Re: [Amel Yacht Owners] Re: Prop Shaft Electrolysis


I think that what you are saying is right, Eric, but not when the A/C breakers are off, right?  I think the power is coming from somewhere other than the 220 panel.

I'm thinking that the power to the A/C pump is coming from a relay box somewhere that powers the pump when any of the A/C units is turned on.  My Climma info says there should be one for multiple unit installations.  Does anyone know where that relay box is located on the boat?

It's curious that I have 120VAC between either brown or blue and ground (and the bonding system), when the A/C breakers are off, but no voltage between brown and blue.  When the AC breakers are on, I get 240 between brown and blue and the pump works as it should.

I just don't understand electricity well enough to surmise why I'm seeing what I'm seeing.

If anyone knows where the relay box is for the AC pump, that seems like a good place to start.

As always, thanks for your input.
SM 243

On Dec 1, 2015, at 8:20 AM, sailormon kimberlite@... [amelyachtowners] <amelyachtowners@...> wrote:



You should get 110 volts between the red and ground and 110 volts between the black and the ground. The ground and the white neutral should be the same, as the ground is connected to earth somewhere in the marina.

Fair Winds


Kimberlite Amel Super Maramu #376



From: amelyachtowners@... [mailto:amelyachtowners@...]
Sent: Tuesday, December 01, 2015 8:07 AM
To: amelyachtowners@...
Subject: Re: [Amel Yacht Owners] Re: Prop Shaft Electrolysis



Hi Bill,

Thanks for your thoughts.


I'll look at the plug again, but I'm sure it's wired correctly.  I'll also check the pedestal...I think I should find 120VAC between the red and white posts, and between the black and white posts, and 240VAC between the red and black posts.  Should I find voltage between the red or black and ground?


The voltage is still there with the water heater disconnected, so I doubt it has anything to do with that.  It could be that it's significant that the breakers for the water heater and the forward A/C on the 220 panel are adjacent to each other???


6 months ago I added a galvanic isolator between the switch that chooses generator 220 over shore power 220.  That only affects the ground wire, so I don't  think that is going to be the problem.


I have a 110VAC->220VAC transformer that isn't in play when connected to 200V 50A shore power.



SM 243


On Dec 1, 2015, at 3:28 AM, 'Bill & Judy Rouse' yahoogroups@... [amelyachtowners] <amelyachtowners@...> wrote:




I think that you have two issues. Heating element and wrong wiring.I agree with Eric that there is leakage between the green yellow A/C wire and one of the hot wires. And it also sounds like exactly what has happened to several others when the power cord head is wired wrong in the US. Carefully look at this: 

and this: 


A few things that have not been discussed so far in this thread:

  1. When the heating element needs replacing, it will not continually throw a ground fault. In the beginning of a failure, tiny holes develop in the heating element that allow water inside only when it becomes very hot and the water around it is very hot. You probably need a heating element replacement if it has been 3 or more years since you replaced it.
  2. Do you have any devices ON (connected) while all of the breakers are off such as an isolation transformer? If so, look at it for incorrect wiring.
  3. I am thinking that the wiring from shore power plug through to the 220VAC panel is faulty, or maybe the pedestal is wired wrong.


BeBe 387


On Tue, Dec 1, 2015 at 5:32 AM, Kent Robertson karkauai@... [amelyachtowners] <amelyachtowners@...> wrote:


I am on a U.S. 220v 50 amp pedestal.  The plug is wired as you suggested, leaving the white lug unused.
I know that U.S. 220AC is comprised of two 110AC legs.  I'm wondering, since the voltage between the brown wire and the bonding system is almost exactly half of the 244 v AC, is it possible that one leg of the shore power is touching the bonding system somewhere?  That wouldn't explain the 72vAC I see when running the generator disconnected from shore power.


I also looked for AC current using the reference electrode in the water and the bonding system and got 0 VAC connected to shore power and with all A/C and the water heater breakers turned on.  I don't know if that is even a legitimate test.




On Nov 30, 2015, at 8:17 PM, kimberlite@... [amelyachtowners] <amelyachtowners@...> wrote:


Hi Kent,

If you are plugged into a 50 amp US outlet at the dock i assume you did not hook up the white lug in the plug to anything.


I believe the brown wire should go to the red lug and the blue to the black lug. the yellow green to the green lug.


If I am not mistaken you will still have about 10 volts between the ground and the power lugs in the plug--as the ground and the white neutral are essentially the same.


I think somewhere on your boat there is leakage between the green yellow A/C wire and one of the hot wires.


I am doing this from memory as I am not near the boat.


sm 376 kimberlite.


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