My wife needs reassurance

[Hoodsail]

I have a solution to make YOU $$ and calm your wife's concerns....if you need 75ft power cord, boat is obviously toooooo long, so sell her, and buy a 30+ ft cat. Pocket the extra $$ and use your 50ft cord with length to spare...just saying...thinking outside the "box" here... in fact with the extra $ you could have, you might even buy a 75ft cord!

[LoudMusic]

Originally Posted by SV__Grace

In my 40 years owning keel boats and keeping them in marinas, I've never had a marina inspect a shore power cord!

That you know of. If the dockhands and dockmaster are walking the docks, they're looking at things you may not even realize. Just because they've never said anything to you doesn't mean they haven't made other boat owners change their equipment.

[MicHughV]

I can tell you from personal experience, that extending a 30 amp, 50' long shore power cable is an invitation to trouble.
The prongs of the plug will get extremely hot, to the point of melting the end fitting.
Its a fire and electrical hazard.

[GRIT]

Originally Posted by j.g.evans

An alternative to the heavy 100' of shore power cable is to use a 100' 12 gauge power cord with adapters. This should be adequate for everything except air conditioning. And, much easier to store. Make sure the cable is 12 gauge and not 14 or 16 gauge.
Your splice job should be fine so long as it is not submerged. Use it until a marina objects and then switch to the above.

I am an electrical engineer and certainly would not spend the money for a longer shore cable unless I had to.

I'm going to give you the benefit of the doubt, being an EE, that you didn't realize he's connecting to a 30 amp supply.

You need a 10ga wire to carry 30 amps 75 feet. 12 ga wire is only rated for 20 amps at 75 feet. (Both at 5% voltage drop, which is too much in my opinion).

To the OP, and anyone reading this post:

Always be sure the wire can carry any possible current supplied. If you're attached to a 30 amp supply, your wire MUST be able to carry that current. You NEVER want the wire to be the weakest link.

Wire should be sized to the supply, not the draw. In other words, the wire is sized to the breaker supplying the current TO the wire, not FROM the wire.

Cheers.
Paul.

[waterman46]

Originally Posted by Dsanduril

Location, location, location...

In New Zealand your entire shore power system requires an inspection and Electrical Warrant of Fitness every 4 years and your shore power cable must be inspected and tagged annually.

https://www.bayofislandsmarina.co.nz...itions-of-use/

Good Grief! I hope the marina takes care of that detail for you every year. Hassles.

[John De Bree]

Have you considered just buying 75ft of wire and putting plugs on it's a lot cheaper in most cases. And your wife will be s lot happier

[wrwakefield]

Hi David,

Since you wisely decided on a new, longer cord, see if a local chandlery that caters to commercial fishing boats can make one up for you for less. [If not, and that is of interest, I will be in this commercial fishing port a few more days and can have one made... Call Piston and Rudder for a quote. They custom make 30A, 50A, 100A, etc. AC shorepower cords for the local fleet.]

More ideas... We also used the 30A 120V AC [i.e., 10 AWG 3 conductor] shorepower cable in summer the few times we make port. It is much easier than wrestling with the 50A cable [6 AWG 4 conductor...] If your boat is set up like ours and wired to accept 50A, consider having the custom 30A cord made-up with the 50A connector on the boat end. This is what I did, and it eliminates the 30-50A adapter at the boat [and another point of resistance...]

Except for brief touch-and-go's [your current modus operandi as I understand it] we use the heavier 50A cord so we have a full 100A of 120V AC for use onboard [instead of doing the Green Acres shuffle to keep from tripping the 30A shore power breaker. But only when we will be at the dock for more than a day or two.


Best wishes resolving things to your satisfaction...

Cheers! Bill

[NorthCoastJoe]

I don't think I would extend the cord, just would not feel right to me with the marine environment. As an ex-firefighter, it just goes against my better judgment.

But something to note: My well pump at home is 220 volt with 4 wires crimped and heat shrunk about 2 feet from the well pump that is 120 feet underwater. That is the standard installation method and no problems after 20 years.

[billgewater]

Electricity. Dangerous? Sure thing. An unhappy wife? Now that is much worse. Be a hero and do what she wants. Survival 101.

[Jim Cate]

Originally Posted by MicHughV

I can tell you from personal experience, that extending a 30 amp, 50' long shore power cable is an invitation to trouble.
The prongs of the plug will get extremely hot, to the point of melting the end fitting.
Its a fire and electrical hazard.

Why would extending the cable cause the plug prongs to overheat? I don't see the mechanism driving that.

Jim

[captlloyd]

Originally Posted by Jim Cate

Why would extending the cable cause the plug prongs to overheat? I don't see the mechanism driving that.

Jim

Huh, I was wondering the same thing ?

[belizesailor]

Originally Posted by Cadence

I believe your good.

Yeah, but he doesnt have to live w you!

What his wife "believes" is what counts...even if its incorrect!


[emoji6]

[Cadence]

Originally Posted by belizesailor

Yeah, but he doesnt have to live w you!

What his wife "believes" is what counts...even if its incorrect!


[emoji6]

Good point.

[Nani Kai]

Originally Posted by SV__Grace

The connection between the extension and primary cord shorted in wet weather.

When I need to use an extension to our shore power cables, I wrap the connection between the two with stretch wrap; the kind that comes on a roll and is often used to secure materials to pallets. The wrap holds the connection firmly together and makes it completely impervious to rain or standing water. I wouldn't trust it to be waterproof if submerged in the harbor but on the deck or the dock it works great.

As for spending $200 for a new 75' cable I agree that the money is well spent. The butt connectors you used are notoriously unreliable unless you swaged them together with the proper tool. I suspect that the heat shrink tubing used to waterproof the connection makes the joint very stiff so that coiling the line for stowage would require bending the joint which a butt connector doesn't tolerate well. If you have any incident related to joint failure I suggest that the repair/liability costs will far exceed $200. It's also possible that your boat insurance would use the DIY repair as cause for refusing a claim should there be an incident.

[MicHughV]

my boat used to be parked "bow in" the slip....this necessitated the 25' extension to the 50'-30 amp power cord....as the plug receptacles are on the transom....it was not a good situation.....

my solution....back the boat in......now I can use the 25' length power cord....problem solved...