shore power cord problems

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........You are being mislead about using dielectric grease.

Well, that's a matter of opinion. Using dielectric grease to protect plug and socket electrical connections is a recognized method of doing so and it is effective.
 
Greetings,
I use coppersheild on my battery connections and as Mr. t. says, only a thin coat and he's correct about gloves and clothing...
 
Battery connections and shore power plugs and sockets are two entirely different situations. What is appropriate for one is not necessarily appropriate for the other.
 
Wes k,recognized by whom?Please elaborate.While I totally agree with your other points to the original poster,I don't quite understand your insistence on this point.I have been a member here for ten years,obviousely much more of a lurker than a poster,by design.I joined this forum to learn from people that have much more experience in the marine field in certain aspects than I do.I only contribute when I feel I have something to give back to this wonderfull site that has taught me so much.Not quite sure what your direct experience in the electrical field is/was,but I just retired after 45 years in the industry,have a masters license in two states,and spent 15 years in the commercial marine industry.So I felt that maybe I am slightly qualified to help out this poster,are you?I would never try to correct a professional in his direct industry such as trying to tell psneeld how to tow a boat,or dhays in the optical field.If you have something that you can professionally bring to the table in this subject,than please do so,but you just seem to be trying to argue a point you have no expertise in.
 
WesK I do not understand how the copper paste will increase the chance of arcing. Please explain.

Another great use for this paste is to seal the threads of your engine zincs. Stops leaks and yet maintains good conductivity.

For those looking to buy it, I generally get it from Amazon. CP16 Thomas & Betts Kopr-Shield Compound, 16-Oz
 
Like I said, just go with Boeshield. :lol:

P.S., You can even lube the plug itself and the threads of the locking ring with it.
 
I use Ilsco De-ox. Made to inhibit corrosion of electrical connections. We use it on temporary power cords on construction sites to minimize this type of problem.

Cut the end off of the tube and squirt a bit in the cord connector slots.

If you replace your power inlet use it on the wire prior to inserting it into the screw terminal.

Make sure you screw terminals are tight, check all of your electrical connections annually.

Bob
 
How often do you apply this grease?

The first of every month I spray Boeshield at the main plug-in in my cockpit. The extension cord gets it whenever I take it out of the locker.

Cords like yours I've seen many times online before. It's odd... the folks come out of the woodwork saying "spray your inlet" so I did. It's been eight years and so far so good.

That said, I've spent at least three years on the hook without a power cord so mine isn't used as much as some. And my power draws are low.

Not necessarily. Yours might. Most do not. There must be a breaker within ten feet (measured along the length of the wire) of the inlet. If the main panel breaker is within ten feet of the inlet, no additional breaker is required.

You know it's great to have a small boat. I'm within that ten feet with ease.

The advice to spray had anecdotal evidence and that was good enough to get me to do it. I did take out the inlet a couple years back and check the screws. That I should probably do as a regularly scheduled even. I'll add it to my calendar for a twice a year look-see, spring and fall.
 
A big part of the problem is having stranded wire under a screw terminal.

The wire crushes and separates so is hard to keep tight.

If anyone has purchased a DC Euro device in the past 2 decades , you can see the solution.

Their wiring is soldered at the end for 1/4 or 1/3 inch , which makes it more under screw head reliable.

It takes a very good soldering system to do a #6 or #8 wire , just at the end.
 
soldering and tinning are two different beasts,tinning recommended,soldering not.
 
The euro wiring is frequently tinned , looks like they just dip the end of the wire 1/4 inch into a pot of melted solder.

This solidifys the end weather its tinned or just bare copper., making it crush resistant under a screw.
 
A big part of the problem is having stranded wire under a screw terminal.

The wire crushes and separates so is hard to keep tight.

In marine systems, ABYC prohibits the screw from bearing directly on the wire strands. Hence these hull inlet and plug connections with have a slider between the screw and the strands or a rotating tip so that the strands are held securely and not twisted as the screw is tightened. This seems to work well. It prevents the strands from breaking and it seems to hold the strands securely. (another good place to apply Kopr-Shield)
 
Tinped

What is tinning????

Solderability and Tinning. Does The Industry Really Know the Difference? - Techtime NewsTechtime News

Tinning in the electronic industry is the process of dipping the electronic component terminations into a bath of molten solder alloy, creating a fresh inter metallic layer between the solder and the base metal and providing a highly solderable surface finish.

Sounds like what FF was describing. Not sure of the engineering there. Hard surface or crush surface...which makes for a better long term connection? I cant say.

If I recall correctly, ABYC doesn't prohibit soldering, it just says it can't be the only means of securing wire together and it must be properly supported to prevent working and breaking.

Awhile back I posted a link to Exide batteries I think...and they were pretty adamant about soldering battery terminals to prevent heat buildup from poor connections. I guess if you are guaranteed good connections no big deal, but for some, it is the belt and suspenders approach.

Funny how ABYC says screw connections of wires are OK but only if they have a plate in them...yet so many manfacturer's of marine equipment don't provide those terminations.
 
If anyone has purchased a DC Euro device in the past 2 decades , you can see the solution.

Their wiring is soldered at the end for 1/4 or 1/3 inch , which makes it more under screw head reliable.


Solder as used in this application is not permitted by ABYC. Studies have shown that vibration will work harden the copper at the solder point and the copper wire will eventually fail.
 
A process of heating the wire from the end,and drawing a very thin layer of solder up.Flux is not used.Inhibits corrosion long term on wiring.Marine cable usually is already tinned,so none required.That is why it is so expensive,as compared to regular copper cable.
 
I'm surprised that no one has mentioned the need to tighten the inlet wiring on the boat's sockets at least once a year. From what I've seen, that is the main reason that these types of melting pin events happen.

When the material surrounding a pin melts as shown in the opening post, it happens because of resistance. Something is getting between the inlet power cord and the receptacle on the boat. That "something" is resisting the flow of electrons and that resisting causes heat.

A non-conductive spray will help the outside of the pins - I use Corrosion-X. But what about the inside? Few people look there but I'll bet anything that if the plug shown in post 1 were taken apart, it was melting on the inside and not the outside.

When a plug like a shore power receptacle is installed, it is tightened as normal. But it's a big set of wires and even if tinned, it settles over a few months and creates small spaces. Those spaces are fertile ground for corrosion (resistance) and end up never getting treated.

At least once per year you should turn off the pedestal power and unplug the boat and remove all other AC power. Then unscrew the 4 screws on the receptacle on the boat and pull it out. Tighten the 3 or 4 wires on the inside. If you've never done it, I can pretty much guarantee that you'll turn each screw way more than you expect. As a last step, spray something like Corrosion-X on the wires on the back. Put the receptacle back and you're good to go.

Seriously - if you haven't done that in the last year, do it today. Report back the amount of tightening the screws allowed to convince others to do the same 10 minute fix.
 
Funny how ABYC says screw connections of wires are OK but only if they have a plate in them...yet so many manfacturer's of marine equipment don't provide those terminations.

Which manufacturers are you thinking of here that do not provide these terminatons.
 
Please do not confuse the idea that tinning a wire increases conductivity,it is actually the reverse.Solder consists usually of tin,and lead,both having a higher resistance than copper.The purpose of tinning a wire is that both elements have a higher resistance to oxidation than copper(copper turns darks when oxidized).Over the long term,the benefits of tinning far outweigh a slight increase in resistance as compared to the increase of copper resistance over a period of time due to oxidation.
 
It is always an excellent idea to check your electrical connections on a regular basis.A common problem I have seen is people believe that tighter is better,but understanding that torqueing(spellcheck?)is the proper way.Copper is a soft metal,and overtightening can actually crush the wire,and create more problems than it solves.A little industry trick when working with stranded cable is to tighten the initial connection,then give a slight counterclockwise twist to the cable.You will be amazed to find that the connection you just thought was tightened ,has now been loosened enough to get another quarter turn.
 
Seriously - if you haven't done that in the last year, do it today. Report back the amount of tightening the screws allowed to convince others to do the same 10 minute fix.

Good point. These screws do need to be checked periodically. This discussion was also on the MTOA list serve about a month or so ago. I was reporting a 30 degree above ambient temperature rise at my hull inlet (the slip we were in only had a 30 amp outlet) . When I tightened the screws I got 0 turns on the green grounding conductor. I turned the hot conductor screw about 1/4 turn but the grounded (neutral) conductor took 1.25 turns. That lowered the delta by 5 degrees. I then replaced the hull inlet entirely with a new Marinco inlet and that lowered the delta by 11 degrees. Later in the summer I replaced the inlet with a smart plug and the delta was only 3.5 degrees above ambient. All temperature tests were taken after the inlet was loaded to 26-28 amp for 30 minutes. One of my inlets was replaced 5 years ago and the other is original =8 years. I'm not sure which inlet was replaced 5 years ago, so this inlet was either 5 or 8 years in full time use.
 
Also,the two main reasons why electrical connections will loosen is vibration,and different expansion rates of dissimilar metals.Stranded wire is much more resistant than solid wire to the effects of vibration(why abyc doesn't recommend solid on boats).To help mitigate the different expansion issues,that is the purpose of the compounds previousely discussed on this post.Also,that is why abyc recommends using crimp on connections,as the tools are designed to not overtorque the strands.
 
Funny how ABYC says screw connections of wires are OK but only if they have a plate in them...yet so many manfacturer's of marine equipment don't provide those terminations.

Which manufacturers are you thinking of here that do not provide these terminatons.

The last two items were my battery charger and a fuse holder for my inverter.


More and more of the pieces of bigger equipment may be conforming...but the little add on stuff that you buy in marine stores like my fuse holder seem to be guilty.


They make nice connections for the fuse, then the wire connections seem to be an afterthought.
 
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The backplate actually has grooves cut into them,sort of like a lockwasher,to help mitigate loosening from vibration.
 
The last two items were my battery charger and a fuse holder for my inverter.


More and more of the pieces of bigger equipment may be conforming...but the little add on stuff that you buy in marine stores like my fuse holder seem to be guilty.


The make nice connections for the fuse, then the wire connections seem to be an afterthought.

thank you for your reply. What brand of charger is it? I have seen an automobile/RV inverter charger where the bolts bear directly on the wires, but i don't think i have seen a marine one like that.

Also what type of fuse holder are you using? I'm only familiar with the little inline holders that you crimp into the conductor, or the big fuse holders designed for bolted connections.
 
Wes k,recognized by whom?Please elaborate.While I totally agree with your other points to the original poster,I don't quite understand your insistence on this point.I have been a member here for ten years,obviousely much more of a lurker than a poster,by design.I joined this forum to learn from people that have much more experience in the marine field in certain aspects than I do.I only contribute when I feel I have something to give back to this wonderfull site that has taught me so much.Not quite sure what your direct experience in the electrical field is/was,but I just retired after 45 years in the industry,have a masters license in two states,and spent 15 years in the commercial marine industry.So I felt that maybe I am slightly qualified to help out this poster,are you?I would never try to correct a professional in his direct industry such as trying to tell psneeld how to tow a boat,or dhays in the optical field.If you have something that you can professionally bring to the table in this subject,than please do so,but you just seem to be trying to argue a point you have no expertise in.

Electronic technician was my career.


Dielectric grease is "recognized" by Marinco, one of the largest manufacturers of shore power equipment.
 
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WesK I do not understand how the copper paste will increase the chance of arcing. Please explain.

Unlike with battery terminals, you will be plugging and unplugging the shore power plug. As you do this, you will pull the paste out of the socket and spread it on the insulating surface between the pins. You now have a conductive material spread over the insulating surface and an increase chance of arcing.

This may or may not happen but choose a product that's not the most appropriate for the task?

You can use enough dielectric grease to seal the connection and any excess posed no risk of problems. Not so with a conductive substance.

Copper paste would be fine for permanent connections such as battery cables and electrical connections to panels and switches on the boat.

Each product has its best use. Use each where appropriate.
 

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