Back to ground plates

Hello to All, I am refitting my Cal29 more or less from scratch. To date I have seen a ground connection in the bilge, which is simply an attachment to a very large and rusty eye-bolt (one of two such bolts), and another connection to a through-hull located in the engine compartment a few inches to the port side of the center-line of the vessel. This boat has no engine and will not have one installed. I would greatly appreciate learning what ground plate arrangements you have on your boats, including external plates with through-hull attachments in the cabin. I would like to learn about both AC and DC grounds that you currently use. Thanks in advance, Brad Bates Br… [at] verizon.net

I am not answering your question but rather making a comment about having multiple ground connections to things that go to the water. Some people like to do this and I wanted to offer another opinion on this. As an Electrical Engineer, I think of having two metals in a conductive liquid like salt water as being a battery. The voltage you get depends on how different the two metals are. If they are identical alloys, there is no voltage. All boats are full of such batteries. One of particular interest has zinc as one of the electrodes. In all cases, the battery action is such that one element moves ions to the other and electrons flow the other way. The ions take the metal with them so eventually that electrode is gone. That is why you have to replace your zincs. Anyway, the end of this long story is that if you don't connect a wire between two pieces of metal on your boat, you basically have a battery sitting on the shelf. Bronze as a battery element has a 100 year shelf life. If you connect the two electrodes (through hulls) together, you have a shorted battery. Which do you think lasts longer? Moral, don't bond the metals in your boat together. By the way, my boat (L-36) is wood and the process of the ions and electrons creates hydroxyl ions which eat the inners of the wood. You are left with a honey comb where the wood used to be right around the zinc. I quit "protecting" so much of the metal on my boat because it is easier to replace the metal then the wood. Besides, if you don't bond them, the shelf life is very long and it will last longer than I will and at that point I don't care. Allen On Thu, Jun 11, 2009 at 2:35 PM, sj24brad <Br… [at] verizon.net> wrote: > > > Hello to All, > > I am refitting my Cal29 more or less from scratch. To date I have seen a > ground connection in the bilge, which is simply an attachment to a very > large and rusty eye-bolt (one of two such bolts), and another connection to > a through-hull located in the engine compartment a few inches to the port > side of the center-line of the vessel. > > This boat has no engine and will not have one installed. > > I would greatly appreciate learning what ground plate arrangements you have > on your boats, including external plates with through-hull attachments in > the cabin. I would like to learn about both AC and DC grounds that you > currently use. > > Thanks in advance, > > Brad Bates > Br… [at] verizon.net <Bradley.Bates%40verizon.net> > > >

Brad, sorry I diverted the discussion to lightning. I am also curious as to how one would do AC ground system in a boat with an encapsulated keel. I also note that through-hulls are often not metal. Cheers Charlie Annapolis From: Ca… [at] yahoogroups.com [mailto:Ca… [at] yahoogroups.com] On Behalf Of sj24brad Sent: Thursday, June 11, 2009 5:36 PM To: Ca… [at] yahoogroups.com Subject: [Cal_Boats] Back to ground plates Hello to All, I am refitting my Cal29 more or less from scratch. To date I have seen a ground connection in the bilge, which is simply an attachment to a very large and rusty eye-bolt (one of two such bolts), and another connection to a through-hull located in the engine compartment a few inches to the port side of the center-line of the vessel. This boat has no engine and will not have one installed. I would greatly appreciate learning what ground plate arrangements you have on your boats, including external plates with through-hull attachments in the cabin. I would like to learn about both AC and DC grounds that you currently use. Thanks in advance, Brad Bates Br… [at] verizon.net ------------------------------------ Yahoo! Groups Links

Why not just ground to the shore ground wire? I really wouldn't want the boat next to me connecting any part of the AC system to the water. If it gets screwed up, it frys all the boats in the harbor. When you are under way, you don't need to worry about the shore power ground. Perhaps you are talking about a gen set. In that case, ground to the gen set. Allen On Thu, Jun 11, 2009 at 6:07 PM, Husar, Charlie [USA] <hu… [at] bah.com > wrote: > > > > Brad, sorry I diverted the discussion to lightning. I am also curious > as to how one would do AC ground system in a boat with an encapsulated > keel. > > I also note that through-hulls are often not metal. > > Cheers > Charlie > Annapolis > > -----Original Message----- > From: Ca… [at] yahoogroups.com <Cal_Boats%40yahoogroups.com> [mailto: > Ca… [at] yahoogroups.com <Cal_Boats%40yahoogroups.com>] On > Behalf Of sj24brad > Sent: Thursday, June 11, 2009 5:36 PM > To: Ca… [at] yahoogroups.com <Cal_Boats%40yahoogroups.com> > Subject: [Cal_Boats] Back to ground plates > > Hello to All, > > I am refitting my Cal29 more or less from scratch. To date I have seen > a ground connection in the bilge, which is simply an attachment to a > very large and rusty eye-bolt (one of two such bolts), and another > connection to a through-hull located in the engine compartment a few > inches to the port side of the center-line of the vessel. > > This boat has no engine and will not have one installed. > > I would greatly appreciate learning what ground plate arrangements you > have on your boats, including external plates with through-hull > attachments in the cabin. I would like to learn about both AC and DC > grounds that you currently use. > > Thanks in advance, > > Brad Bates > Br… [at] verizon.net <Bradley.Bates%40verizon.net> > > ------------------------------------ > > Yahoo! Groups Links > > >

I want to say thanks to all of you who responded to this question. Allen's points about how different metals react with salt water and grounding to shore power and a gen set are spot on. And Charlie, no apology needed for me. This is a discussion forum, right? I know just enough about electricity and electronics to be uncomfortable with any assumptions. So please bear with me when I have more to ask on the subject. I just want to be sure that crew, the boat, and me remain safe as I install things! Thanks again, Brad Bates --- In Ca… [at] yahoogroups.com, Allen Edwards <allen.edwards@...> wrote: > > Why not just ground to the shore ground wire? I really wouldn't want the > boat next to me connecting any part of the AC system to the water. If it > gets screwed up, it frys all the boats in the harbor. When you are under > way, you don't need to worry about the shore power ground. Perhaps you are > talking about a gen set. In that case, ground to the gen set. > Allen > > On Thu, Jun 11, 2009 at 6:07 PM, Husar, Charlie [USA] <husar_charlie@... > > wrote: > > > > > > > > > Brad, sorry I diverted the discussion to lightning. I am also curious > > as to how one would do AC ground system in a boat with an encapsulated > > keel. > > > > I also note that through-hulls are often not metal. > > > > Cheers > > Charlie > > Annapolis > > > > -----Original Message----- > > From: Ca… [at] yahoogroups.com <Cal_Boats%40yahoogroups.com> [mailto: > > Ca… [at] yahoogroups.com <Cal_Boats%40yahoogroups.com>] On > > Behalf Of sj24brad > > Sent: Thursday, June 11, 2009 5:36 PM > > To: Ca… [at] yahoogroups.com <Cal_Boats%40yahoogroups.com> > > Subject: [Cal_Boats] Back to ground plates > > > > Hello to All, > > > > I am refitting my Cal29 more or less from scratch. To date I have seen > > a ground connection in the bilge, which is simply an attachment to a > > very large and rusty eye-bolt (one of two such bolts), and another > > connection to a through-hull located in the engine compartment a few > > inches to the port side of the center-line of the vessel. > > > > This boat has no engine and will not have one installed. > > > > I would greatly appreciate learning what ground plate arrangements you > > have on your boats, including external plates with through-hull > > attachments in the cabin. I would like to learn about both AC and DC > > grounds that you currently use. > > > > Thanks in advance, > > > > Brad Bates > > Bradley.Bates@... <Bradley.Bates%40verizon.net> > > > > ------------------------------------ > > > > Yahoo! Groups Links > > > > > > >