single wire or duplex

Wiring your boat, How to Wire Lights/Accessories, All things electrical other than actually powering your boat by electric motors.

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chugalug
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single wire or duplex

Post by chugalug »

:roll: is it better to wire boat with a single wire as opposed to using duplex?also does the negative wire have to be of the same length as the hot wire?If using #10 wires for horns ,spotlight can one use #10 for other things requiring 12 or 14?reason I'm asking is that the smallest roll I can purchase is 100ft.would like to use up as much of it as possible instead of buying 100 ft of each size(#10 to#14)#16 will be longer roll for lights and nav lights and bilge blower. :roll:
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DrBryanJ
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Re: single wire or duplex

Post by DrBryanJ »

Chug, I'm just starting to figure wiring so hopefully someone with experience can chime in. I believe you can use a larger size wire without any problem. For example use a 10g instead of 12g or 14g. You can't go the other way . Pos and neg do not have to be same length.

Bryan
Bryan

Building a malahini "Mona Lisa"

My wife said "If I build a boat, she's getting a divorce."
We're still happily married, but now she just wants "the dam boat out of the garage."

rleete
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Re: single wire or duplex

Post by rleete »

Larger wire is always okay. Smaller is never okay (risk of overheating & fire). Follow recommended AWG for whatever you are installing. Most electrical items (bilge pumps, instruments, etc.) will have a recommended wire gauge. Go bigger if the wires extend a long way. Or, you can install terminal blocks, and then use a single, larger wire to travel the length of the boat, eliminating the need for multiple runs of power and ground. Make sure the single wire has large enough capacity to handle all that is attached to it.

Wires do not have to be the same length, within reason. Over the course of say, 10 feet, one wire being 8-10 inches longer will make no difference.

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chugalug
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Re: single wire or duplex

Post by chugalug »

:D Thanks.Duplex route is a little cheaper vs.2 wires .How close to the batteries do I have to locate fuse box.was thinking also of locating house battery forward and starting battery back under motorwell.or should they be together?Have few parts ordered but will have get wire later.
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Jimbob
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Re: single wire or duplex

Post by Jimbob »

West marine has a pretty good article on wiring. Here's the link.

https://www.westmarine.com/WestAdvisor/ ... Tech-Specs

I believe somewhere, glen-l has an article on basic boat wiring.
I think there is also something in the coast guard boat manual. (not sure what it is called but it discloses all the coast guard regulations)
All of my stuff is at home so I am doing this from memory (what's left) :roll:
I read somewhere that there is special wiring for marine applications. I would purchase from a marine supplier rather than from HFT or Home Depot, etc.

There are standard wire colors for different things. The publications describe what color for what. Ex bilge pump, blower, etc. I would suggest following the "standard". It also makes sense to have distribution blocks.
Hope this helps.

Jim
Jim Neeley
Building a Barrelback in Sacramento, CA
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DrBryanJ
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Re: single wire or duplex

Post by DrBryanJ »

This web page does a good job of explaining things electrical http://newboatbuilders.com/pages/electricity1.html Page 13 http://newboatbuilders.com/pages/electricity13.htmltells you how to design a basic system.

Bryan
Bryan

Building a malahini "Mona Lisa"

My wife said "If I build a boat, she's getting a divorce."
We're still happily married, but now she just wants "the dam boat out of the garage."

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mrintense
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Re: single wire or duplex

Post by mrintense »

I also want to reiterate that the wiring diagrams that Glen L sells are also quite nice.

This is one of those areas where I believe it pays to spend the extra time and effort to understand what you need. It's an area of my own build that I am just starting to have to worry about (from an actual wiring the boat perspective) but I've been reading on this for years trying to get it clear in my mind. Still not even close to 100% confident but like everything I've done so far, going to learn as I go.
Carl

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chugalug
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Re: single wire or duplex

Post by chugalug »

:D I already have the Glen-L stuff and got book from Bue Seas.Just trying to figure out what I need.and to get all you folk's input too.Kinda in a rut.thanks
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Hercdrvr
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Re: single wire or duplex

Post by Hercdrvr »

Just finished wiring my Malahini ,

Battery is forward under the bow

-Ran 10G from Bat to junction box mounted on backside of dash

-Ran 14G from junction box to individual components

-1G from Bat to Engine, 15 ft

- 10 amp fuses in every slot

It's all low amp draw stuff. Two bilge pumps on a circuit is biggest draw, maybe 6 amps. Everything working fine so far,
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IMG_2485.JPG
IMG_2406.JPG

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chugalug
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Re: single wire or duplex

Post by chugalug »

:D Thanks!!Why didn't I think of individual switches.I've been pricing other ones.over 100 bucks per panel.Yikes .Individual ones will fit in "Chug" better than a plastic one.got fuse panel coming like yours. :D
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Hercdrvr
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Re: single wire or duplex

Post by Hercdrvr »

Chugalug,
I don't know how extensive your electrical system is going to be but mine is pretty simple.
-Interior/exterior lights
- blower
- bilge pumps
- horn
- small inverter for charging phones and Bluetooth speaker
- Dome work light behind the dash,
I used the better part of two 100' spools.

Matt B
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Work light under bow
Work light under bow

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chugalug
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Re: single wire or duplex

Post by chugalug »

:D Thanks again.I'm thinking on single battery to start with.my motor has rope as well as electric start.will be using led nav lights,bilge blower(not neccesary for outboard but have mounted fuel tank) and bilge pumps.also depthfinder and guages.small led flashlights work good for maintenance work.these little guys are a lifesaver for working in dark places
IMG_0918[1].JPG
fold-up hanger hook on back as well a magnet to stick anywhere
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mrintense
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Re: single wire or duplex

Post by mrintense »

I'll be building LED light strips into all my storage spaces. Fans in the cabin, bilge pumps, electronics (some), nav lights, instruments, horn, and a robot to run steering when I get lazy.

Just kidding about the last item!
Carl

Crafting a classically styled Vera Cruise

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chugalug
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Re: single wire or duplex

Post by chugalug »

:D Carl; is that robot like the autopilot on the "Airplane" movie? :lol:All kidding aside ,I just found a place where I can get larger wire by the foot so will be pulling tape out and measuring for bilge pump and smaller wire for other apps.
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BayouBengal
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Re: single wire or duplex

Post by BayouBengal »

I was able to order a 10 circuit wire bundle from this site http://www.ezacdc.com/boat-wiring-produ ... g-harness/. I just ordered the non-snap together harness. I didn't actually use the harness as they put it together, but what was convenient about it was that you got all the different wiring colors that you need for wiring a small boat without having to order multiple rolls of wiring. I'd spoken with the owner of the site and got the impression that he's running fairly small operation and just makes up the wiring harness as they are ordered. If that's true, in retrospect, I could have just had him send me 15 foot lengths of each of the colors since I took the harness apart anyway. I cut the wires specifically to the lengths I needed and used connectors similar to this http://www.ebay.com/itm/Molex-MLX-Conne ... Sw4A5YzBdR to custom make up my own snap-together connections for easily connecting and disconnecting.

In regards to the original question, definitely two wire. And 16 guage wire will be fine for most of your circuits.

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