Electrical Leak....Help!

A/C & D/C Wiring, GPS, Radios, etc.
jtalberts
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Joined: Sat Jul 12, 2014 7:30 pm

Electrical Leak....Help!

Postby jtalberts » Mon Jul 14, 2014 10:16 pm

Well my capac reading is at about .75 on the Seacrest. I am in fresh water and the current is at it's normal flow. For some reason, I decided I wanted to jump in and see if I could replace the trim tab anodes with it in the water. I touched the starboard trim tab and I got a good bit of current running through my arm. I did some basic troubleshooting but wasn't able to find out where the issue is. The only thing that we did to get the current to stop flowing was to unplug the shorepower. Even when turning off the AC breakers 1 by 1, I was still able to feel the current. So I have a couple questions, where do I start trying to track this down? Would a DC leak cause the same symptoms and go away when the shorepower is disconnected, or is this pointing to an AC leak because of the shore power? I am looking at the shorepower connectors cabling into the boat and I have more tracing to do. There is a capac Galvonic Isolator on the boat that is NOW hooked up correctly. One of the shorepower connectors was bypassing the GI and going straight into the 120V panel. I had a survey done on this boat and boy does it tick me off that I have to do this again! I went the right direction and thought I wouldn't have to be doing this again. I am just ticked enough I am ready to rip out all the cabling and start over.

Please HELP!
1973 Marinette Seacrest Executive
41x14
Twin Chrysler 340's with Velvet Drive 71C
"Figment"

barkleydave
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Posts: 350
Joined: Sat Jul 12, 2014 6:18 am
Location: Kentucky

Re: Electrical Leak....Help!

Postby barkleydave » Tue Jul 15, 2014 7:10 am

First THIS PROBLEM IS NOT A DC LEAK. This is an AC leak VERY VERY VERY DANGEROUS!!!!

Your CAPAC works on DC and is very small neg. current between the Anode and the Cathode.

First you have an AC leak which going to ground.

1. DO NOT GO INTO THE WATER!
A . Take your volt meter put negative on ground of your AC (you can use the safety ground on one of your outlets. Put the other lead in the water and read the voltage.

For the moment let's assume your shore power connection to the marina and the marina wiring is ok. (often not the case)

B. Your shore power is hooked up and if there is an AC leak you should be able to read the voltage.
C. Now lets assume you have confirmed AC through the meter. (more than a .10th of a volt)
Start disconnecting you AC devices one at a time. Example battery charger (hope it is a marine not automotive) refrig water heater etc. Have a helper monitor the voltage on the meter. If after this there is still voltage then you must assume it is in your electrical internal wiring or.... shore power cord, marina grounding problem etc.

Note a common problem is a bad element on a water heater... or a shorted winding on a battery charger.

Note: make sure your green safety ground wire is properly connected. I have found cases where folks intentionally disconnected the green safety ground on their shore power cable because they thought it was causing galvanic corrosion!

Until you fine and repair the problem I WOULD NOT recommend you plug your boat into AC. This can be fatal if someone is in the water near your boat!

Keep us posted on your findings.

safe boating,

dave
1987 Marinette 29 FB Sedan
Retired Boat Accident UL and USCG trained investigator
Retired USCG Captain

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bill
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Posts: 411
Joined: Sat Jul 12, 2014 7:17 am
Location: Grosse Ile MI

Re: Electrical Leak....Help!

Postby bill » Tue Jul 15, 2014 7:24 am

:idea: The shore power box needs to have a GFI installed. :roll:
Live to boat another day. :)
ALUMINATION
Grosse Ile MI
Located on LakeErie
37' F/B Sedan
1975
Twin 360 Chrysler Marine
Raw water cooled
Hydraulic steering both helms
USCG Master Lic. Retired

Third Owner bill

jtalberts
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Posts: 133
Joined: Sat Jul 12, 2014 7:30 pm

Re: Electrical Leak....Help!

Postby jtalberts » Tue Jul 15, 2014 9:42 am

Pardon the stupidity with a multimeter. I have a reference an node I am using as my lead in the water as my stock multimeter leads were too short. What setting on the multimeter should I have it switched to for measuring? I had it on V~ 200 and I got a reading of 1.12 even with the shore power unplugged.
1973 Marinette Seacrest Executive
41x14
Twin Chrysler 340's with Velvet Drive 71C
"Figment"

barkleydave
Site Admin
Posts: 350
Joined: Sat Jul 12, 2014 6:18 am
Location: Kentucky

Re: Electrical Leak....Help!

Postby barkleydave » Tue Jul 15, 2014 1:50 pm

No anode is used
This is an A .C.voltage test.
Set to AC
1 lead to ground other in the water...





Dave
1987 Marinette 29 FB Sedan
Retired Boat Accident UL and USCG trained investigator
Retired USCG Captain

jtalberts
Aluminum Star
Posts: 133
Joined: Sat Jul 12, 2014 7:30 pm

Re: Electrical Leak....Help!

Postby jtalberts » Wed Jul 16, 2014 8:16 pm

Well I think we have it taken care of. We replaced the shore power adapters so looked at those. The wiring was correct but we noticed there was some flex and bare cable. We replaced the cable and now I don't see any of the issues. Thanks for the help.
1973 Marinette Seacrest Executive
41x14
Twin Chrysler 340's with Velvet Drive 71C
"Figment"

jtalberts
Aluminum Star
Posts: 133
Joined: Sat Jul 12, 2014 7:30 pm

Re: Electrical Leak....Help!

Postby jtalberts » Sun Jul 20, 2014 9:21 pm

Well, as we started to dig through this, we have found that our AC electric is wrong. From what I can guess the 2nd Air conditioner was added to the boat at some point in the past. In order to run both of the units, they added a 2nd 30amp shore power adapter. From all the reading I have been doing, the proper way to do this would be to add a 2nd AC breaker panel as well. Well, I still only have 1 AC panel. I have ordered all the parts for an entirely new AC 120V system for my boat. I am even going as far as installing Isolation Transformers as I am tired of worrying about the shore power screwing up my boat. I will post more details on here as the project goes on.
1973 Marinette Seacrest Executive
41x14
Twin Chrysler 340's with Velvet Drive 71C
"Figment"