Trouble shooting a hot dock

[Retirement Dream]

Hi. My dock is so "hot" that zincs need to be replaced every other month or so. The harbor isn't real interested in solving the problem so I'm wondering, do any of you know how to trouble shoot a dock to find out where all the extra electricity is coming from and how to make it go away? Any references or ideas will be greatly welcomed. Scott aboard Retirement Dream.

 

[gsc3]

ShockAlert is an in-water detector for stray electricity. See ShockAlert.com for operation and purchase information.

 

[TexasEye]

https://www.usace.army.mil/Portals/2/do ... 130937-857

Might want to make sure your boat isn't causing the problem. One boat with an electrical leak can play havoc on all boats in the Marina. Most states require annual inspections and immediate corrections of electrical leaks at marina's.

 

[SassyRed]

Http://Www.boatus.com/boattech/articles ... rosion.asp


This is a pretty good article discussing typical causes of corrosion. The simple answer is that many causes of corrosion manifest via a current traveling over the shore power ground wire (think of current in a wire like water in a pipe). With a sensitive clamp-on meter you may be able to detect and measure this current. But if you don’t have a galvanic isolator you should get one because it mediates many common corrosion causes. The galvanic isolator prevents or severely restricts low level current flow and thus limits corrosion.

A galvanic isolator probably won’t help if your own boat is leaking current to a ground in your boat. That might be hard to find.

And of course, anodes only work if they are submerged and well connected to the boat ground. No paint on or under, etc. Probably not your issue since your anodes are being eaten.

Good luck

 

[Dale777]

Retirement Dream,

You asked, "...how to trouble shoot a dock to find out where all the extra electricity is coming from and how to make it go away?"

I think a "Corrosion Reference Electrode" is the tool you are looking for. See this link:
https://www.boatzincs.com/corrosion-ref ... specs.html

This is the link to the manual:
https://www.sbmar.com/wp-content/upload ... -Guide.pdf

The problem might be on your boat or with other nearby boats. If the problem is with nearby boats, the best solution is to install a Galvanic Isolator or to leave your boat disconnected from shore power. If you have a solar panel and you do not leave your frig running, the the solar panel will likely keep your batteries charged.

Since the Corrosion Reference Electrode is somewhat costly and requires that you know how to use it properly, it might be best to hire a corrosion expert to test your boat and dock area.

If you decided to do your own testing, check out this video:
https://www.youtube.com/watch?v=NqzWdOAeHG8
and this:
https://www.youtube.com/watch?v=vGehTCw_voI

 

[baz]

Disconnect your shore power cord from the shore power pedestal each week and only reconnect it once per 24 hrs each week. Your batteries can last a week without the shore power connection so long as you power off everything on the boat.

I had this problem and was having to replace underwater anodes every 3 months. I now only connect 24 hrs each week and my underwater anodes go for 9 to 12 months when they've reached 50% or less. I can do this as I live but a few minutes from my slip.