Cruisers Forum
 


Reply
  This discussion is proudly sponsored by:
Please support our sponsors and let them know you heard about their products on Cruisers Forums. Advertise Here
 
Thread Tools Search this Thread Rate Thread Display Modes
Old 04-03-2012, 02:11   #16
Registered User
 
Katiusha's Avatar

Join Date: Aug 2011
Posts: 803
Re: Why We Don't Leave Our Boat Plugged In

You can always hand another zinc anode over the side, like "zinc grouper" or "hanging anode".

We have a fish zinc, like the one in this link: Zinc Grouper and hand it up clipping it to the shrouds whenever we're in a marina. It worked wonders to our prop zinc lifetime! And the fish still hasn't corroded to nothing after 3 years.

You can also use a bigger cousin of this fish: http://www.boatzincs.com/hanging_anode_zinc.html if the fish corrodes too quickly.

P.S. Just don't forget to take it down when underway
Katiusha is offline   Reply With Quote
Old 04-03-2012, 02:18   #17
Registered User
 
Katiusha's Avatar

Join Date: Aug 2011
Posts: 803
Re: Why We Don't Leave Our Boat Plugged In

My other half says that as a proper solution you should really get a galvanic isolator. Most likely there is a stray current in the shore's ground, so you want to isolate ship's ground from shore's.

They don't call galvanic isolators "zinc savers" for nothing.
Katiusha is offline   Reply With Quote
Old 04-03-2012, 05:02   #18
Registered User
 
levm's Avatar

Join Date: Jun 2010
Location: St. Maarten & Israel
Boat: Grand Soleill 41 - Gali
Posts: 93
Images: 1
Re: Why We Don't Leave Our Boat Plugged In

You may want to install a galvanic isolator on your ground plug it will let AC go through but will eliminate the DC dripping into your boat and reduce the zincs erosion.
__________________
Sailing together doubles the joy and half the pain
levm is offline   Reply With Quote
Old 04-03-2012, 06:05   #19
Registered User
 
SV Demeter's Avatar

Join Date: Dec 2009
Location: Cruising Eastern Caribbean
Boat: Taswell 49
Posts: 1,199
I hung one of the zinc groupers over the side clipped to a chainplate which is connected. Meter moved a little but not Significantly better when plugged in. Yeah galvanic isolator is probably the way to go but my future plans for this boat don't involve marinas so I may hold off on that expense.
__________________
Ted Reshetiloff
SV Demeter is offline   Reply With Quote
Old 04-03-2012, 06:19   #20
Senior Cruiser
 
GordMay's Avatar

Cruisers Forum Supporter

Join Date: Mar 2003
Location: Thunder Bay, Ontario - 48-29N x 89-20W
Boat: (Cruiser Living On Dirt)
Posts: 49,126
Images: 241
Re: Why we dont leave our boat plugged in

Quote:
Originally Posted by DotDun View Post
I believe any good quality digital meter will work.
http://assets.fluke.com/appnotes/ele...r/B0269b_u.pdf
Indeed; but you still need a (Ag/AgCl) reference electrode.
__________________
Gord May
"If you didn't have the time or money to do it right in the first place, when will you get the time/$ to fix it?"



GordMay is offline   Reply With Quote
Old 04-03-2012, 08:37   #21
Registered User

Join Date: Jun 2007
Location: SW Florida
Boat: FP Belize, 43' - Dot Dun
Posts: 3,823
Re: Why We Don't Leave Our Boat Plugged In

Quote:
Originally Posted by bazzer View Post
Any idea where I can get a Reference electrode ?
for example:

Corrosion Reference Electrode
DotDun is offline   Reply With Quote
Old 07-03-2012, 09:07   #22
Registered User
 
kefroeschner's Avatar

Join Date: Feb 2012
Location: Livermore California, St Petersburg Florida
Boat: Morgan, Ocean Racer, 45'
Posts: 80
Re: Why we dont leave our boat plugged in

I agreee with the two-wire solution. Americans seem to be "ground-obsessed." There is no such thing as "ground," especially on a boat. The water, especially in a marina, is just a big electro-chemistry experiment. Don't participate. Make no electrical connection to anything that might get wet. Treat both wires of AC shorepower (black and white) as HOT. Neither one is "ground" or even "neutral" in any reliable sense. The green wire is used to sense current where there should be none and should be connected to any metal chassis of any electrical device that you might touch but nothing else.
kefroeschner is offline   Reply With Quote
Old 07-03-2012, 12:07   #23
Ike
Registered User
 
Ike's Avatar

Join Date: Oct 2008
Location: Pacific Northwest, USA
Boat: FL12 12 ft rowboat, 8 foot sailing dink, 18 foot SeaRay I/O
Posts: 324
Re: Why We Don't Leave Our Boat Plugged In

You are a physicist and you believe this? How is it then that electrical engineers, electricians, authorities and experts on this subject do not accept your two wire solution? Your solution was what came before the three wire system, and is the reason for electrocutions and fires on boats. It was also the reason for many electrocutions and fires ashore. That third wire is there specifically to provide a path for current back to ground, instead of going through your body. It is used not just on boats but anywhere AC electricity is used. This provides a much higher level of safety.

The only truth in your comment is:
Quote:
Treat both wires of AC shorepower (black and white) as HOT. Neither one is "ground" or even "neutral" in any reliable sense.
Yes they are both hot. And if there is a fault where one or the other is inadvertently connected to a metal casing or metal part of the boat, then the current has no way to get back to ground until someone accidentally touches something that is metal and now HOT!. Without the green wire, it has nowhere to go except through you.

Been there, done that, and fortunately lived to talk about it.
__________________
Ike
"Dont tell me I can't, tell me how I can"
Ike is offline   Reply With Quote
Old 07-03-2012, 12:10   #24
Registered User
 
Celestialsailor's Avatar

Join Date: Nov 2006
Location: Back in Northern California working on the Ranch
Boat: Pearson 365 Sloop and 9' Fatty Knees.
Posts: 10,466
Images: 5
Re: Why We Don't Leave Our Boat Plugged In

The problem with galvanic isolators is when they go out (and they do) it does damage from what I hear.
I think another problem is the common means of bonding the DC ground to the AC ground. If there is fault with the marina wiring or the guy beside you has a cheap 1960's type 2 prong auto motive charger, it is quite possible to cross hot with neutral that way. It will give stray currents a path to less noble metals. If you are bonded this way, try un-bonding AC ground to the DC. Generally it is done at the engine block or in your panel.

As far as the 2 wire solution...Are you nuts? If everyone did that, the whole harbor would be hot enough to cook fish!
__________________
"Life is not a journey to the grave with the intention of arriving safely in a pretty and well-preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming: Wow - what a ride!"
Celestialsailor is offline   Reply With Quote
Old 07-03-2012, 13:01   #25
Ike
Registered User
 
Ike's Avatar

Join Date: Oct 2008
Location: Pacific Northwest, USA
Boat: FL12 12 ft rowboat, 8 foot sailing dink, 18 foot SeaRay I/O
Posts: 324
Re: Why We Don't Leave Our Boat Plugged In

Galvanic isolators do fail. But the current (no pun intended) standard requires them to have a status monitor that alerts the operator to a failure, or they must be a fail safe isolator, meaning they must only fail in the conducting mode. This preserves the integrity of the green wire.

Part of the problem here is that many people do not think of the AC, DC, Bonding and lightning protection as separate systems. To correctly install and understand how it all works one needs to think of them as separate, and only connected together at one place. To add to the confusion, the concept of bonding all metal fittings in contact with the water is still very controversial. That is why some people advocate cutting the green wire. They do not understand how these systems work separately. If you don't want to bond, then don't bond. But don't ever cut the third (green wire) in the AC system. See diagram that shows how AC, DC and Grounding system are connected. Does not include a lightning protection system. http://newboatbuilders.com/images/circuit8.jpg

And I quote:
Quote:
As far as the 2 wire solution...Are you nuts? If everyone did that, the whole harbor would be hot enough to cook fish!
This is why a major part of my boat builders web site is devoted to electrical systems.

One top of all that a lot depends on whether you have a fiberglass, wood, or metal boat. So it can all be rather intimidating. That's why I have always told boat owners and builders, that unless they have a strong electrical background, or anything beyond a 12V DC system, do not DIY you boat's electrical system. Hire an electrical engineer to design it and a certified marine electrician to install it.
__________________
Ike
"Dont tell me I can't, tell me how I can"
Ike is offline   Reply With Quote
Old 07-03-2012, 13:16   #26
Registered User
 
Celestialsailor's Avatar

Join Date: Nov 2006
Location: Back in Northern California working on the Ranch
Boat: Pearson 365 Sloop and 9' Fatty Knees.
Posts: 10,466
Images: 5
Re: Why We Don't Leave Our Boat Plugged In

Personally, I feel my way is the safest...I keep DC separate from AC. Secondly...no bonding. Third, a healthy investment in solar to keep the systems running if I need them to while I'm away from the vessel. Third, I unplug the shore power at my boat. Not just shut it off at the dock breaker. That way the ground is disconnected too. No chance of a hot cross over to neutral which is where the ground is connected at the harbor panel. Lastly hang a grouper over the rail. Not only does it add protection, it gives you a real world look at whats going on in the water. JMHO.
__________________
"Life is not a journey to the grave with the intention of arriving safely in a pretty and well-preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming: Wow - what a ride!"
Celestialsailor is offline   Reply With Quote
Old 07-03-2012, 14:40   #27
Registered User
 
kefroeschner's Avatar

Join Date: Feb 2012
Location: Livermore California, St Petersburg Florida
Boat: Morgan, Ocean Racer, 45'
Posts: 80
Re: Why We Don't Leave Our Boat Plugged In

Ike:

I never advocated cutting the green wire. Read my last sentence. But bear in my mind it's purpose -- to detect current in either AC line from the chassis back to the source. There are several other comments from guys who get it -- the source (or sink) is not some fictitious "ground" -- it is the other end of the power source -- the negative terminal of the battery for instance. If you are connected to shore power your green wire goes back to the source of that shorepower. If you are running on an inverter it goes back to the inverter. The problems that arise result from tying these various sources together (often backwards) by connecting their green (fault sensing) wires together as if they were a common "ground."

Keeping the DC and AC sources separate as Celestial Sailor suggests is sound. I would go further and have nothing connected to shorepower and the local electro-chemistry experiment except my battery charger, with all three wires of course, the shore's green wire connected to the charger chassis and nothing else. Then run everything on the boat from a(n) inverter(s). The green wires of any AC appliances on board go back to the inverter, not to the shore power system.

Lastly, I would note comments from some Europeans who have very little of these problems. They know that the brown and blue are both hot (+ and - 120v, 180 degrees out of phase and that the green (and yellow over there) is a fault sensor, not a "ground."

Finally, connecting anything electrical to the water is just asking for trouble.
kefroeschner is offline   Reply With Quote
Old 07-03-2012, 14:48   #28
Registered User
 
kefroeschner's Avatar

Join Date: Feb 2012
Location: Livermore California, St Petersburg Florida
Boat: Morgan, Ocean Racer, 45'
Posts: 80
Re: Why We Don't Leave Our Boat Plugged In

Oh, one other thing -- you only see three wire plugs (in the US) on things that have a metal case. If the two hot wires (black and white) are completely encased and insulated and there is nothing for them to short to, then the third prong and green wire are considered to be unnecessary. UL thinks so, anyway.
kefroeschner is offline   Reply With Quote
Old 07-03-2012, 15:23   #29
Registered User
 
Celestialsailor's Avatar

Join Date: Nov 2006
Location: Back in Northern California working on the Ranch
Boat: Pearson 365 Sloop and 9' Fatty Knees.
Posts: 10,466
Images: 5
Re: Why We Don't Leave Our Boat Plugged In

One other thing not mentioned yet. It is a good idea to have ground fault outlets on the boat. If something does go wrong on the boat or in the harbor, those babies start popping.
__________________
"Life is not a journey to the grave with the intention of arriving safely in a pretty and well-preserved body, but rather to skid in broadside, thoroughly used up, totally worn out, and loudly proclaiming: Wow - what a ride!"
Celestialsailor is offline   Reply With Quote
Old 07-03-2012, 17:49   #30
Registered User
 
kefroeschner's Avatar

Join Date: Feb 2012
Location: Livermore California, St Petersburg Florida
Boat: Morgan, Ocean Racer, 45'
Posts: 80
Re: Why We Don't Leave Our Boat Plugged In

Oh Yeah
kefroeschner is offline   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Kids In the Cruisers & Sailing Photo Gallery - Is It Just Me? deckofficer Our Community 84 30-11-2012 12:55
Boat Shoes ... jesperrosenberg Atlantic & the Caribbean 12 08-03-2012 16:44
1917 Herreshoff Found in NH Soundbounder General Sailing Forum 2 06-03-2012 07:54
Boat Insurance for the Caribbean wahoo40 Boat Ownership & Making a Living 6 04-03-2012 18:03
Pass the International Boat license in Australia to use it in Europe Le-Blond Rules of the Road, Regulations & Red Tape 15 27-02-2012 21:54

Advertise Here


All times are GMT -7. The time now is 01:02.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2024, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.