WARNING, Fresh water swimming & shorepower

[Anonymous 121765]

To all my fellow boaters,

Last year here in Florida, three children were electrocuted while swimming off the back of their boats in FRESH water in what is termed ESD.

The culprit is AC shore power connections. If having your boat plugged-in, freshwater can & will be a killer. Spring & Summer are rushing at us now so, vigilance should be a top priority in protecting oneself & your loved ones.

This is luckily not a problem in saltwater, that being said, freshwater can & will be a killer if allowed.

Here are a few links to better explain the dangers lurking. Please take the time to read & protect yourselves. There is no reason for anyone especially a child to die.

http://www.boatus.com/seaworthy/magazine/2013/july/electric-shock-drowning-explained.asp

http://www.boatingwithdawsons.com/boating-articles/major-harbour-danger-electric-shock.html

http://www.cedtechnologies.com/blog...igation-risk-for-freshwater-facilities-owners

http://www.qualitymarineservices.net/electric_shock_drowning_incident_list.html

PLEASE, take every precaution....

CR

 

[dlandersson]

You mean "if not done properly, marina's with shore power can create deadly situations"?

 

[Brian D]

This is a good time to bring up this video again.

http://www.youtube.com/watch?v=XDf2nhfxVzg

and this one

https://www.youtube.com/watch?feature=player_embedded&v=dcrY59nGxBg

 

[fstbttms]

This is luckily not a problem in saltwater...

Boy, that is a dangerous statement. While most ESD deaths occur in freshwater, ESD can happen in saltwater too. As someone who earns his living swimming around in saltwater marinas, I unplug every boat I work on.

 

[Johnb]

You did a good thing raising this topic. Even if, when done right, power may be safe, why take the risk.

 

[Maine Sail]

I see and measure AC leakage with shockingly high % numbers in terms of plugged in boats....

In fresh water it takes approximately 0.1A or 100mA to kill a human being. Here we have AC leakage, going somewhere, most likely into the surrounding water. This is 19 times the lethal amount to kill a human in fresh water and this level is likely lethal in salt water too....... Ouch!!

 

[Maine Sail]

I see and measure AC leakage with shockingly high % numbers in terms of plugged in boats....

In fresh water it takes approximately 0.1A or 100mA to kill a human being. Here we have AC leakage, going somewhere, most likely into the surrounding water. This is 19 times the lethal amount to kill a human in fresh water and this level is likely lethal in salt water too....... Ouch!!

A show of hands..

Question: How many of you actually have AC GROUND/GREEN WIRE bonded to DC GROUND on-board your boats..?

Answer: 100% should have AC GREEN & DC GROUND bonded on-board the vessel

 

[dparilla]

Answer: 100% should have AC GREEN & DC GROUND bonded on-board the vessel

Am I correct in assuming that a connection at the on board negative bus is sufficient (and correct?) The AC ground wire passes through a galvanic isolator enroute the onboard panel, then the AC ground connects to the DC negative bus which grounds to the engine block with a 4/0 wire?

 

[Maine Sail]

Am I correct in assuming that a connection at the on board negative bus is sufficient (and correct?) The AC ground wire passes through a galvanic isolator enroute the onboard panel, then the AC ground connects to the DC negative bus which grounds to the engine block with a 4/0 wire?

Yes, usually for a 30A service a #10 green wire jumps between AC GREEN bus and DC NEG/GROUND bus..

Easiest check is usually behind AC/DC panel. Just test for continuity between AC GREEN & DC NEG bus...