage of wire do we use? Do you run single strand or jacketed? Thanks in advance.

Jeff
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Tim
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Post by Tim »

For normal lighting and electronics circuits, usually 14AWG is more than sufficient on the sort of boats we're talking about here. Sometimes longer runs, because of potential voltage drop, are better off with 12AWG. Of course this generality excludes extremely high-draw electrical items like windlasses, etc., which require something larger.

Single conductor or sheathed is a personal decision one must make. For everyone that likes single wires, there's someone who prefers sheathed. That's fine. They both work.

I find that sheathed 2-conductor cable always costs a lot more than a pair of single wires, and since I also find single wires more versatile that's what I use in most cases. Sometimes the sheathed stuff is nice if you know a certain run is going to be visible in the completed interior, but as a general rule I find it's less convenient and more costly.

Your choice.
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Post by Hirilondë »

I think you will find most professionals agree with Tim, on both size and individual conductors. Many lighting runs can be done in 16 AWG. But the reasons for going 14 AWG is physical strength of the wire itself. It isn't safety as you fuse to wire size anyway.

Check the specs on the nav equipment and electronics of any kind. Some stuff has an incredible voltage range, others may be sensitive to getting near the full 12 volts. My GPS runs on less than 10 volts, my stereo cuts out at 11.5 volts, go figure. I discovered this the first year when I had only one battery and no on board means of charging.
Dave Finnegan
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TritonSailor
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Post by TritonSailor »

Thank You Tim. Not to beat a dead horse, but would 12 AWG be sufficient for runs up the mast for navigation lights for instance? Especially if you were going to have multiple lights on one run, like a tricolor with a mast lamp. I don't know if I could do that or if it would be prudent, I'm just trying to get an idea of how things work.

Thanks.

Jeff
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Tim
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Post by Tim »

12 is typically fine for the length of conductor you are talking about in a Triton spar; it's what I have running up my mast. To be sure, check the specs for your individual products versus the commonly-available tables for 2% and 10% voltage drop, to be sure it works for your individual case. Unless you're mounting high-bay sodium security lights on your mast, you ought to be fine with 12 AWG.

However, I avoid common grounds when wiring, so that means individual wires for each mast light. You need individual supply (positive) wires for each individual light anyway.
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Post by Capn_Tom »

If you don't like using the tables that are in the electrical books, Blue Sea has a handy wire gauge calculator on their website that addresses the various de-rating factors www.bluesea.com
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TritonSailor
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Post by TritonSailor »

Thanks guys, this is really helping me out!

Jeff
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Re: Wire Guage

Post by Skipper599 »

I'm at a point where I need to start thinking about replacing external wiring ... eg: nav lights etc. ... is there special "marine" wire available or does one use automotive?

In particular, I notice on my Selden mast, the cable (probably European) to the nav lights has two wires 'embedded' in a grey, round, solid, rubber-like material (approx .125" dia)... which I've been unable to find in any marine or automotive supply store.

This type of wire appears to me that it might be totally impervious to salt water penetration, unlike other wires that are 'loose' inside a tubular like sheath. I would certainly like to use this type of wire again if at all possible. ... Does anyone know where such wire can be obtained?
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Re: Wire Guage

Post by Hirilondë »

Skipper599 wrote:. ... is there special "marine" wire available or does one use automotive?
Yes there is. The primary differences are much smaller strands, and hence more of them. This makes the wire more fleixible and less prone to breaking from vibration. The other big difference is that the strands are individually tin coated. This reduces the tendency for corrosion. Find a reputable marine supplier and ask for marine wire/cable.
Dave Finnegan
builder of Spindrift 9N #521 'Wingë'
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Ceasar Choppy
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Re: Wire Guage

Post by Ceasar Choppy »

What Dave said.

Re your round wire, try this:
http://shop.genuinedealz.com/Marine%20G ... t%20Cable/
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