Shore GFCI trips when plugging in boat - Page 2 - SailNet Community

   Search Sailnet:

 forums  store  


Quick Menu
Forums           
Articles          
Galleries        
Boat Reviews  
Classifieds     
Search SailNet 
Boat Search (new)

Shop the
SailNet Store
Anchor Locker
Boatbuilding & Repair
Charts
Clothing
Electrical
Electronics
Engine
Hatches and Portlights
Interior And Galley
Maintenance
Marine Electronics
Navigation
Other Items
Plumbing and Pumps
Rigging
Safety
Sailing Hardware
Trailer & Watersports
Clearance Items

Advertise Here






Go Back   SailNet Community > On Board > Gear & Maintenance > Electrical Systems
 Not a Member? 
  #11  
Old 05-31-2013
Senior Member
 
Join Date: Jan 2010
Location: Boston, MA
Posts: 525
Thanks: 2
Thanked 1 Time in 1 Post
Rep Power: 5
rmeador is on a distinguished road
Re: Shore GFCI trips when plugging in boat

There are a lot of ideas here that I'll need to test over the weekend. Ebs001, the inverter automatically switches between pass-through of shore power and inverting depending on whether it senses shore power. The switch is effectively instantaneous so none of the electronics on the boat know anything is amiss -- it's great during a blackout. When shore power resumes, it verifies the stability for about 15 seconds before switching back to pass-through mode.
__________________
1979 Gulfstar 37 Laissez Faire
Reply With Quote Share with Facebook
  #12  
Old 05-31-2013
ebs001's Avatar
Senior Member
 
Join Date: May 2006
Location: Ottawa, Canada
Posts: 2,145
Thanks: 5
Thanked 21 Times in 19 Posts
Rep Power: 9
ebs001 is on a distinguished road
Re: Shore GFCI trips when plugging in boat

Quote:
Originally Posted by rmeador View Post
There are a lot of ideas here that I'll need to test over the weekend. Ebs001, the inverter automatically switches between pass-through of shore power and inverting depending on whether it senses shore power. The switch is effectively instantaneous so none of the electronics on the boat know anything is amiss -- it's great during a blackout. When shore power resumes, it verifies the stability for about 15 seconds before switching back to pass-through mode.
That automatic switching may be your problem. GFCI specs indicate that they should trip in less than a nanosecond which may be enough to catch the auto switch. It's to bad you are not able to connect to that GFCI receptacle again because it's possible that you will get it to trip no matter what load you have on and it's not the charger at all.
Reply With Quote Share with Facebook
  #13  
Old 05-31-2013
Vasco's Avatar
Warm Weather Sailor
 
Join Date: Sep 2006
Location: Toronto
Posts: 985
Thanks: 0
Thanked 6 Times in 6 Posts
Rep Power: 9
Vasco is on a distinguished road
Re: Shore GFCI trips when plugging in boat

Check your hot water tank. Even with the hot water turned of it would trip the shore GFI. Cleaned the contacts to the heating element and all was fine.
__________________
Rick I
Toronto in summer, Bahamas in winter.

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Reply With Quote Share with Facebook
  #14  
Old 06-01-2013
eherlihy's Avatar
Learning the HARD way...
 
Join Date: Jan 2007
Location: Boston Area
Posts: 3,557
Thanks: 114
Thanked 64 Times in 63 Posts
Rep Power: 8
eherlihy will become famous soon enough
Re: Shore GFCI trips when plugging in boat

Quote:
Originally Posted by rmeador View Post
I do have an oscilloscope (and a logic analyzer, not that it's useful for this -- I'm an electrical engineer!). Are you suggesting that the absence of a voltage between ground and neutral will indicate a ground fault? I can't quite figure out what you're getting at. There is always a voltage present between those two lines any time a circuit is under load due to the resistance in the wires. Any other boats on my dock drawing power will result in me seeing that voltage even if I am not drawing anything. I suppose if those lines are shorted inside my boat, I might not see a voltage. Or do you mean when inverting only (no shore power)?
When the inverter/charger is OFF, and the boat is out of the water, the potential voltage difference between neutral and ground should be 0VAC, 0VDC. When it is on, the potential voltage should be ~110VAC and 0VDC. Again, assuming that the boat is out of the water.
__________________

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

USCG Licensed OUPV Captain, ASA 101/103/104/105 Certified Instructor - Also certified in Recreational Marine Electrical Systems
Reply With Quote Share with Facebook
  #15  
Old 06-02-2013
ebs001's Avatar
Senior Member
 
Join Date: May 2006
Location: Ottawa, Canada
Posts: 2,145
Thanks: 5
Thanked 21 Times in 19 Posts
Rep Power: 9
ebs001 is on a distinguished road
Re: Shore GFCI trips when plugging in boat

Quote:
Originally Posted by eherlihy View Post
When the inverter/charger is OFF, and the boat is out of the water, the potential voltage difference between neutral and ground should be 0VAC, 0VDC. When it is on, the potential voltage should be ~110VAC and 0VDC. Again, assuming that the boat is out of the water.
If the boat is plugged in the potential voltage between neutral and ground should be 0 VAC as the neutral is the grounded conductor. This does not change whether or not the boat is in the water.
Reply With Quote Share with Facebook
  #16  
Old 06-02-2013
eherlihy's Avatar
Learning the HARD way...
 
Join Date: Jan 2007
Location: Boston Area
Posts: 3,557
Thanks: 114
Thanked 64 Times in 63 Posts
Rep Power: 8
eherlihy will become famous soon enough
Re: Shore GFCI trips when plugging in boat

I'm allowing for galvanic current which may be a factor when the boat is in the water. The OP did say that this was only an issue when the boat was on the hard. The OP did not say if he had any form of ground isolation.
__________________

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

USCG Licensed OUPV Captain, ASA 101/103/104/105 Certified Instructor - Also certified in Recreational Marine Electrical Systems

Last edited by eherlihy; 06-02-2013 at 09:46 AM.
Reply With Quote Share with Facebook
  #17  
Old 06-02-2013
ebs001's Avatar
Senior Member
 
Join Date: May 2006
Location: Ottawa, Canada
Posts: 2,145
Thanks: 5
Thanked 21 Times in 19 Posts
Rep Power: 9
ebs001 is on a distinguished road
Re: Shore GFCI trips when plugging in boat

Quote:
Originally Posted by eherlihy View Post
I'm allowing for galvanic current which may be a factor when the boat is in the water. The OP did say that this was only an issue when the boat was on the hard. The OP did not say if he had any form of ground isolation.
Regardless, the potential between ground and neutral on the A/C side should always be zero. When plugged-in to shore power the neutral and ground must not be connected on the boat since they are connected at the source in this case the marina service but when he's connected to his inverter the neutral is grounded which is proper.

The O/Ps problem occurs with a GFCI receptacle. When he is on the hard he only had power available from a GFCI and while at the dock he is on power not protected by GFCI. Thus the ground fault only showed up when he tried to connect to a GFCI protected circuit. Without being connected to a GFCI protected circuit it will be difficult to solve the problem.
Reply With Quote Share with Facebook
  #18  
Old 06-04-2013
eherlihy's Avatar
Learning the HARD way...
 
Join Date: Jan 2007
Location: Boston Area
Posts: 3,557
Thanks: 114
Thanked 64 Times in 63 Posts
Rep Power: 8
eherlihy will become famous soon enough
Re: Shore GFCI trips when plugging in boat

Based on this;
Quote:
My boat is on the hard right now for a bottom job. The yard provides power in the form of a standard household 15A outlet with GFCI. Whenever I plug my boat into it, either the GFCI trips or my main AC breaker trips.
I have assumed that this is a new problem which manifests itself only when on the hard.

I agree that the AC neutral and AC Ground should NOT be connected on the boat, and that AC Neutral should not be tied to the bonding circuit. This does not mean that it is true. If they are, it could explain the behavior.
__________________

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

USCG Licensed OUPV Captain, ASA 101/103/104/105 Certified Instructor - Also certified in Recreational Marine Electrical Systems
Reply With Quote Share with Facebook
  #19  
Old 06-04-2013
Senior Member
 
Join Date: Jan 2010
Location: Boston, MA
Posts: 525
Thanks: 2
Thanked 1 Time in 1 Post
Rep Power: 5
rmeador is on a distinguished road
Re: Shore GFCI trips when plugging in boat

Thank you all for your input... I still haven't had a chance to do any real testing with your recommendations. I do not have any kind of ground isolation (which I assume would be the same as a galvanic isolator?). My AC and DC grounds are both tied to the engine block, and I believe the thru-hull bonding system is also tied to the engine block -- the zincs are on the prop shaft, at any rate, so I figure there must be an electrical connection there somewhere. Neutral is not connected to ground except inside the interver when it is actually inverting (supposedly).
__________________
1979 Gulfstar 37 Laissez Faire
Reply With Quote Share with Facebook
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

 
Posting Rules
You may post new threads
You may post replies
You may post attachments
You may edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Water heater popping GFCI jetdrvr393 Gear & Maintenance 5 09-06-2011 03:57 PM
GFCI Outlets brokesailor Gear & Maintenance 2 04-09-2011 04:52 PM
GFCI / Galvanic Isolator Problem thekeip Gear & Maintenance 10 01-09-2008 06:57 PM
good boat for the long run with eventual very long trips in mind AmeriCdn Boat Review and Purchase Forum 2 07-24-2007 01:05 PM
Need boat for long coastal trips Swiftgruve Boat Review and Purchase Forum 1 08-18-2004 07:10 PM


All times are GMT -4. The time now is 05:52 AM.

Add to My Yahoo!         
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
SEO by vBSEO 3.6.1
(c) Marine.com LLC 2000-2012

The SailNet.com store is owned and operated by a company independent of the SailNet.com forum. You are now leaving the SailNet forum. Click OK to continue or Cancel to return to the SailNet forum.