Recently our 95' 430 began eating zinks. I couldn't find any thing so I hired a marine electrican. ( the difference between an electrican with marine in is name and a regular electrican I discovered is the hourly rate is abut 2x normal.) He did find a burnt lug on the common on the shore power, and added some additional bonds throughout the boat. We also added a galvanic isolator. He now says the bonding system is great and reads less than 200 mv. Is this less than 200 mv a good reading, if not what should it be?? Thanks in Advance Dick McKee S/V Constellation
- Status
- Not open for further replies.
B
bill walton
don't know but ...
We did the same last year for our 42. It had a Galvanic isolator but it had been improperly installed at the factory. The Electrician configured it properly and installed a bonding cable, about #2, connecting all metal through hulls. My zinc usage went from several per year to one. I could have done the bonding wire myself but I didn't know what was required. After I watched the electrician, I was angry at myself for not investigating further and saving a couple of hundred.
We did the same last year for our 42. It had a Galvanic isolator but it had been improperly installed at the factory. The Electrician configured it properly and installed a bonding cable, about #2, connecting all metal through hulls. My zinc usage went from several per year to one. I could have done the bonding wire myself but I didn't know what was required. After I watched the electrician, I was angry at myself for not investigating further and saving a couple of hundred.
B
Bob
galvanic isolator????
Could you explain the galvanic isolator? Is it recommended that all metal thru-hulls be bonded together into the grounding system? Did you ground everything (engine- rigging etc.) to the common grounding system? Pardon me for asking so many questions but the boating electrical department is not one of my strong suits.
Could you explain the galvanic isolator? Is it recommended that all metal thru-hulls be bonded together into the grounding system? Did you ground everything (engine- rigging etc.) to the common grounding system? Pardon me for asking so many questions but the boating electrical department is not one of my strong suits.
D
Dick McKee
Bob...
The galvanic isolator "insulates" your boat from stray electricity from the dock or boats around you. Your boat may be great, but if someone close has a "dirty" boat it can cause electrolisis on yours. There is a great article in the September issue of Cruising World that explains it. If you dont have the magazine e-mail me a fax # at mckee119@hotmail.com and Ill be glad to send it to you.
The galvanic isolator "insulates" your boat from stray electricity from the dock or boats around you. Your boat may be great, but if someone close has a "dirty" boat it can cause electrolisis on yours. There is a great article in the September issue of Cruising World that explains it. If you dont have the magazine e-mail me a fax # at mckee119@hotmail.com and Ill be glad to send it to you.
B
bob
galvanic isolator - bonding
i've recently gone through the same problem and have added a galvanic isolator to my 40.5...my boat is not bonded...in looking into this, there appear to be 2 religions - those that swear by bonding and those that say it can cause more problems than it solves...being semi-ignorant (and intimidated by the whole topic), i'm an agnostic at this point.... one point i'm clear on ....the galvanic isolator isolates you from other boat/marina eletrical problems to which you are connected through the shore power ac ground wire.... bonding on the other hand relates only to potential corrosion of sea cocks and other metal in the water on your boat...a bonding system must be connected to an underwater zinc, not your boat's ground...nigel calder has a section on bonding in his book...he doesn't subscribe to the bonding philosophy, and his boat is not bonded... i plan to contact the hunter factory to discuss this with them...
i've recently gone through the same problem and have added a galvanic isolator to my 40.5...my boat is not bonded...in looking into this, there appear to be 2 religions - those that swear by bonding and those that say it can cause more problems than it solves...being semi-ignorant (and intimidated by the whole topic), i'm an agnostic at this point.... one point i'm clear on ....the galvanic isolator isolates you from other boat/marina eletrical problems to which you are connected through the shore power ac ground wire.... bonding on the other hand relates only to potential corrosion of sea cocks and other metal in the water on your boat...a bonding system must be connected to an underwater zinc, not your boat's ground...nigel calder has a section on bonding in his book...he doesn't subscribe to the bonding philosophy, and his boat is not bonded... i plan to contact the hunter factory to discuss this with them...
B
Bob
Rigging/Engine Ground???
Is it recommended to have a common ground between the engine, shaft, and the rigging? As I recall, it was recommendedby Nigel Calder.
Is it recommended to have a common ground between the engine, shaft, and the rigging? As I recall, it was recommendedby Nigel Calder.
R
R.W.Landau
Equilizing potentials
The purpose of bonding is to equilize potentials. If static builds in the mast and rigging, it will maintain a different potential than the water around it. I believe this is a lighting magnet. I think this is a good argument for bonding. Thru-hulls are in contact with the water and should not need grounded. If all through hulls and the engine are bonded together, your boat will be creating it's own battery between the metals of the different through hull, rudder shaft, prop, prop shaft,etc. All bonding should be to one point. This includes the rigging. Thus,if you bond electronics and the refrig to one point and the mast and battery negative to another, you have created a loop in the negative wiring that causes a reaction right under your own boat. Bonding between the ac and dc is another matter. The negative battery lead should be(must be! for your safety) bonded to the ground (and only the ground) of the shore power. If there is a short that conducts ac through the dc system, the ac ground will conduct the short without creating a dangerous (less dangerous) shock hazard between the ac and dc systems. It is important to check the marina electric, often to make sure thier gound is working.The negative terminal and the ac ground should be connected directly to the grounding plate (if you have one)or a point of gound your boat is using into the water. The Galvanic isolator should be on the ground wire on the shore side of this connection. The galvanic isolator will not work if something is wrong with the shore power. Test to make sure that the is no current or voltage present in the ground wire. The galvanic isolator will only work if the voltage is less than 1 volt. If it is greater than one volt, you are one of the cells in the marina battery that is eating your boat. Dick, where is he measuring this 200mv voltage? I believe a current reading would be a better indicator. It is the current flow that does the damage. r.w.landau
The purpose of bonding is to equilize potentials. If static builds in the mast and rigging, it will maintain a different potential than the water around it. I believe this is a lighting magnet. I think this is a good argument for bonding. Thru-hulls are in contact with the water and should not need grounded. If all through hulls and the engine are bonded together, your boat will be creating it's own battery between the metals of the different through hull, rudder shaft, prop, prop shaft,etc. All bonding should be to one point. This includes the rigging. Thus,if you bond electronics and the refrig to one point and the mast and battery negative to another, you have created a loop in the negative wiring that causes a reaction right under your own boat. Bonding between the ac and dc is another matter. The negative battery lead should be(must be! for your safety) bonded to the ground (and only the ground) of the shore power. If there is a short that conducts ac through the dc system, the ac ground will conduct the short without creating a dangerous (less dangerous) shock hazard between the ac and dc systems. It is important to check the marina electric, often to make sure thier gound is working.The negative terminal and the ac ground should be connected directly to the grounding plate (if you have one)or a point of gound your boat is using into the water. The Galvanic isolator should be on the ground wire on the shore side of this connection. The galvanic isolator will not work if something is wrong with the shore power. Test to make sure that the is no current or voltage present in the ground wire. The galvanic isolator will only work if the voltage is less than 1 volt. If it is greater than one volt, you are one of the cells in the marina battery that is eating your boat. Dick, where is he measuring this 200mv voltage? I believe a current reading would be a better indicator. It is the current flow that does the damage. r.w.landau
- Status
- Not open for further replies.