Re-Wiring During Refit

[Stumble]

Phil,

The term "marine grade" is a trademark held by Ancor to describe their tinned stranded wire which does meet ABYC specs. The fact that the USCG guidebook uses the term incorrectly isn't really at issue, any more than the fact that my wife called all carbonated beverages "coke". Other companies may call their wire "marine quality" "marine primary wire" "duplex marine wire" ect, but if it's called "Marine Grade" it is Ancor.

That being said it is important to use ABYC (prefered) CFR (required) compliant wire, of which Ancro is a high quality manufacturer.

[CarinaPDX]

My recommendation to the OP is to either commit the (substantial) time and energy into learning what is required to design a proper system or turn it over to an ABYC certified boat electrician. The original post would seem to indicate that there is a long ways to go for the OP to do it himself. That sounds a bit harsh, but needs saying. There is nothing simple about a safe and reliable electrical system. Discussing wire standards and color codes is about as basic as it comes. How about grounding (AC, DC, radio, lightning)? Isolation transformer or galvanic isolator? ELCIs and GFCIs? Does the OP have a copy of the relevant ABYC standards and does he have the background to understand them? Or better, know when to deviate from them? I have seen too many unsafe boats to want to encourage more DIYers unless there is a willingness to grapple with the entire problem.

I do not wish to offend or discourage the OP - just trying to communicate the size and importance of the task.

Greg

[GordMay]

As DeepFrz noted:

Electrical Cables for Boats - UL 1426 (BC5-W2)

1 Scope

1.1 These requirements cover electrical cables for boats. The cables are intended for use in marine pleasure craft and consist of a single insulated conductor without a jacket (primary wire) or of two or more insulated conductors with or without an overall nonmetallic jacket (duplex, triplex, etc cable). Each boat cable is rated as follows: 600 V; 60°C (140°F), 75°C (167°F), or 90°C (194°F) wet; and 60°C (140°F), 75°C (167°F), 90°C (194°F), or 105°C (221°F) dry. Boat cable dry-rated 125°C (257°F) or 200°C (392°F) may be investigated. A boat cable so marked has insulation (and jacket if a jacket is used) that is for use where exposed to oil at 60°C (140°F) and lower temperatures. Boat cables employ stranded copper conductors that are 18 - 4/0 AWG for multiple conductors and 16 - 4/0 AWG for single conductors.

1.2 The ampacity of a boat cable shall be as stated in the US Coast Guard regulations Title 33, Chapter I, Parts 183.430 and 183.435 of the CFR.

➥ https://law.resource.org/pub/us/cfr/....1426.1986.pdf

Marine wire, boat cable, and marine primary wire that meet UL 1426 approval will be marked accordingly. The markings you should search for on a UL 1426 approved wire will be "UL 1426," "Boat Cable," or "BC5-W2". The UL requires the marking to be printed on the electrical cable.

BC-5W2 is another marine specification. It is a heat rating designation on UL 1426 (105 ºC in a dry environment, 75 ºC in a wet environment). The term "boat cable" may sometimes be a specific term used in certain cases to indicate the BC-5W2 approved wire. BC-5W2 is suitable for use on boats and non-commercial marine vessels.

[Horror Hotel]

Doing it safely, with quality wire (tinned or not) in a professional manner has little to do with the ABYC. That book is like the bible to some people, don't believe the hype.

[goboatingnow]

I notice UL 1426 does not mention tinned conductors

Dave

[goboatingnow]

Originally Posted by Horror Hotel

Doing it safely, with quality wire (tinned or not) in a professional manner has little to do with the ABYC. That book is like the bible to some people, don't believe the hype.

Absolutely and there are several areas where other worldwide standards take a different view. Furthermore ABYC is good for conventional systems installed in GRP boats. Once you stray away from that into metal boats , isolation transformers , DC boats ( invertor driven AC ) you have to apply first principles and not ABYC.

its not difficult to install a simple AC system on a boat , it doesn't need to be tinned wire for example but obviously if you can afford it , use the best.

My suggestions would be

1. always use stranded flexible cable specified appropriately

2. Secure the cable well and protect against chafe

3. Use a RCD or GFCI to provide whole boat protection. Install the usual AC panel system , insulate the rear of it by the way

4. Be tiny and neat in your connections

5. For a US boat , ground as per ABYC. ( even though I personally would never interconnect DC and AC earths. )

If you don't understand basic AC wiring and systems , don't install it yourself

Dave

[Cuttyhunk]

Originally Posted by Noreastern

Part of our refit is to install all new wiring. Originally wiring was single conductor single insulated 14 gauge wire with a rainbow of colors. All is now removed except for where we will use the old wire as a "fish string" for the new.

Our plan is to use 16 gauge wire for the majority of DC wiring and all of it red/yellow for positive and black for negative. AC will be very basic 30 amp shore power to two outlets which are wired black for hot, white for neutral and green for ground (basically an extension core hard wired into boat). My question is should we use single conductor, single insulated wire like the original or would it be preferred to use two and three conductor double insulated wire?

I started to reply last night because your plan to use yellow for a positive conductor freaked me out, but I knew others would jump in soon enough. To ignore ABYC standards, and/or ignore the good books out there, requires enough knowledge to know that what you are doing is safe. The whole point is to keep the risk of a fire or of zapping someone or totally corroding out a thruhull and sinking the boat to a minimum. Those three disasters are not hard to achieve if you get cocky.

No, ABYC is not perfect, and I don't agree with all their stuff (and yes, I am a member, and a master tech, blah, blah, blah), but their goal is to keep risks to a minimum. You have a 38 foot boat. You need to learn enough about wiring to understand that you will not be able to use 16 gauge wire for the majority of your wire runs on a 38 foot boat. And that the rainbow of colors all meant something -- if that was the original Pearson wiring. If it was a previous owner, who knows.

As for running single conductors or the two conductor wire, look at the spaces you are routing through. I like the two conductor (and 3 for AC), but if I'm routing several wires through a constricted place, I may have to use single conductor as it is overall less bulky. Then again, you can only bundle so many wires together without running afoul of ABYC standards (i.e., risking fire) -- know the guidelines!

Books to consider (we had to buy them for trade school and I liked them):

Ed Sherman's Powerboater's Guide to Electrical Systems -- good reference, even for a sailor

Nigel Calder's Boatowner's Mechanical and Electrical Manual (aka the bible!)

Sherman's is shorter and less daunting…ya know, gotta explain things simply to a stinkpotter!

[rw58ph]

Several years ago we had an insurance auditor/surveyor go through the Eagle and required to being the Eagle up to ABYC standards with in 90 days to renew the insurance. 19 electrical standard infractions. The majority of the infractions were additional breakers and fused terminal blocks as wire stacking should not be done. The entire pilot house had to be rewired. I did 80% of the wiring and had a marine electrician check and approve the final installation as the insurance auditor did come back to double check. 60 day and 3+ grand later the Eagle was approved.

So make sure you use large enough gauge wire suitable for marine use, replace according to ABYC standards and have a marine electrician review/ok you work.

[Roy M]

Noreastern, while the others are arguing about wire, I thought I'd go off in a different direction. If you have a computer with a spreadsheet program, things will be a bit easier, though you can do this exercise with a pad of paper and a pencil, to start.

First, since you have a sizeable boat (38' Pearson), you must realize that you will probably want the option to add stuff, at some time in the future, or if you have increased the available number of circuits, a future owner will pay more for your boat.

Write down a list of all the electrical stuff you have, or want for the future. Now look at this stuff and decide what circuit it will be a part of. For example, all cabin lighting on one (or two circuits). I have two lighting circuits on my boat, portside and starboard. That way, if I need to shut off power to one side (or if there is a problem), I can still have enough lighting to avoid working completely in the dark. If you need some help here, use the Blue Sea catalog (http://www.bluesea.com/), which has circuit breaker labels, as a guide. Once you have decided how many circuits you want, then write down, in the spreadsheet, or paper pad, all of the specific lamps or other units that will be powered by that circuit breaker. Now, find out how much current each unit needs (this can be found in a catalog or by shopping at a good marine store). Now, group all units that might be located near one another. For example, all of the galley lamps, the main salon lamps, etc. This is the point where your planning will take a great leap forward.

Having added up all of the current (amps) that would be flowing should you have every unit in the circuit on at the same time (example, all portside lighting units) you will have a figure that tells you how big a circuit breaker is called for. You're not done, though, because the wire the current flows through is subject to the electrical resistance of the size wire and the distance the wire has to travel, from the breaker to the unit, then back to the ground buss.

To avoid having used individual wires to each unit, from the circuit breaker, you need to divide your total units into groups, which will be powered by dual strip busses, metal strips with lots of screws. For example, starting at the electrical panel, where the breaker is located, you will have several busses, located in several parts of the boat. Perhaps one in the galley, one in the main salon, one in the forward cabin, and anywhere else that you have a number of lamps that need wire running in relatively short distances from the buss. The idea here is that current flows from the breaker using a large wire to a buss, via a two-wire cable for the positive and negative sides. This cable can then terminate on the buss, powering both the positive and negative strips, or it can also continue to another buss further away. If you do this, it will result in fewer wires running from the circuit breaker to the individual lamp, and allow a more efficient distribution of adequate power to all units served by the breaker. For example, because you have calculated that you will need 10 amps (all of the lights associated with one buss in the galley) you can the write down the distance the current flows from the breaker to the galley lighting buss. Then you measure the distance for the wire needed to go from the galley lighting buss to the lamp over the stove, and write it down. You do the same with each unit that is fed by the buss.

Now, go to the Blue Sea wiring calculator (http://circuitwizard.bluesea.com/) and begin to determine the wire sizes needed to conduct sufficient electricity from the breaker to the buss that results in less than 3% voltage drop (the result of pushing electrons through the resistance of copper wire). Then you do the same thing for the individual lamp, measuring the distance from the buss to the lamp over the stove, which tells you that a lamp using 2 amps, getting its power from the galley buss, will also be receiving power with less than 3% voltage drop.

What I'm trying to say here is that you want a large wire to feed the buss, and to tap off the buss with smaller wire to the individual units needing power. You want a minimum of large wires running around the boat to their respective busses, which then branch off with smaller wires to the individual lamp. The calculation is done for you by the wire size calculator. You just need to figure where on your own boat, you want to locate the busses. Make it a protected spot, safe from things that might roll or touch the two sides of the buss accidentally (even though you will be covering the busses with a protective cover). Remember, Murphy's Law has not been repealed, nor likely ever will be.

When you have done all of the calculations for all of the circuits on the boat, you are ready for the next step, which you and anyone else following in your footsteps will be thankful in the future. This requires a labelmaker and your spreadsheet. Give each individual circuit a number (example, Portside Cabin Lights is labelled "1"). Under the heading for this circuit, you list all of the individual busses you will have that are powered by that breaker (example, Galley Lights, Main Salon Lights (portside), Head Lights, Forward Cabin Lights). Give each of these busses their own number. Now you are almost done. Give the individual units (lights, in this case) their own distinct number). Now, on the spreadsheet list all of the wires served by the breaker, in numerical order (example, the fluorescent lamp over stove is labelled 01-01-01). The idea is that each wire on the boat is coded individually, telling anyone that the unit is served by a specific breaker, which leads to a specific buss, then to a specific unit.

Once every unit is coded, you are ready to do the task of wiring. Because you have calculated the total current for every lamp drawing power from the breaker, you install the correct breaker at the panel. If you are drawing too much from one breaker, you can consider making two circuits instead, to reduce the size of the breaker (but increasing the number of breakers on the panel). Then, because you have calculated the current to the individual buss (from all the unit served by that buss), you can install a feeder cable to the buss that is adequate for your needs. Then, the same for the individual unit power wiring.

So, starting at the panel, you install a dual buss somewhere inside the electrical compartment for each breaker (if there will be several distributed busses throughout the boat, as in our cabin light example). That way, you have a large wire from the breaker to the panel buss, then smaller cables to the individual busses, then smaller wires to the individual unit. As you begin installing your new wiring, you use the spreadsheet, with its codes, to guide you. You label the wire from the breaker (example,"01") to the panel buss. Then, starting in order, you label each wire going off to its respective buss (example, the wire going to the galley is "01-01", the wire to the forward cabin is "01-05". As you begin to do the actual wiring, you do it in order of the code so that you don't forget anything. And, as you do the wiring, you provide a label for each end of that wire (assuming it's more than a couple inches away). That means that our galley stove fluorescent lamp is labelled "01-01-04) and its code is labelled at both ends of the wire. Then, you can check off the appropriate line on the spreadsheet and be absolutely sure you have done the job.

I make my labels about three inches long, and I provide a name and the code, both on the left margin side of label, so that the label has, on the left side, the name "GALLEY FLUOR at the top, and underneath "01-01-04". Then I strip off the adhesive cover and fold the label in half, over the wire, creating a flag, near the point of attachment to the buss or the lamp. Where things connect to the individual lamp or unit, I use insulated male/female connectors so that I can easily remove the lamp or pump or whatever if it needs service in the future.

I know this seems arduous, but it will ensure you have adequate power to everything that will be served, that anyone can determine what an individual wire connects with, and that a surveyor, inspecting your vessel, will see that you really had your act together. Especially, if you show him your spreadsheet with its indicated current requirements, wiring length and wire sizes. Insurance companies really eat it up, also, assuming they've sent someone who really gets it.

Also remember that you may want to add things in the future, so size your breakers and busses for possible future units, which means adequate cable feeders to the busses.

Sorry this is so long-winded. I built my boat over thirty-five years ago when things were simpler, and I was poorer. I had six DC breakers and 240 amp hours of battery capacity. I now have 16 DC breakers, a 2000 watt inverter, and 740 amp hours of house bank. I needed a system to ensure I did have the correct wiring and breaker sizes for my needs now and in the future.

[Horror Hotel]

It comes down to if you would wire your current house without help? And be confident? If it's no, then leave the job for someone else. That's the simple answer.

[Roy M]

For those that use a wire size calculator a lot, Blue Sea has a free app for your smartphone.

[Cheechako]

Nobody in the business sizes each wire for each appliance. Figure your highest load for "light loads " like lighting, vhf, electronics etc ... just make all those wires that gauge. Likely 14 gauge or maybe 12 gauge. Then there will be just a few things like bilge pumps or other pumps etc, that need larger wire.. likely 10 gage. just make all those the same gauge also. number the ends and pull them through in a bundle. Bob's your uncle.... when in doubt, just go bigger and get on with the project.

[mitiempo]

Originally Posted by Cheechako

Nobody in the business sizes each wire for each appliance.

I agree. The smallest wire I use is 14 gauge, 12 for longer runs on non critical items like lighting and fans. Refrigeration, macerators, and similar items get a larger wire, possibly 10 gauge but I have used 8 gauge on longer runs. Breakers are 15 for all lighting runs with 14 gauge - also the standard loaded breaker on a Blue Seas panel. On a larger boat I like running heavier wire to buses and out from there to each light. 15 amp breakers are still fine for this as long as the max load is under that, the heavier wire giving lower voltage drop. I always use tinned stranded boat cable, available under many brand names of which Ancor is only one. They don't make their own wire anyway, just buy and add their name to it.

The best book I have come across is Charlie Wing's book shown below, second edition. Easy to understand and very up to date.

[Noreastern]

Thanks for all the responses. I must say I feel a little ignorant about wiring after reading them all.

The boat we are refitting was built in 1965 and from what I am reading here is not up to today's standards for wiring. However I must give credit to those guys who designed and installed the wiring back then. Except for one light everything that was installed in 1965 worked until I ripped it all out a month ago. What was I thinking.....

For the seven years we have sailed this boat I have not had any electrical failures on electronic equipment or a dead battery. I am sure some of this was luck but I also believe that keeping things simple as possible helps a great deal.

For wire I usually buy Ancor marine wire from places like Jamestown. 16 gauge seems to be on the skimpy side from what I am reading so most likely will go with 14 gauge. The reason for using one gauge is to keep everything the same. The only long runs are for lights. Distribution panel will be at nav station which is about mid-ship. Besides for lights there will be the power hungry devices of refrigeration five feet across from nav station, auto-pilot about seven feet aft of nav station, radar, stereo and VHF at nav station and bilge pumps located three feet below nav station. Cannot forget, a luxury of a working depth finder to back up the lead line. This will be located on outer bulkhead above nav station.

House batteries are conveniently (unless boat is flooded) located below nav station in the bilge just forward of engine and thus alternator. This may be a 38' boat but will be wired with runs as if she was only 20'.

The thought of using yellow for a positive came from when I re-wired the mast. For the deck/steaming light compo I used three conductor wire inclosed in one case. I thought the colors were red/black/yellow but may have been mistaken on the yellow. Will check today to see what three colors were used.

Guess what I have learned is that I will be using 14 gauge 2 conductor wire (red/black) in single case for most of the wiring and maybe larger for auto pilot and reefer. So simple.

Thanks again for all the input.

[skipmac]

Hi Noreastern,

One more load that might like a larger wire gauge would be electric bilge pumps. A very small maintenance pump might do OK with 14 gauge but I wired my large, emergency pumps with 8 gauge.

Also, Jamestown is a good source but I have found usually a little more expensive than some other sources. If you're in CT I assume you have found Defender in Watertown? Also, really good prices for wire, crimps, electrical tools, breakers and such (and with free shipping) is www.genuinedealz.com

Good luck on the wiring.

Skip