Reply
 
Thread Tools Search this Thread Display Modes
 
Old 10-09-2020, 10:13 PM   #1
Guru
 
oscar's Avatar
 
City: Bethlehem, PA
Country: United States
Vessel Name: Lady Kay V
Vessel Model: 1978 Hatteras 53MY
Join Date: Oct 2015
Posts: 832
Check those shore power connections!

Helped a buddy move his boat today for haul out. He couldn't unplug one of the 30A shore power cords from the boat end, it was stuck. Several tools and a half hour later I had it all apart. It had gotten hot and plastic had melted and fused things together.

The wiring showed significant corrosion. So, that creates resistance which in turn causes heat, as well a voltage drop and then the amps go up to meet the wattage demand and keep the two A/C's (in his case) running.

He got close to a fire there. And, this is where a LOT if not most of the boat fires start.

So check those plugs and make sure they are not overheating!
__________________
Advertisement

__________________
Experience is a cruel teacher.... first it gives the test. Then it gives the lesson.
oscar is offline   Reply With Quote
Old 10-09-2020, 11:11 PM   #2
Guru
 
Comodave's Avatar
 
City: Au Gres, MI
Country: US
Vessel Name: Never Say Never
Vessel Model: President 41 DC
Join Date: Jul 2015
Posts: 9,313
That is exactly why we went to Smart Plugs on our shore power cords.
__________________

__________________
Boat Nut:
If you are one there is no explanation necessary.
If you arenít one, there is no explanation possible.
Comodave is online now   Reply With Quote
Old 10-10-2020, 06:44 AM   #3
TF Site Team
 
Bacchus's Avatar
 
City: Seneca Lake NY
Country: US
Vessel Name: Bacchus
Vessel Model: MS 34 HT Trawler
Join Date: Nov 2014
Posts: 4,134
Oscar
Its been awhile since I checked the stats but its interesting that more electrical boat fires are due to DC than AC. It goes against what many, myseld included, would think. I dont know but might guess there are more folks messing with DC systems that don't really know marine electrical and ABYC guidelines. Likely they figure its only 12V what can go wrong?
Here's a recent Boat US summary... DC about 3X the # of AC
https://www.boatus.com/seaworthy/mag...boat-fires.asp
No argument that boat inlet it worthy of frequent checks and good practices. And if a cord end looks suspect change the boat inlet at the same time. Both go bad and one bad end can damage a new mating one.
__________________
Don
2008 MS 34 HT Trawler
"Bacchus"
Bacchus is online now   Reply With Quote
Old 10-10-2020, 06:51 AM   #4
Guru
 
City: Seaford Va on Poquoson River, VA
Country: United States
Vessel Name: Old Glory
Vessel Model: 1970 Egg Harbor 37 extended salon model
Join Date: Jan 2016
Posts: 2,217
I wonder how many drop their cord ends in the water, then try to dry it and simply plug it back in. If it falls in the water you must rinse it out with fresh, and shake it out. I have accidently dropped it at least twice in 20 years. I bought my boat 20 years ago and the cord was old then, but still in ok shape, it does not get hot when used.

My typical amp draw is under 10 amps when there, and if I run ac and something else, it can approach 20 amps, but I dont live at the boat, so that does not happen often. So most of the time the only draw is the AC charger and fridge, so about 2 - 3 amps max all the time
sdowney717 is offline   Reply With Quote
Old 10-10-2020, 07:49 AM   #5
Guru
 
psneeld's Avatar
 
City: AICW
Country: USA
Vessel Name: Freedom
Vessel Model: Albin 40
Join Date: Oct 2011
Posts: 22,152
DC caused fires probably lead the stats because looking at total numbers, the boats with AC systems are few and far between.....even many of the smaller AC equipped boats have simple systems and many in cooler climatse don't have power hogs like air conditioners and are pulled out of the water before needing heat.
psneeld is online now   Reply With Quote
Old 10-10-2020, 08:24 AM   #6
Guru
 
oscar's Avatar
 
City: Bethlehem, PA
Country: United States
Vessel Name: Lady Kay V
Vessel Model: 1978 Hatteras 53MY
Join Date: Oct 2015
Posts: 832
Quote:
Originally Posted by Comodave View Post
That is exactly why we went to Smart Plugs on our shore power cords.
While they are without doubt an excellent product, if they connect to marginal boat wiring, as was the case on my friend's boat, they won't make any difference.

Don't know the stats of AC vs DC calamities, but I disagree with the statement that "Boats with AC systems are far and few between." Every boat in my marina has a yellow umbilical to the shore power pedestal and other marinas are similar.

People want, and have, A/C, often multiple, heat, microwave/convection ovens, water heaters, large battery chargers and increasingly cook with electricity.
__________________
Experience is a cruel teacher.... first it gives the test. Then it gives the lesson.
oscar is offline   Reply With Quote
Old 10-10-2020, 09:01 AM   #7
Guru
 
City: Rochester, NY
Country: USA
Vessel Name: Hour Glass
Vessel Model: Chris Craft Catalina 381
Join Date: Aug 2019
Posts: 2,243
Quote:
Originally Posted by oscar View Post
Don't know the stats of AC vs DC calamities, but I disagree with the statement that "Boats with AC systems are far and few between." Every boat in my marina has a yellow umbilical to the shore power pedestal and other marinas are similar.

Don't forget to account for the multitude of boats that are trailered and either have no A/C power or never get plugged in.
rslifkin is online now   Reply With Quote
Old 10-10-2020, 09:04 AM   #8
Guru
 
psneeld's Avatar
 
City: AICW
Country: USA
Vessel Name: Freedom
Vessel Model: Albin 40
Join Date: Oct 2011
Posts: 22,152
Quote:
Originally Posted by oscar View Post
While they are without doubt an excellent product, if they connect to marginal boat wiring, as was the case on my friend's boat, they won't make any difference.

Don't know the stats of AC vs DC calamities, but I disagree with the statement that "Boats with AC systems are far and few between." Every boat in my marina has a yellow umbilical to the shore power pedestal and other marinas are similar.

People want, and have, A/C, often multiple, heat, microwave/convection ovens, water heaters, large battery chargers and increasingly cook with electricity.
So you think nationwide the majority of boats in the US are even in marinas?
psneeld is online now   Reply With Quote
Old 10-10-2020, 09:09 AM   #9
Member
 
Steve1.0's Avatar
 
City: Hobe Sound
Country: U.S.A
Vessel Name: Kumatage
Vessel Model: Grnd Bnks 46 cl
Join Date: Aug 2020
Posts: 13
Quote:
Originally Posted by oscar View Post
The wiring showed significant corrosion. So, that creates resistance which in turn causes heat, as well a voltage drop and then the amps go up to meet the wattage demand and keep the two A/C's (in his case) running.
Pitting on the connector blades also causes significant resistance. Pitting is caused by unplugging the cord without shutting of the breaker in the pedestal FIRST! The spark that jumps from the live outlet to the cord, on the dock and onboard, takes a small bit of metal each time it is unplugged. This makes the contact area pitted (less contact more resistance) thus heat.
Steve1.0 is offline   Reply With Quote
Old 10-13-2020, 09:02 AM   #10
Guru
 
City: Anacortes
Country: USA
Join Date: Nov 2012
Posts: 952
Quote:
Originally Posted by Bacchus View Post
Oscar
Its been awhile since I checked the stats but its interesting that more electrical boat fires are due to DC than AC. It goes against what many, myseld included, would think. I dont know but might guess there are more folks messing with DC systems that don't really know marine electrical and ABYC guidelines. Likely they figure its only 12V what can go wrong?
Here's a recent Boat US summary... DC about 3X the # of AC
https://www.boatus.com/seaworthy/mag...boat-fires.asp
No argument that boat inlet it worthy of frequent checks and good practices. And if a cord end looks suspect change the boat inlet at the same time. Both go bad and one bad end can damage a new mating one.


Itís been awhile since Iíve looked at the boatus data, but it suffered from being a summary. It did not allow interrogation of the denominator for those stats. Think of it this way, there are a,greater numbers of small boats than trawler style boats and even boats with shore power only a small percentage use it in the way the typical trawler does. So their statistic while true, is not as applicable to the typical marina with a bunch of floating boats around 30 to 60 feet in size. Iíd like to see the numbers with an appropriate classification.
ghost is offline   Reply With Quote
Old 10-13-2020, 09:09 AM   #11
Guru
 
oscar's Avatar
 
City: Bethlehem, PA
Country: United States
Vessel Name: Lady Kay V
Vessel Model: 1978 Hatteras 53MY
Join Date: Oct 2015
Posts: 832
Quote:
Originally Posted by rslifkin View Post
Don't forget to account for the multitude of boats that are trailered and either have no A/C power or never get plugged in.
Fair enough. But this point, and the others like it, are academic and not germane to the thread, ie the usual argument for argument's sake.

The point of this thread was for those that DO have shore power, which includes MOST of the people on this forum based on the avatars I see, to keep a very close eye on them as they are frequently the cause of fire on vessels so equipped.
__________________
Experience is a cruel teacher.... first it gives the test. Then it gives the lesson.
oscar is offline   Reply With Quote
Old 10-13-2020, 10:08 AM   #12
Senior Member
 
tozz's Avatar
 
City: Seattle
Country: USA
Vessel Name: Conundrum
Vessel Model: Nordlund 63' Pilothouse
Join Date: Feb 2017
Posts: 216
Quote:
Originally Posted by oscar View Post
[snip]
Don't know the stats of AC vs DC calamities, but I disagree with the statement that "Boats with AC systems are far and few between." Every boat in my marina has a yellow umbilical to the shore power pedestal and other marinas are similar.
This is a weather v. climate statement. AC shore power dominant for the boats observed in a marina but at least here in Washington, boats in a marina are the vast minority overall. We have an estimated 243,000 registered recreational boats (updated 2020 number) and over 90% of them are trailerable and 26 ft or less.

"The most representative boat in the Washington fleet is an 18′ fiberglass or plastic-hulled runabout powered by one or more gasoline outboard motors."

Some interesting stats collected over at the UW sea grant site:

https://wsg.washington.edu/community...te-boat-fleet/


-tozz
tozz is offline   Reply With Quote
Old 10-13-2020, 11:53 AM   #13
Senior Member
 
Redhook98's Avatar
 
City: Colonial Beach, VA
Country: US
Vessel Name: Tatoosh
Vessel Model: 1979 49ft MT RPH - restored
Join Date: Jun 2019
Posts: 166
I went to Smart Plugs after this almost burned up my boat. Upgraded interior main wiring as well. I am usually fastidious when it comes to my connections. My Portuguese Bridge door hit my cables and shook one loose. That won't happen again.
Attached Thumbnails
Click image for larger version

Name:	20200224_150835.jpg
Views:	34
Size:	74.1 KB
ID:	108887   Click image for larger version

Name:	20200224_150806_resized.jpg
Views:	35
Size:	63.2 KB
ID:	108888   Click image for larger version

Name:	20200223_141054_resized.jpg
Views:	32
Size:	107.3 KB
ID:	108889  
__________________
"Everything on your boat is broken.... You just don't know it yet."
Redhook98 is offline   Reply With Quote
Old 10-13-2020, 03:36 PM   #14
Guru
 
firehoser75's Avatar
 
City: Nanaimo
Country: Canada
Vessel Name: Pilitak
Vessel Model: Nordic Tug 37
Join Date: Feb 2018
Posts: 1,224
Redhook, you were lucky in dodging one there!! I am happy that you did.
Good advice on turning off the breakers before unplugging (disconnecting), and ensure that they are off when first plugging in as well. Connect or disconnect in the correct order as well, but not as important if all power is off.

I am surprised at how often I see people walking along the dock with a live cord end in their hands! Not only dangerous, but could, overtime lead to an overheat as discussed.
__________________
Tom
Nanaimo, BC
firehoser75 is offline   Reply With Quote
Old 10-13-2020, 03:48 PM   #15
Guru
 
oscar's Avatar
 
City: Bethlehem, PA
Country: United States
Vessel Name: Lady Kay V
Vessel Model: 1978 Hatteras 53MY
Join Date: Oct 2015
Posts: 832
Quote:
Originally Posted by firehoser75 View Post
Good advice on turning off the breakers before unplugging (disconnecting), and ensure that they are off when first plugging in as well.
Unless, like in my case, you have separate selector switches. No need to also turn off the breaker. Nothing is connected until you move the selector from GEN to SHORE or vice versa. Every boat is different.
Attached Thumbnails
Click image for larger version

Name:	AC Source Panel.jpg
Views:	31
Size:	102.1 KB
ID:	108893  
__________________
Experience is a cruel teacher.... first it gives the test. Then it gives the lesson.
oscar is offline   Reply With Quote
Old 10-13-2020, 03:51 PM   #16
Guru
 
firehoser75's Avatar
 
City: Nanaimo
Country: Canada
Vessel Name: Pilitak
Vessel Model: Nordic Tug 37
Join Date: Feb 2018
Posts: 1,224
Sure enough Oscar, but the general principle still applies.
__________________
Tom
Nanaimo, BC
firehoser75 is offline   Reply With Quote
Old 10-13-2020, 03:54 PM   #17
Guru
 
psneeld's Avatar
 
City: AICW
Country: USA
Vessel Name: Freedom
Vessel Model: Albin 40
Join Date: Oct 2011
Posts: 22,152
Ever notice how many melted plugs are reported/seen/encountered....but how few boat fires from that situation ever occur?
psneeld is online now   Reply With Quote
Old 10-13-2020, 04:06 PM   #18
Guru
 
oscar's Avatar
 
City: Bethlehem, PA
Country: United States
Vessel Name: Lady Kay V
Vessel Model: 1978 Hatteras 53MY
Join Date: Oct 2015
Posts: 832
Quote:
Originally Posted by psneeld View Post
Ever notice how many melted plugs are reported/seen/encountered....but how few boat fires from that situation ever occur?
And you have data for this?

https://www.boatus.com/magazine/2018...s-on-boats.asp
__________________
Experience is a cruel teacher.... first it gives the test. Then it gives the lesson.
oscar is offline   Reply With Quote
Old 10-13-2020, 04:08 PM   #19
Guru
 
firehoser75's Avatar
 
City: Nanaimo
Country: Canada
Vessel Name: Pilitak
Vessel Model: Nordic Tug 37
Join Date: Feb 2018
Posts: 1,224
Probably very true PS, but not a chance I feel should be taken. The boat next to me at an overnight dock had a small fire caused by this. Lucky, they woke up and dealt with it! They heard the popping and crackling near their berth/bed.
__________________
Tom
Nanaimo, BC
firehoser75 is offline   Reply With Quote
Old 10-13-2020, 04:31 PM   #20
Guru
 
psneeld's Avatar
 
City: AICW
Country: USA
Vessel Name: Freedom
Vessel Model: Albin 40
Join Date: Oct 2011
Posts: 22,152
Quote:
Originally Posted by oscar View Post
Just like your comment on most boats use AC...laughable.

No, I dont have stats and neither do you on melted plug ends, just real life experience and common sense. Like most dangers in life, the ultimate outcome is rare...thus the term "close call".

True, no one wants melted plugs or worse fire....but TF has to be one of the most fearmongering sources of info I frequent...granted I don't frequent many as my life revolves around boating both personally and professionally. So I keep to my lane most of the time.....comment on things close to my experience.
__________________

psneeld is online now   Reply With Quote
Reply

Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





All times are GMT -5. The time now is 04:03 PM.


Powered by vBulletin® Version 3.8.8 Beta 4
Copyright ©2000 - 2020, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2006 - 2012
×