Marinco 30 Amp Shore Power Inlets

[rwidman]

Originally Posted by zeehag

since 1990 i have not burned out any shore power cords or plugs.
but then i always remember to twist them locked to complete the ground circuit.
have used 20 and 30 amp no issue. used 50 amp no issue.

Apparently, they are a problem for some folks but not for others. A little dielectric grease goes a long way towards avoiding corrosion as does not dropping the cord ends in the water.

With the screw on ring, they are "rain tight" so water is not an issue.

If you twist the cord counter clockwise before you plug it in, it will have a natural desire to return and that tension helps to keep the plug in the socket.

Most folks do just fine with the standard twist lock plug and socket. Nobody at my marina has changed over to a different plug/socket and new boats rolling out of the factories still have the standard twist lock design.

[rwidman]

Originally Posted by john61ct

The people own the airwaves, regulated federally.

I believe electrical codes for marina are the responsibility of local jurisdictions?

There is the National Electrical Code (NEC) and most local jurisdictions incorporate this into their local codes, sometimes with modifications or additions.

The newest NEC requires ground fault protection for the circuits supplying power to the boats but only for new or renovated or rewired docks. Just like they don't make you rewire your home when the code is updated.

I don't believe the code specifies the type of connector, only that they meet certain requirements.

In any event, a marina that converted its receptacles to anything non standard would have lots of complaints from customers and potential customers who couldn't connect to the electrical supply. This would be a very bad business decision.

The thread here is about the boat end, not the shore end and a boat owner can use any sort of connector he or she wishes. It doesn't have to be a twist lock, it doesn't have to be a "Smart Plug", it can be anything with three connections that will carry the total current. As I attempted to point out earlier, there are disadvantages to not using what is standard on boats and used by 98% of boaters, but it's the boat owner's choice.

[Dockhead]

Originally Posted by john61ct

No, greater surface area, self-wiping like Andersons and waterproofing, or at least IP-rated splash protection, should all be required no matter what.

And it isn't high-current overloading causing the problems, but increased resistance from the above design failings, fires can start well below the CP limits.

MaineSail claims a great number of fires are caused by shore power connectors.


Someone asked about the European blue connectors. In fact they are not specifically European, but a worldwide standard connector, not used only in North America where we have a competing set of standards known as NEMA. The blue (and red) connectors are called IEC 60309, and they are also referred to as "CEE connectors". See: https://en.wikipedia.org/wiki/IEC_60309. They are color-coded according to voltage -- blue is 250v and red is 400v. They are all minimum IP44, so splash-proof from any angle, and you can get any of them also in IP67, which is really waterproof and safe for immersion for 30 minutes at 1 meter depth.

They are inexpensive but very well designed with robust brass pins and large contact area. I have never heard of anyone burning one up.

For a boat shore power connector, I think it is absolutely essential that they are fully splash resistant -- IP44 -- at the very least. Besides the terrible contact surfaces as described by MaineSail, the other big problem with the Marinco/Hubbel connectors is that water gets into them. I used to have to unplug and wait in heavy rain -- just when I most needed my electric heat. The water poured in not only around the socket interface itself, but also where the wire entered the plug body -- which totally lacked any kind of weatherproofing. I have no idea why I put up with that for so many years


Concerning the SmartPlug -- I note that some people were disappointed that the thermal breaker was removed. I don't think that would bother me, really. Such an obviously well-designed device, with very good water protection to boot, ought to be very reliable.

[john61ct]

So say I wanted to use the better CEE / IEC 60309 design on my end, ordered the outlets and plugs.

Could someone link to good plugs to fit "normal U.S. standard" 50A receptacles?

And an adapter to fit the same at 30A?

As well as top-quality wiring?

Goal being to make our own custom lengths.

If special crimpers needed, please spec them too?

Most appreciated. . .

[Dockhead]

Originally Posted by rwidman

. . . In any event, a marina that converted its receptacles to anything non standard would have lots of complaints from customers and potential customers who couldn't connect to the electrical supply. This would be a very bad business decision.. . .

Yes, obviously, it can't be done by one marina owner acting alone. There would have to be some kind of mass movement towards a better type of connector based on some kind of standard. There doesn't seem to be anything suitable among the NEMA standard types of connectors: https://en.wikipedia.org/wiki/NEMA_connector

So I guess we are stuck in North America, for the forseeable future, at least on the pedestal side.

[john61ct]

Also, any ideas about how many 12V amps these CEE / IEC 60309 connectors would be good for?

Yes I realize could be problems, just for science. . .

[Dockhead]

Originally Posted by john61ct

So say I wanted to use the better Euro design on my end, ordered the outlets and plugs.

Could someone link to good plugs to fit "normal U.S. standard" 50A receptacles?

And an adapter to fit the same at 30A?

As well as top-quality wiring?

Goal being to make our own custom lengths.

If special crimpers needed, please spec them too?

Most appreciated. . .

I would just use a Smart Plug in your case, I think. What's not to like about them? They aren't even that expensive.

Alternatively, the Ratio plugs: Plugs - Marine - Products - ratio

Just take your normal shore power cord and cut off the boat side connector. The conductors on both types are clamped with screws, so you don't need to crimp anything.

Even the standard cheap CEE blue plug (which only costs three or four bucks) has a lovely strain relief/waterproofing gland which grips down on the cable to make a waterproof seal. Dead simple to install on your existing cable.

[Dockhead]

Originally Posted by john61ct

Also, any ideas about how many 12V amps these CEE / IEC 60309 connectors would be good for?

Yes I realize could be problems, just for science. . .

I think the ampacity of cables and connectors are roughly the same between AC and DC at mains power frequencies (skin effect is negligible, unlike at RF frequencies). Someone more knowledgeable than I might correct this.

[john61ct]

Looks like the US 50-Amp connectors we're talking about here are non-NEMA "California standard", is that correct?

If so, looks like there are some very robust plugs&ports made for the construction industry, some even waterproof, that may be interoperable with the Marinco style in a pinch?

Not saying inherent design flaws aren't there, but maybe wouldn't need replacing as often?

[john61ct]

Originally Posted by Dockhead

I think the ampacity of cables and connectors are roughly the same between AC and DC at mains power frequencies (skin effect is negligible, unlike at RF frequencies). Someone more knowledgeable than I might correct this.

I did say 12V, so no.

In theory, 50A * 120V = 6kW , 6000w ÷ 13 = ~450A

but I don't know if other factors come into play

[john61ct]

Originally Posted by Dockhead

Just take your normal shore power cord. . .

I don't have one long enough I trust, and also I was thinking about making up a few, different lengths, different uses.

[john61ct]

Originally Posted by Dockhead

I would just use a Smart Plug in your case, I think. What's not to like about them? They aren't even that expensive.

Alternatively, the Ratio plugs: Plugs - Marine - Products - ratio

I was asking about wire and "the other end" to go into standard marina / RV pedestals.

[Rigdaddy]

Originally Posted by zeehag

since 1990 i have not burned out any shore power cords or plugs.
but then i always remember to twist them locked to complete the ground circuit.
have used 20 and 30 amp no issue. used 50 amp no issue.

No issues yet with my 30 amp or 50 amp Marinco plugs (knock on wood). They’re eleven years old. However, if the smart plugs are that great, I’ll check them out when mine finally give up.

[DeepFrz]

Originally Posted by Rigdaddy

No issues yet with my 30 amp or 50 amp Marinco plugs (knock on wood). They’re eleven years old. However, if the smart plugs are that great, I’ll check them out when mine finally give up.

When your Marinco plugs finally give up you may not need the Smart Plugs. Check the contacts regularly and carefully, use a bit of dialectic grease on them if they are still okay and check the plug using an infra red thermometer.

[rwidman]

What everyone should keep in mind is that a damaged or corroded end on the shore power cord will eventually damage the fixed end and vice versa.