Burn cord

[KEVMAR]

What could have caused this burn ? What should I look for or how to prevent this from happening again . Thank you

 

[O C Diver]

Electricity.

Probably corrosion on the terminal making poor contact. If that was the boat end, replace the receptacle also. While the cord is rated for 30 amps, running close to the limit constantly increases the risk of this due to the contact size. Always make sure to turn the plug all the way for optimal contact before tightening the locking ring.

Ted

 

[Maerin]

What could have caused this burn ? What should I look for or how to prevent this from happening again . Thank you

A poor connection caused the burn. Arcing of the contacts due to age & misalignment of mating contacts. It's a poor design that is unfortunately in common use in 30A marine cords. A permanent solution is a "smart plug" that requires both plug & receptacle change. Or, change the plug to a new one of the same type. The mating connection is likely also damaged, it should also be critically inspected perhaps replaced. Keep cord ends out of the water, check for arcing/smell, spray contacts with T-9 or other to keep contacts corrosion free.

 

[boathealer]

What could have caused this burn ? What should I look for or how to prevent this from happening again . Thank you

1. Corroded contacts = resistance.
2. High current + resistance = heat.
3. Heat + time = FIRE!!!

Replace the cord (and the receptacle if the contacts are suspect).
Use dielectric grease on all contacts 2-3 times per year ($1.69 at Wal-mart auto section).

 

[High Wire]

Do you have two 30A shore power inlets?
If so, was this the cord that powers the air con?

 

[FF]

The most common cause seems to be dropping the plug into the water.

The wires inside the cover never dry properly and the resistance goes up.

Overloading will also cause a burnout as many CB have a time tolerance for over their rated current .

Purchasing a wire end that can be disassembled , and cleaned should help.

I prefer Hubbel , which seems to last longer than the cheapos.

https://www.fisheriessupply.com/hubbell-30-amp-125-volt-twist-lock-plug-hbl26cm11

 

[Ex Sailor]

What could have caused this burn ? What should I look for or how to prevent this from happening again . Thank you

May have been flawed (?) to start with, but I agree that it should be turned ALL THE WAY to lock it in place before the collar is turned. Looking at the photo, I think it's unlikely that the boat end is the problem ...... fb

 

[Xsbank]

What do you have plugged in? With 30 amps you are allowed 3600 watts (if you have 120 volts available). A cabin heater? Battery charger? Hot water tank? Lighting? Fans? Did you use a microwave? Toaster?

You need to total your load. The best way to discover if you are overloading is to use a meter and measure the power in the boat - if it is LESS than the unloaded power on the dock, ie if you are getting 100 volts on the boat, there is a serious risk of an electrical fire and at best, damage like you have just shown us.

 

[siestakey]

1. Corroded contacts = resistance.
2. High current + resistance = heat.
3. Heat + time = FIRE!!!

Replace the cord (and the receptacle if the contacts are suspect).
Use dielectric grease on all contacts 2-3 times per year ($1.69 at Wal-mart auto section).

BoatHealer is right this happened to me and many others on our dock in years past now any time I remove my cord I use Dieelctric grease from advanced auto ( but looks like the walmart one is cheaper) the brand I use is Permatex. Also when you put it on put on both contacts with breaker off and put the cord on and off several times. First your going to need to replace the end of that cord I would also have the marina replace the receptacle.

 

[Larry M]

... spray contacts with T-9 or other to keep contacts corrosion free.

We use a contact cleaner made by CRC. When we’re tied to the dock, once a month we spray both ends of the power cords and the female connecter at the pedestal. I've used it on boat electronics and hand held devices that I thought might be dead and it turns out it’s just a poor or dirty electrical contact.

 

[diver dave]

A poor connection caused the burn. Arcing of the contacts due to age & misalignment of mating contacts. It's a poor design that is unfortunately in common use in 30A marine cords. A permanent solution is a "smart plug" that requires both plug & receptacle change. Or, change the plug to a new one of the same type. The mating connection is likely also damaged, it should also be critically inspected perhaps replaced. Keep cord ends out of the water, check for arcing/smell, spray contacts with T-9 or other to keep contacts corrosion free.

I agree with this. The NEMA L series is a horrible design for durability in wet environments with either motion or frequent attach cycles. OK for inside factories, where they see good service.

 

[siestakey]

We use a contact cleaner made by CRC. When we’re tied to the dock, once a month we spray both ends of the power cords and the female connecter at the pedestal. I've used it on boat electronics and hand held devices that I thought might be dead and it turns out it’s just a poor or dirty electrical contact.

Great stuff I keep one of these at home and on the boat ( keep it in ziplock bag) using this in addition to the grease is a great plan

 

[bayview]

All of the above but the usual start of the process is is dropping in the water.

 

[FlyWright]

CorrosionX is another good product for the purpose. I use it on my connections after having a similar problem.

I also had to replace my boat receptacle since it was marred also. Now everytime I arrive at my boat in the slip, I touch the cord (both ends) to check for heat. No problems since I started using CorrosionX.

 

[Comodave]

+1 on the Smart plug. It has much more contact area to carry the current. I replaced both of my 30 amp inlets with the Smart plug.

 

[Baker]

The most important thing here is that you replace it. I call that "boat herpes". Because guess what???? That will cause heat on whatever it is plugged into. And it will spread that burn to whatever it is plugged into. And from then on it will keep spreading. If you have 2 30 amp cords and you keep interchanging them...it will spread to all cords and all onboard receptacles. Get it changed...NOW!!!

 

[Bacchus]

Agree w other answers and would add you should always connect / disconnect w no load by turning off breakers. If done under load the arcing will start the same process as corrosion.
This is a very common occurance w 30A cords.
These only make point contact and don't have a contact area like most recepticle / plugs do.
Do replace the inlet and cord plugs.

Smart plug design is much better IMO.
For a good summary take a look at

https://marinehowto.com/shore-power-cords-smartplug-vs-1938/
CM is a great resource for us boaters.

 

[High Wire]

Normally the burned contact is the physically smallest contact (the white/neutral/silver) but in this case it is the hot contact.
Loose wire connection on the black/hot/brass colored connector on either the plug end or the socket end. Replace BOTH since both will be permanently damaged.

 

[KEVMAR]

thank you all for the suggestions I am replacing the cord and receptacle.

 

[KEVMAR]

any suggestions on how to fix the power cord?

 

[siestakey]

any suggestions on how to fix the power cord?

Yes as FF said above put a new end on the link he gave you is for the other end but they and others supply both ends the Hubble brand he mentioned is good .

Also as someone mentioned above the smartcord has more contact surface but to fix just put a new end on

 

[The Other Gary]

Just buy a new end and waterproof boot at any marine store. cut back your cord about a foot in case the insulation heated back a bit. Same for the inlet if you have the available slack.
If you have Marinco inlets you can buy the replacement inserts. Don't let the Marine store sell you the Stainless steel mount and cover or you will own two.
They sell these for the 30 amp but not for the 50/125/25. If you ever have to replace the insert on a 50 just order the cheaper plastic covered unit and throw away the mount as the inserts are the same.

 

[The Other Gary]

Assuming that the power tower end of the cord is good then this is the opportunity to convert the cord and the inlet to smartcord.

 

[Bacchus]

You might look into the Smart Plug and compare costs w replacing both plug and recepticle.
I do belive they sell a retrofit kit w plug & recepticle.
Not sure what the premium would be but guessing not huge.

 

[tadhana]

A burn at the boa end means the cor end has over heated and the hull inlet is now damaged. Both must be replaced. I recommend a smart plug.

Dropbox - File Deleted - Simplify your life

 

[foggysail]

All of the above but the usual start of the process is is dropping in the water.

They will burn without ever being immersed. Very common problem with power cords.

BUT!!! Replacement cable connector are available and not hard to install. I replaced mine a few years ago. I also moved to a 50 amp power post and used Y splitter along with an additional power cord. Made life a lot easier.

 

[koliver]

We used to have a display board at our marina, loaded with burned ends. People gradually got the message:
1 Never connect without being sure the power breaker is in the OFF position.
2 If you see a burned end, replace it right away.
3 Move up to a smart plug, then this will not happen.
4 Many insurance Co.s will give a rebate towards the cost of the Smart Plug conversion.

 

[ghost]

I used to have cord issues like this, even after replacing components. I tried to keep up with maintenance and procedure such as securing the ring for awhile, then went a better way. Dropping in water is bad, but not required, they don’t last. Here is my overall approach. Renew the connection. If you go to smartplug, recommend getting the full molded cord, not just replacing the end. Next I stopped running more than 15 amps through my cable when I am not present. To do this required updating my inverter charger to a unit where I could set my shore power limit, in my case Victron, but there are other good choices. With a low limit on the cord current, it meant no longer running electric heaters while away. Replacement was a dehumidifier to keep the air fresh without heat circulation.

This is not the only possible approach, better part of the message is that you should think about the overall system as a whole. Burning shore power connections are a common source of boat fires in PNW as many don’t winterize, but try to keep boats semi warm with electric heaters. Cords just wont reliably do it unless everything is perfect and it rarely is so plan accordingly.

 

[Firestorm]

Consider installing a SmartPlug. They are a much superior product with more surface contact.