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Shore Power

Started by Dick, December 24, 2013, 07:31:09 AM

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Dick

 Can anyone tell me how I can hook-up my 2005 23/IV to shore power? In addition to a power cable, will I need some sort of electrical adapter to connect to the boat's electrical system? Also, can I add 12v outlets to power or charge phones, iPads, PCs and the like?
Anyone providing advice please keep in mind that my electrical knowledge on a scale of 1 to 10 is about -5, so please keep it simple.
Thanks and happy holidays.

brackish

Dick,

Do you have a panel that includes an AC section such as below?  If so that is half the battle. Does it have a main breaker and places for additional breakers such as this one does?  If not you will have to add them.



Now, do you have this marine shore power outlet somewhere on your boat.  Mine located on the starboard side outside the coaming.  If not you will have to add same.



Then, if you don't have one, you will have to add an 110V duplex GFIC outlet such as this.



then of course you need a 30AMP shore power cord long enough to reach your dockside power source.

and yes you can add 12 volt outlets to charge up various stuff.  Mine is located above the panel on the teak riser plate of the top companionway step, but you can put it anywhere convenient.  You can just see the bottom edge of mine on the first picture, very top right side.

All of this actually on a 2005 CP23 IV.  If you need additional coaching will be glad to help.  PM me if more details needed.



skip1930

#2
Wow, not asking too much.

The easiest thing~ is to assign the job to a professional boat yard. I know big $$'s.
The second thing~ is punching additional mounting holes for plug-in sockets in my factory fiberglass.
The third thing~ boating is to get away from that darn telephone. [sorry].
Nothing like piece and quiet. I have electronics in a solar cell, chart plotter, radio-am-fm-CD-vhs, speed/depth but rarely turn them on.
Makes me a hippo-crit.  ???

I'm sure the correct information is published in books and on line.
For me I wouldn't do any electrical work other then 12 volts D/C and note that under the perfect conditions 12 volt welding and fire still can occur.  

Never 120 volt A/C ... Liability insurance comes to mind as too many deaths have occurred in harbors where stray electricity from a boat with incorrect grounds have electrocuted swimmers or dinghy sailors with hands in the water.

skip.

-->" How much electricity is lethal? AC current flow of around 100 milliamps (mA) of AC current will put the heart into fibrillation and death will likely follow within seconds. But lesser amounts of electricity, say, 15- 30 mA, will create muscle paralysis, and even the best swimmers will be drowned. Note that most local law enforcement investigators don't have the technical background to recognize an ESD accident and there is no post-mortem evidence available to coroners to ascertain whether electricity was involved in a drowning. It is highly likely that there are many "drowning" victims who were actually electrocuted. " <--





brackish

Quote from: skip1930 on December 24, 2013, 08:42:42 AM
Wow, not asking too much.

The easiest thing~ is to assign the job to a professional boat yard. I know big $$'s.
The second thing~ is punching additional mounting holes for plug-in sockets in my factory fiberglass.
The third thing~ boating is to get away from that darn telephone. [sorry].
Nothing like piece and quiet. I have electronics in a solar cell, chart plotter, radio-am-fm-CD-vhs, speed/depth but rarely turn them on.
Makes me a hippo-crit.  ???

I'm sure the correct information is published in books and on line.
For me I wouldn't do any electrical work other then 12 volts D/C and note that under the perfect conditions 12 volt welding and fire still can occur.  

Never 120 volt A/C ... Liability insurance comes to mind as too many deaths have occurred in harbors where stray electricity from a boat with incorrect grounds have electrocuted swimmers or dinghy sailors with hands in the water.

skip.




Skip, no more difficult or dangerous than doing 110 house wiring which I've done hundreds of times. You use the same type Romex only marine grade.  With regard to liability, about 90% of boats that stay in the water at the Marinas I've used have shore power.  The liability for maintaining the continuous ground is with the marina, not the boat owner. As long as your internal ground circuit is properly done which is easy and your shore power cord is proper, there will be no problem.   And I've never heard of an electrocution from stray current coming from a boat. I've often heard and have experienced rapid deterioration of anodes from minor stray current.  Research and elaborate for us.

It is sure nice to plug into shore power for my charger to maintain my batteries and to be able to use AC tools devices at dockside.

Jon898

#4
With respect to the statement that a boat wiring is "no more difficult or dangerous than doing 110 house wiring", that's not quite the whole story.  There are nuances to boat wiring that can catch the unwary, and boat wiring really needs to follow the ABYC standards which are not the same as the regular house building codes.  Since 2010, those have required an ELCI (Equipment Leakage Circuit Interrupter...a different piece of equipment from a GFCI) to guard against Electric Shock Drowning (ESD).  While ESD is not an issue in salt water, it is very real in fresh water and is thought to potentially be an issue in brackish water depending on the salinity.  There is more information on this at http://www.boatus.com/seaworthy/magazine/2012/october/Raising-Awareness-About-Electric-Shock-Drowning.asp and http://www.boatus.com/seaworthy/magazine/2013/july/electric-shock-drowning-explained.asp

This is not to say you cannot do your own 120V shore power installation, just be aware that there are differences between a good boat installation and a good home installation.  The actual work is pretty much "plug-and-play", you just have to have the right parts in the right order.

cas206

Some useful info here.  Thanks.  Although I won't be adding shore power to my CP-16, I will be replacing the inadequate DIY system in my Pilot Cutter.  (plus this is a nice distraction from the holiday madness).


atrometer

For a cheap short term solution that was suggested to me on this board get a "jump starter".  Most all have 12V outlets, some 110V,usb ports, inverters, compressors, trouble lights, etc.  An over night charge on one of these lasts a long time charging phones, etc.  About $150 or so.  I have one on my CP16 and running/anchor lights which I'll probably never use are all C, D, AA, AAA batteries - even a back up for my hand held VHF.  KISS   

brackish

Quote from: Jon898 on December 24, 2013, 09:56:33 AM
With respect to the statement that a boat wiring is "no more difficult or dangerous than doing 110 house wiring", that's not quite the whole story.  There are nuances to boat wiring that can catch the unwary, and boat wiring really needs to follow the ABYC standards which are not the same as the regular house building codes.  Since 2010, those have required an ELCI (Equipment Leakage Circuit Interrupter...a different piece of equipment from a GFCI) to guard against Electric Shock Drowning (ESD).  While ESD is not an issue in salt water, it is very real in fresh water and is thought to potentially be an issue in brackish water depending on the salinity.  There is more information on this at http://www.boatus.com/seaworthy/magazine/2012/october/Raising-Awareness-About-Electric-Shock-Drowning.asp and http://www.boatus.com/seaworthy/magazine/2013/july/electric-shock-drowning-explained.asp

This is not to say you cannot do your own 120V shore power installation, just be aware that there are differences between a good boat installation and a good home installation.  The actual work is pretty much "plug-and-play", you just have to have the right parts in the right order.

Hmm, don't think I said it was the "same" as house wiring nor that the same code applied, I said it was no more difficult or dangerous (the actual process of wiring).  I stand by that.  I also stand by the liability statement, I think from all the articles you have referenced the problem has been with the dock wiring not the boat and I think that is most of the problem.  Thanks for the info on the ELCI, my boat was wired before the standard was changed and I did some of the work myself, may upgrade just because.  My marina, and most I think have a strict no swimming policy at the docks and there are many good reasons for that.  Additionally, my boat has no conductive material to the water, however that is not the case with an inboard.

skip1930

#8
Brackish no offence but.

" Skip, no more difficult or dangerous than doing 110 house wiring which I've done hundreds of times "

That's why before an 'Occupancy Permit' can be issued in Wisconsin, a new house needs to be inspected.
The guy who fills our vending machines at work and built his house told me about his denial of permit in Green Bay, Wisconsin because his handrails going down stairs to his basement were two inch's too low. Moving in was delayed. Corrected. And a new appointment to be inspected had to be made.

A professional builder working off of approved house plans from an architect probably would have put the hand rails in there correct location. I suppose the electrics go through the same scrutiny. Having said that let me say, I know nothing about electricity though I build motor starter panels using mechanical starters or PLC's.

" The liability for maintaining the continuous ground is with the marina, not the boat owner. " Tell that to the parents of a dead child out for a swim. Anyone can take anyone to court for any reason. Liability; a boat rolls into an anchorage [not a marina] and sits there on it's own power. Or plugs into a dock. And bingo. A heart stops.

Side Bar: The inventor of the ground fault circuit interrupter [GFCI] was a contractor who installed in-ground swimming pools in Florida with underwater lights and became tired of having his clients electrocuted before they finished paying for the pool. Honest ... I was swimming in a hotel's pool and got close to the light and felt the tingle of electricity.

I'm researching aquatic deaths by electrocution with BoatUs and The Ensign. [Referenced above] One moment.

skip.  






brackish

Quote from: skip1930 on December 24, 2013, 04:24:48 PM
" Skip, no more difficult or dangerous than doing 110 house wiring which I've done hundreds of times "

That's why before an 'Occupancy Permit' can be issued in Wisconsin a new house needs to be inspected.
The guy who fills our vending machines and built his house told me about his denial of permit in Green Bay, Wisconsin because his handrails going down stairs to his basement were two inch's too low. Moving in was delayed. Corrected. And a new appointment to be inspected had to be made. A professional builder working off of approved house plans from an architect probably would have put the hand rails in there correct location. I suppose the electrics go through the same scrutiny.

" The liability for maintaining the continuous ground is with the marina, not the boat owner. " Tell that to the parents of a dead child out for a swim. Anyone can take anyone to court for any reason. Liability; a boat rolls into an anchorage and sits there on it's own power. Or plugs into a dock. And bingo. A heart stops.

The inventor of the ground fault circuit interrupter [GFCI] was a contractor who installed in ground swimming pools in Florida with underwater lights and became tired of having his clients electrocuted before they finished paying for the pool.

I'm researching aquatic deaths by electrocution with BoatUs and The Ensign. One moment.

skip. 


Skip, I've owned three houses, two of them brand new but all built by professional builders who had to have them inspected before occupancy.  In each of them I found significant and often dangerous flaws in the wiring and plumbing, things that would not meet the code, that I've had to correct myself.  Just because it is not your profession does not mean you can't do it right.  Certainly you have to do the research. 

In the non OEM marina yard work I think it is even worse.  I think you have about a fifty-fifty chance of getting someone as conscientious our own MacGyver/Jason to do your work and some of the work I've seen done in that other fifty percent is just awful.  Certainly, I'll continue to do it myself and know it is done right.

If you are suggesting that anyone can be sued for any affront, I certainly agree.  I does not matter who did the work, you are in the line of fire if you own the boat.  And with regard to telling the parents of the child, that's poppycock.  I can't do anything about what the marina does, I'm almost never there.  If their system is flawed, while I am sad about a fatal outcome, I am not liable.

What I'm suggesting is that shorepower as in any electrical system should be done correctly and maintained properly, no matter who does it, and that hiring a "professional" doesn't always get you there.




skip1930

#10
A Preventable Dockside Tragedy

By Kevin Ritz

We were a live-aboard family with three active children at a fresh-water marina on a tributary of the Willamette River near Portland, Oregon. Other kids were already swimming in the cove because it was that kind of day— hot and lazy. This was a common practice by adults as well as children during the warm summer of 1999.
Lucas Ritz: 1991 - 1999

Our sons Ian, age 10, and Lucas, age eight, asked to swim with their friends. Permission was granted, subject to close adult supervision by parents including their mother, a graduate nurse. The boys were both wearing Type II life jackets, so it was great fun and presumably safe to play in the water. Our children were schooled in aquatic safety. Being young professional people, my wife, Sheryl, and I had taken every precaution we could for peace of mind in a water environment.

On the inside of the dock, the kids were having a great time floating down with the river current on an inner tube. Lucas moved away from the others toward his mother, who was keeping pace on the dock with the children's water activity. As he approached the ladder to get out of the water, he let out a loud gasp, immediately rolling onto his back in his life jacket, apparently unconscious. Sheryl yelled to the other kids to help him and jumped into the water herself.

As the kids approached Lucas, they felt a slight tingly sensation in the water and immediately backed off. Upon hitting the water downstream from Lucas, Sheryl's extremities went numb and she experienced extreme difficulty moving her limbs, which, at the time, she attributed to fear. Somehow, Sheryl managed to pull Lucas to the dockside where others assisted in getting him onto the dock.

I arrived moments later after hearing the commotion and, along with another onlooker, started giving him CPR, which we continued until the paramedics took over approximately 15 to 20 minutes later. Our beloved Lucas was pronounced dead at 6:30 p.m. at Portland's Emanuel Hospital. One moment he was laughing and playing—an instant later, his short life was over, leaving our hearts broken forever.

As parents we suffered agonies of "how did this happen?" This question then turned into "why did this happen?" We relived every moment trying to sort out what we did or didn't do. It was not until the next morning that we were able to start unraveling the pieces of the mystery. The first assumption was that he drowned. However, he was wearing the best life jacket money could buy, which kept his face out of the water even though he was unconscious. He was pulled from a floating position only moments after rolling onto his back and CPR was started immediately. Also, at no time during CPR could we detect a heartbeat and his color was good. Neither of these observations would indicate drowning.

As Sheryl was telling me what had happened, she said she had never been so fearful in her life as to have her extremities tingle and go numb to the point where she could hardly move while in the water. Ian then related to me for the first time that he also felt a tingling as he approached his brother. Upon hearing all this it seemed clear to me that he did not drown, but that somehow, some way, AC electricity was present in the water where the kids were swimming. Our Lucas had been electrocuted.

I then called the County Coroner's office, requesting an autopsy if they had not already done so, because knowledge of the circumstances and common sense pointed to electrocution, not drowning. They argued that there were no burns on his body. I pointed out that Lucas had been in an electrolytic solution, which eliminated the resistance of the skin (ordinarily skin resistance results in burns when an individual is electrocuted on land). To my complete horror, they responded that they would not know how to test for something like that.

I told them that testing was not difficult and that I was going to test the water in the area. I then called the local Sheriff 's Department and left a message telling them my suspicions. With my digital voltmeter, I went to the area where Lucas had been, put the negative lead to a ground, dropped the positive lead into the water, and immediately got AC voltage. I notified the Sheriff 's Department, reporting what I had found. They agreed to send out some deputies while I called in an electrician to confirm my suspicions. He arrived later that morning, tracing the electricity to a powerboat that was in the area where the kids had been swimming.

Concerns about liability soon unleashed a stream of other investigators, all of whom were suddenly interested in determining the source of the current. The local utility company wound up sending a team. The owner and manager of the marina arrived. More deputies were called.

Meanwhile, the electrician and I continued our investigation, focusing on the powerboat. We found a 12V wire lying on top of an AC wire, which had gotten hot enough to melt its own insulation and that of the hot (black) AC wire. This put 120V AC into the entire ground system of the boat, including the engines and propellers. This, coupled with lack of an AC safety ground, forced the voltage and electrical currentinto the surrounding water.

Fresh water is not a good electrical conductor; therefore the AC was unable to reach ground at a sufficient current to trip the breaker. Because of its high salinity, the human body is a much better conductor of electricity than fresh water. (Saltwater is more conductive than the human body, which explains why electric shock deaths have not occurred in saltwater.) As Lucas approached the ladder, he passed into the field of AC current and, for a brief moment, completed the circuit to ground. His heart was stopped instantly; the insidious path of electrical current took the life of our son.

With my digital voltmeter, I went to the area where Lucas had been, put the negative lead to a ground, dropped the positive lead into the water, and immediately got AC voltage.

At first we considered this a freak accident— a unique set of circumstances that just happened to us. But this event completely changed my life and my focus. I was determined to understand how this could happen and to do everything I could to keep it from happening again. I did not want anyone else to suffer the pain we had suffered. With the collaboration of my business partner, Andy Tufts, I wrote a couple articles for The American Boat and Yacht Council (ABYC), describing the accident and the actions that I have taken to create public and professional awareness of the problem, to provide education and a better understanding of the concepts involved, and to encourage the following of the ABYC standards and the use of ground fault-type devices onboard boats and in marinas.

I determined to enhance my own knowledge so that I would have a solid understanding of the workings of AC currents in freshwater environments. Andy and I have done that using many different avenues, not the least of which was ABYC. We are now both ABYC Master Technicians. Also, the thrust of our marine business changed significantly from emphasis primarily on sales to one concentrating on keeping boats electrically safe using ABYC standards. Our business motto became "Safer Boating Begins With A Safe Boat." On-line, I also started checking out freshwater drownings with the suspicion that many were possibly electrical current related.

Much has happened in the years since and all of it good. The awareness of "electric shock drowning" as a serious freshwater issue has significantly increased. A USCG-funded ABYC grant implemented by Capt. David Rifkin and James Shafer has greatly added to the understanding of how AC current behaves in fresh water. The truth is that most people electrically shocked in fresh water, unlike my son, are drowned. This is because of skeletal muscle paralysis caused by low levels of AC current using the body as part of its return path to its source. This is what Sheryl experienced when she jumped into the water to rescue Lucas. That she didn't drown or get electrocuted was due to the voltage gradient of the electrical current from its source. She entered the water farther from the faulty boat leak than Lucas. Depending upon several bodily factors, a range of say 15 to 30 milliamps (mA) of AC current will create muscle paralysis, and the drowning of even good swimmers is the result. An AC current flow of around 100 mA will put the heart into fibrillation, and death will likely follow within seconds. This is a very serious problem, but it is preventable.

First and foremost, no one should go in the water at a marina. Signs should be posted on every pier warning people to stay out of the water. But, since not everyone will read this article, and since people often ignore signs, (as happened in the case of 19-year old girl in 2005), or may fall into the water accidentally, the only certain cure is to have GFCI-type devices installed on boats that would automatically interrupt the flow of electricity in the case of a fault. There have been at least 60 needless fatalities and 100 unwarranted casualties from freshwater electrically induced faults. The solution in the future may be ELCI's (see sidebar).

The unfortunate reality is that currently there is no post-mortem evidence available to coroners to ascertain whether electricity was involved in a drowning. Nor do most law enforcement personnel have the technical skills or tools to investigate this type of accident. This lack of knowledge, training, and tools leads to questions about how many deaths have occurred due to faulty wiring on boats. Some time after Lucas's death, two Multnomah County River Deputies and I conducted a random sampling of 50 boats in three freshwater marinas in the Portland area. We found 13 boats leaking potentially lethal electrical current into the water. A ratio of 26 percent of faulty boat wiring leads one to wonder if the number of reported electrical deaths in fresh water is only the tip of the iceberg. If you have any doubts about your boat, it should be inspected by an ABYC-certified technician. Do not depend on an electrician with experience only on land. Let's boat safely and save lives. For more information, contact Kevin Ritz at KevinRitz@gmail.com.
The Long-Term Solution:
Equipment Leakage Circuit Interrupters (ELCI)
Lucas's death will not have been in vain if my efforts and involvement with ABYC have played some small part in the creation of a new ABYC E-11 standard that would require the installation of an Equipment Leakage Circuit Interrupter (ELCI) device on boats (already required by code for land-based damp environments such as bathrooms, kitchens, hot tubs, etc.). In our situation, if the 120V AC ground wire had been bonded to the metal components on the boat (i.e. the negative side of the battery), the energizing of the 12V DC system with the 120V AC would have most likely tripped off the shore power breaker, severing electrical current flow. Or, if a Ground Fault Circuit Interrupter (GFCI) breaker had been installed by the marina ahead of the boat's shore power, even 10 mA of current would have tripped it. So, bottom line—if the boat had been properly wired with an ELCI device or the marina placed a GFCI in front of the shore power cord, our son would still be alive today.

Once adopted and implemented on a vessel, the ELCI device, along with ABYC E-11 compliance, coupled with other pertinent ABYC electrical standards, will significantly reduce the odds of an electrically induced death because of an onboard wiring problem. Following standards will not only keep people on the boat electrically protected, but those in the water around the boat will be safe as well. After the accident, GFCI breakers were installed on each of the marina's shore power distribution points. The only problem has been with new people coming to the marina who have tried to bypass the GFCI because their boats have electrical faults and they're tired of resetting breakers.

My business partner and I did extensive research into this issue and have conducted seminars for law enforcement personnel and local, national, and international marine investigators. We also serve as a resource for several agencies if there is a suspicion that electricity might be a factor in a drowning. Our intent is to set up a web site giving technical information on the functioning of electrical currents in fresh water. If this information had been available to us, we would not be still grieving the loss of our son. If this story doesn't say anything else, understand that a relatively simple fix could have prevented years of pain.
       <img height="1" width="1" border="0" alt="" src="http://googleads.g.doubleclick.net/pagead/viewthroughconversion/1071933959/?frame=0&random=1387928996061&cv=7&fst=1387928996061&num=1&fmt=1&guid=ON&u_h=768&u_w=1366&u_ah=728&u_aw=1366&u_cd=24&u_his=1&u_tz=-360&u_java=true&u_nplug=2&u_nmime=4&frm=0&url=http%3A//www.boatus.com/seaworthy/tragedy/default.asp&ref=http%3A//www.boatus.com/seaworthy/magazine/2013/july/electric-shock-drowning-explained.asp" />

MacGyver

I have read on this, and have extensive knowledge (big surprise, I know....) in doing house wiring, and boat wiring and do both regularly.
I am unable to comment at this time due to a very sudden family death, and I am right now so tired but I wanted to get my mind off of things before my head hit the pillow. I plan to weigh in on this in the next few days.

I am aware of both the drownings, etc and how the effect is from boats to water, stray current, etc.
We actually test for stray current, although I think it is odd. (explain that later)

Anyway, Ill be back in a few days on this, but for sure had to say that Brack is right (from what I have skimmed through so far) that it honestly is a easy thing to do, and to do it properly.

I will get back on this after I have thoroughly read everyones things so as not to offend anyone.

Mac
Former Harbor Master/Boat Tech, Certified in West System, Interlux, and Harken products.
Worked on ALL aspects of the sailboat, 17 years experience.
"I wanted freedom, open air and adventure. I found it on the sea."
-Alaine Gerbault.

Rahn


brackish

I couldn't get Skips link to work, but found the article.  Despite it being very long, I would suggest everyone who has a boat in the water with shore power or around other boats with shore power or dock power to sit through the 1:23 long utube done by Kevin.  It is very enlightening.  It made me realize that:

There are many problem boats and problem docks that have the potential to do great harm.
Most of the problems emanate from really bad junk wiring or in some cases really old technology.
Doing it right is not hard at all, but just because you do it right doesn't mean that your power provider at the dock did it right or your neighbors did it right.
It is very easy to see if you have a problem, a little more difficult to see if a problem exists from other sources.

My conclusion is simple.  Part of my own plan is to put my clamp on, which gathers dust 99.9% of the time in my shop, in the dock box, and take the 10 seconds per visit to clamp it on and check for a less than neutral condition with my shore power cord drawing peak load.  Might check a few of my neighbors while I'm at it.

Do the engineering to consider changing  the system to ELCI with isolation transformer which I think will be a relatively simple and not too costly process.  Hoping I can get an ELCI main that will fit my current panel.

Overkill, perhaps for a boat that has no inboard and is never plugged in with the outboard in the water, with no other conductive material in the water.  Certainly recommended for an inboard of any type.

http://www.cruisingworld.com/how-to/systems/preventing-electric-shock-drownings

I responded to this post because unlike others, I have the exact same model boat as the OP and already have everything that he is interested in as the factory would do it.  Consequently, I know the locations, paths, and can provide both pictures behind the panel and a schematic if he wants to proceed, either as a DIY or to seek professional help.  After consideration of all other posts to the thread and watching Kevin's video, I'm more convinced that it if done properly to current ABYC standards it will not be problematic nor will the job be terribly difficult.  I hope the direction this thread has taken has not frightened him from the project if it is something that he wants. 

Salty19

I would say if you rate yourself as a -5 on a scale from 0-10, and want a simple answer to a very complicated subject,  to not even consider adding 120v functionality yourself.  Too dangerous..you do not want to be zapped by 30 amps of shore power..lethal and worst and darn painful at best or start a fire.

But first things first, you have to understand what you want out of the system.  Do you want 120v power at anchor?  Or just at the dock?  Or under sail? Or all the above?  What do you want to operate? Where do you want to operate it?  For how long do you want it to operate for?  What other items do you want to operate together?  What about the future?  Do you think you'll add items to be used, the amount of time you want them on, and where you'll want them operate?  This opens up cans worms after worms-anything you change will affect your design. So you really gotta get it right up front, or you'll be redesigning it later on much to your chagrin.

Basically you have to answer these questions, and several others to come up with the outcomes you want. Depending on what you want out of it will define what has to get put into it.   Then you need to know what items are needed to fulfill the design and how to make them function reliably in a marine environment.  And this needs to be safe for years, not just after you toggle the first switch and declare success. Adding a simple cigarette-style outlet is a whole lot different than integrating the shore power with your 12V ship power.   

I would say let us know your goals before taking any advice or doing anything. 

In my opinion, I would get a professional beyond much of anything involving adding a cigarette lighter style outlet.    Doesn't sound you like you know a lot about electricity, and that's usually where the stories of fires and electrocutions come from.   I'm not trying at all to be insulting.  Just concerned about your safety
"Island Time" 1998 Com-pac 19XL # 603