[ccriders]

Defender shows four thirty amp isolators made by Guest, Newmar, Pro Mariner and Yandina, costing from $90 to $300. Does anyone have experience with these models or can recommend any one of them. My only AC load is the battery charger, but I've been going through zincs at a rapid pace.
Thanks,
John

 

[VF84Sluggo]

Wondering the exact same thing...hopefully someone will weigh in.

 

[weinie]

Testing A Galvanic Isolator Photo Gallery by Compass Marine How To at pbase.com

 

[eherlihy]

I suggest that you read Nigel Calder's Boat Owner's Mechanical and Electrical Manual for a thorough explanation of what they are, and how they work. They will protect you from other boats when you are on shore power, but they will not protect you from dissimilar metals on you boat.

I have a Prosafe 30Amp unit on my boat, and it seems to work well.

I have also un-bonded all of my through hulls. I don't recommend that anyone else do this.

 

[Anchorbend]

This may help you out.

Yandina Marine Electronics

 

[Maine Sail]

You will want a GI that is considered "fail safe". This means that in the event of a failure you do not lose your ground. While a decent price, the Yandina does not meet the fail safe requirement...

 

[VF84Sluggo]

Very good to know, thanks!

My next question would be, where is the 'best' place to mount the isolator? I'm assuming that there would be room behind the boat's electrical power cb/control panel. I realize this will very much depend upon the layout of the boat, so in my case I'd be doing the install in a Catalina 30.

I did look at the DEI isolator, and the physical size and shape makes it look like finding a good spot for it should not be too difficult.

 

[eherlihy]

Very good to know, thanks!

My next question would be, where is the 'best' place to mount the isolator? I'm assuming that there would be room behind the boat's electrical power cb/control panel. I realize this will very much depend upon the layout of the boat, so in my case I'd be doing the install in a Catalina 30.

I did look at the DEI isolator, and the physical size and shape makes it look like finding a good spot for it should not be too difficult.

I put my GI in line with the main AC wire... Rather than rip out the original cable, I simply cut the jacket, in a convenient place to mount the GI, and spliced the GI into the ground line. Some day I will replace the cable, but for now...

Electrically, the GI is the last thing on the ground wire before the ground circuit leaves the boat (via a SmartPlug).

 

[ccriders]

I suggest that you read Nigel Calder's Boat Owner's Mechanical and Electrical Manual for a thorough explanation of what they are, and how they work. They will protect you from other boats when you are on shore power, but they will not protect you from dissimilar metals on you boat.

I have a Prosafe 30Amp unit on my boat, and it seems to work well.

I have also un-bonded all of my through hulls. I don't recommend that anyone else do this.

I have the Charlie Wing book and use it for reference.
RE: bonding of through hulls. I recently hauled out to re do the bottom. No zincs left at all and discovered pink on the gudgeon and strut. Also that the gudgeon had slight movement. In removing and resetting the gudgeon I found that the bonding cable between the gudgeon and strut (and then to the engine) had corroded and separated.
I'm really trying to figure this out, but find conflicting information.
I have an atomic four connected to a stainless steel drive shaft held by a bronze strut driving a bronze propeller (which also showed some pink). All of this bonded with #6 wire (which was showing signs of corrosion). The pearson bonding diagram (which does not exactly match what is in place) shows chain plates, through hulls, grudgeon and strut bonded to the engine and then to a keel bolt.
The only AC on my boat is the battery charger and any hand tools I might be using. I never leave the shore cable connected more than overnight and go weeks without using it at all. The DC grounding bus is connected to the engine. Any DC leakage should go down the shaft which has two new zincs now. So my concern is what is causing the galvanic action on the grudgeon, strut and propeller and how do I stop it.
One last detail. Two plus years ago I used Petit's zinc anti fouling paint on the strut, shaft and strut. I was pleased with its performance and have used it again. Could this be a contributor to my problem.
And another detail. I sit between two neglected boats that are continuously connected to shore power, but have no knowledge what is going on inside.
I appreciate any help you can give,
John

 

[RichH]

Corrosion Reference Electrode Product Specifications

 

[Waltthesalt]

I made one from plans on-line. Not complicated, just mounting items in a plastic box and connecting wires. Had to mail order the diode bridges. Need to have a heat sink for them e.g. aluminium plate.

 

[eherlihy]

Removing the bonding wire takes the through hull out of the bonding circuit, thereby preventing galvanic corrosion from dissimilar metals that may be electrically connected. This includes your boat, and those near you. However, you are also increasing the damage that may be done to your boat if you are hit by lightning. If you have seawater in the bilge, and it touches these through hulls, then you have created a new circuit to promote galvanic corrosion, without the benefit of lightning protection..