If someone could help!!! Got two different boat docks with the same problem..One has a 120 volt line run to apole at the water edge and a GFI receptacle at the pole to connect the dock wiring.. The other has a 240 volt line run to a 2 circuit w/main breker panel and then a GFI breaker supplying the dock power...AT times when someone is in the water an touches the metal dock platform they receive a "tingle". Bothe docks have been checked for correct polarity, have been grounded, and the GFI circuits never trip. Does anyone have a solution Thanks Virgil
Boat dock wiring
- Thread starter vab5594
- Start date
- Status
- Location
- Bremerton, Washington
Re: Boat dock wiring
Get an qualified electrician in to look things over for you.
Turn off main breakers, each and then both. See if problem goes away....
The GFCI trips at 4-6 mA. There may be a low level of current below the trip point that is easily felt in the water.
What does the wiring look like? Old?
Get an qualified electrician in to look things over for you.
Turn off main breakers, each and then both. See if problem goes away....
The GFCI trips at 4-6 mA. There may be a low level of current below the trip point that is easily felt in the water.
What does the wiring look like? Old?
- Location
- Lockport, IL
- Occupation
- Retired Electrical Engineer
Re: Boat dock wiring
The problem might be aboard one or more boats at this dock, or even at a nearby dock. Almost any boat can throw current into the water. The amount of current depends on the service connection, the equipment ground connection, the presence or absence of an isolation transformer, the degree of bonding of external metal parts, and the chemical nature of the metals in contact with water. My first piece of advice is this: If while you are standing at the dock, there is any boat within your field of vision with a power cable from the shore line, don?t allow anyone to swim near the dock. It does not take much of an added push to turn a ?tingle? into a fatal shock. My second piece of advice is to find an electrician with specific experience in marinas and boat docks.
The problem might be aboard one or more boats at this dock, or even at a nearby dock. Almost any boat can throw current into the water. The amount of current depends on the service connection, the equipment ground connection, the presence or absence of an isolation transformer, the degree of bonding of external metal parts, and the chemical nature of the metals in contact with water. My first piece of advice is this: If while you are standing at the dock, there is any boat within your field of vision with a power cable from the shore line, don?t allow anyone to swim near the dock. It does not take much of an added push to turn a ?tingle? into a fatal shock. My second piece of advice is to find an electrician with specific experience in marinas and boat docks.
- Location
- Bremerton, Washington
Re: Boat dock wiring
A ground rod will not solve this problem at all.
Charlie is correct and I had not picked up on the boat side of the issue.
A ground rod will not solve this problem at all.
Charlie is correct and I had not picked up on the boat side of the issue.
brian john
Senior Member
- Location
- Leesburg, VA
Re: Boat dock wiring
You need to find the source of the current. Test the GFI's just because they're installed doesn't mean they work or are wired properly. Check for net currents, on all feeders and branch circuit wiring. If this does not seem to be the source of the problem then try turning off the power to the docks and see if the problem goes away. Don't sacrifice any swimmers; try utilizing a gauss meter at the dock or measuring voltage between the dock and the ground (GEC), neutral and phase conductors of the electrical supply. Use an O’scope check for voltage waveform be sure to check for AC and DC. Check neutral to ground voltage at various points through out the distribution system, with loads on the system the neutral to ground voltage should rise slightly the further you get from the main service(properly wired system, types of loads, distances will effect this) If voltage rises then starts to fall you are close to, a neutral that is grounded downstream of the service. Test the wiring for insulation failure (megger). Verify all wiring between the dock and the main service.
This is not necessarily the order I would complete the troubleshooting, but it is a start. If I think of anymore I’ll email you. KEEP SWIMMERS OUT OF THE WATER.
You need to find the source of the current. Test the GFI's just because they're installed doesn't mean they work or are wired properly. Check for net currents, on all feeders and branch circuit wiring. If this does not seem to be the source of the problem then try turning off the power to the docks and see if the problem goes away. Don't sacrifice any swimmers; try utilizing a gauss meter at the dock or measuring voltage between the dock and the ground (GEC), neutral and phase conductors of the electrical supply. Use an O’scope check for voltage waveform be sure to check for AC and DC. Check neutral to ground voltage at various points through out the distribution system, with loads on the system the neutral to ground voltage should rise slightly the further you get from the main service(properly wired system, types of loads, distances will effect this) If voltage rises then starts to fall you are close to, a neutral that is grounded downstream of the service. Test the wiring for insulation failure (megger). Verify all wiring between the dock and the main service.
This is not necessarily the order I would complete the troubleshooting, but it is a start. If I think of anymore I’ll email you. KEEP SWIMMERS OUT OF THE WATER.
brian john
Senior Member
- Location
- Leesburg, VA
Re: Boat dock wiring
Inquiring minds like to know what was the final outcome with this issue?
Inquiring minds like to know what was the final outcome with this issue?
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