Ground plane/plate and Bonding

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honeybadger

Senior Member
Joined
May 20, 2012
Messages
194
Location
USA
Vessel Name
HoneyBadger
Vessel Make
1990 Harkers Island Trawler Typical wooden hull with a Carolina flare and no deadrise at the stern
When we gutted the old trawler it was a electrical mess, All new A/C wire and all new D/C Now i was looking at the ABYC and NMMA standards and they are different from what i am being told. A/C ground Not netural but the Ground , I am reading this needs to be hooked to the D/C ground ? Also on the bottom of the boat i have about a 12X12 plate with a Zinc the one through bolt had a wire that had broken at some point . What and where should this have been hooked, I have a SSB radio and there is loads of ways to bond the ground for a ground plane for it, From the plate under the boat all the way to hooking the stainless toe rail using it as a bond/ground plane ! Any pratical information that worked for anyone would be Great as i am pretty overloaded with conflicting information at this point.
 
When we gutted the old trawler it was a electrical mess, All new A/C wire and all new D/C Now i was looking at the ABYC and NMMA standards and they are different from what i am being told. A/C ground Not netural but the Ground , I am reading this needs to be hooked to the D/C ground ? Also on the bottom of the boat i have about a 12X12 plate with a Zinc the one through bolt had a wire that had broken at some point . What and where should this have been hooked, I have a SSB radio and there is loads of ways to bond the ground for a ground plane for it, From the plate under the boat all the way to hooking the stainless toe rail using it as a bond/ground plane ! Any pratical information that worked for anyone would be Great as i am pretty overloaded with conflicting information at this point.


I know getting SSBs to work on boats is part art... part science...

That said... read all you can...and pick the brains of someone who has installed a bunch of them on similar boats...ground planes can be as simple as hooking up your bonding system but often it doen't work well.

Yes the A/C green and DC (yellow or black) buss bars are tied together and so is the bonding system (bilge green wire tying all exposed metal together)...and all are tied into the engine block (usually). This is NOT true for metal boats that are set up a bit differently...
 
If I am reading this right you have 3 questions with the word bond. First the ABYC recommends the AC ground, AC neutral and DC ground be connected together (bonded) to the ships ground for AC safety reasons. The second part is the wire on the plate. Be sure the plate on the bottom of your boat is zinc and not bronze. Normally the zinc is located on the transom. On the bottom it could be a dynaplate. We'll get to that in a minute. You have a wooden boat and most of the ideas for bonding for electrolysis purposes will result in a argument between sides. At a minimum you need a zinc plate of some size bonded back to the ships ground. Where that wire connects between is where the argument will begin on a wooden boat. Your decision here needs to come from a qualified shipwright not from an electrician. Third if the plate on the bottom of the boat is bronze it is a dynaplate and is meant to attach the ground from your tuner to form the ground plane for your radio with copper foil. I would look at the KISS Counterpoise ground plane system and forget ground plane issues forever.
 
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If I am reading this right you have 3 questions with the word bond. First the ABYC recommends the AC ground, AC neutral and DC ground be connected together (bonded) to the ships ground for AC safety reasons. The second part is the wire on the plate. Be sure the plate on the bottom of your boat is zinc and not bronze. Normally the zinc is located on the transom. On the bottom it could be a dynaplate. We'll get to that in a minute. You have a wooden boat and most of the ideas for bonding for electrolysis purposes will result in a argument between sides. At a minimum you need a zinc plate of some size bonded back to the ships ground. Where that wire connects between is where the argument will begin on a wooden boat. Your decision here needs to come from a qualified shipwright not from an electrician. Third if the plate on the bottom of the boat is bronze it is a dynaplate and is meant to attach the ground from your tuner to form the ground plane for your radio with copper foil. I would look at the KISS Counterpoise ground plane system and forget ground plane issues forever.

I don't believe AC neutral is connected to ground shipside...only shore side..

And also the dynaplate is usually bonded too.
 
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I don't believe AC neutral is connected to ground shipside...only shore side..

Great Catch Sneed!!!! The AC neutral is not connected to ground on the boat. Brain Fart!!!!:facepalm:

As for bonding the dynaplate it's like bonding any metal connected to the hull on a wooden boat. It's way over my pay grade!:D
 
I don't believe AC neutral is connected to ground shipside...only shore side..

Great Catch Sneed!!!! The AC neutral is not connected to ground on the boat. Brain Fart!!!!

I would have to do some research to be sure, but I believe the AC neutral is supposed to be connected to the ground on the boat when on inverter or generator power (only). They are supposed to be connected together at the point of service. On shorepower, that would be at the marina's panel. On inverter or generator power, that would be at the inverter or generator.

Again, I would have to look it up, but a galvanic isolator should be installed.
 
I would have to do some research to be sure, but I believe the AC neutral is supposed to be connected to the ground on the boat when on inverter or generator power (only). They are supposed to be connected together at the point of service. On shorepower, that would be at the marina's panel. On inverter or generator power, that would be at the inverter or generator.

Again, I would have to look it up, but a galvanic isolator should be installed.

yes inverters/gensets should have their neutrals grounded when in operation and should break that connection when not.
 
The plate on the bottom of your boat is a DynaPlate and not a zinc. This is part of the ground plane for the SSB. There should be a lug on the auto tuner and a wide flat copper strip should run from the tuner to the DynaPlate since it's installed. here is a post on our HF radio install, The Trawler Beach House: Is It Hard To Install A Single Side Band Radio? and some additional info that might help you with that, and here is some info on grounding, Grounding . At this point I would add that if you are not TOTALLY sure you have the experience and know how for an electrical installation that you get professional help. This is not a task that should be taken lightly and one that can have consequences from minor to catastrophic. If you insist on tackling this your self, get a copy of Nigel Calder's Boatowners Electrical. So far the fact that you are unable to sort out the correct advise tells me you probably should not do a major rewire on your own. Also keep in mind that ABYC is a standard and not a requirement. There are safe ways to do an installation that are not ABYC standard. With a start from scratch install, following ABYC as much as is practical is the best way to go. Chuck
 
Pro Boat builder , issue 100 will have all the info on checking and grounding an AC system.
 
Capn Chuck has it all right & has said all you need to know, including correctly identifying the dynaplate and its use.
 
Yes guys thanks for the input lucky for me there is a Yacht Builder about 3 blocks from here. Went over and talked to the electrical person, Said the same hook the Ground of the AC to the DC Ground Bonding bar then it hooks to the engine block and the same contact point to the Metal plate with the Zinc attached and through bolted on the hull. Also the SSB he gave me 4 options of how he creates a ground plane and also said every boat is different with the antenna matching . Also his words were " do not bond the through hulls on a wooden boat" The shoe that runs the keel and past the end of the rudder it has 3 zinc locations along with the rudder zinc and the shaft zinc. So i think its a go on most systems,
 
Yes guys thanks for the input lucky for me there is a Yacht Builder about 3 blocks from here. Went over and talked to the electrical person, Said the same hook the Ground of the AC to the DC Ground Bonding bar then it hooks to the engine block and the same contact point to the Metal plate with the Zinc attached and through bolted on the hull. Also the SSB he gave me 4 options of how he creates a ground plane and also said every boat is different with the antenna matching . Also his words were " do not bond the through hulls on a wooden boat" The shoe that runs the keel and past the end of the rudder it has 3 zinc locations along with the rudder zinc and the shaft zinc. So i think its a go on most systems,
Go back and ask this person why he doesn't recommend installing a galvanic isolator between the shore power ground and the boat's DC ground.

Galvanic Isolator Explained

Galvanic Isolator Data Sheet

http://yandina.com/acrobats/GalvOwnManual.pdf
 
There is a Galvanic isolator in line, Sorry i didn't explain that he ask a few questions and even gave me a list of ones that would work well for me, We walked into the stock room and he had maybe 10 new ones in stock they use for the boats they build showing me what they look like and did explain. I have known this yacht builder years from highgschool and reconnected with him after retirement and moving back here. His current project has blown my mind its a sport fisher with IPS pods/ jackshafts to place the V-8 450hp cats mid ships, Hull was built over a frame with 3 layers of 1/4 ply running other directions then layer over layer of cloth and glass, The fwd area under deck , He has a CNC router that cut each beam to size then they added 2X2's to the top and bottom of the beams and they are every 12 inches back to where the salon starts. Amazing combo of machine and man.
 

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