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Deep6 · 05-02-2014, 20:46

I was just given a 50 amp service cord by a guy that no longer had need of it. One of the ends are badly damaged and will need replacing but that is relatively affordable. However I am not certain what type it is. I recognise there are 2 type of 50 amp service. I believe my pedestal has a 125/250v service which I believe to be a 4 wire service. The cord appears to be a 3 wire cord which I believe is the 125v service. Is there any hope of using this, is there a converter or did I essentially just inherent someone else's disposal job?
Thanks everyone,

transmitterdan · 05-02-2014, 21:11

Both the 250V and 125V plugs have 3 prongs/sockets. The difference is that the 250V plug has 2 L shaped prongs and the 125V has a single L shaped prong. See the various types of connectors here: http://content.westmarine.com/wm-img...re-Power-1.jpg

mitiempo · 05-02-2014, 21:31

50 amp 125/250 volt cords have 4 wires. There are 3 prongs on the male end as well as a metal portion of the side for the fourth wire. If one end needs replacing just cut it off and count the wires. If it is 125 volt it will only have 3 wires. The female end is shown below with the side connector.

Deep6 · 05-02-2014, 21:38

Thanks for the replies guys, I suspected as much. Now the only thing (and I'll admit it's an ignorance based question) is, are there converters and such to adapt either or? I have now confirmed that the dock side is a 50a 125/250v female. Is there any hope of using this cord?

Deep6 · 05-02-2014, 21:44

I can confirm now that the cord is 3 wire...Any hope?

Dsanduril · 05-02-2014, 21:57

Yes, you can use a 50A 125V boat end on a 50A 125/250 dock end (although I'm sure I'll get lots of dissent for saying so). The 50A 125/250 circuit is actually two 50A 125V circuits with the circuits out of phase with each other. Your marina may not like you for using it this way, but it is electrically possible. You could wire it yourself (which you may not want to do since you are asking these questions), or you could just buy the adapter (which negates your "free" cable acquisition).

Hubbell HBL61CM72 Shore Adapter 50A 125 To 50A 125-250 Dock - 61CM72 Hubbell - Star Marine Depot

smac999 · 06-02-2014, 02:07

what is the service of your boat?...

Deep6 · 06-02-2014, 06:39

Right now my boat is 30 amp but with the big expense of the cable potentially behind me. I can definitely justify the breaker, outlet and ends to upgrade to 50 amp.

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Dsanduril · 06-02-2014, 06:46

It was too late for my brain last night. If you want to wire yourself, buy a 50A 125/250 plug:

50A 125/250V Male Plug | Marinco

The green wire gets connected to the green screw (that should also be labeled "G")

The white wire gets connected to the silver screw (that should be labeled "W")

The black wire gets wired to either of the gold screws (should be labeled "X" and "Y"). Doesn't really matter which one.

Then you'll have a 50A 125V cord able to plug into a 50A 125/250 outlet. If for some reason the cable you got is European coded then green or green/yellow is the same as green above, blue = white, brown = black.

That all presumes your boat is laid out for a 50A 125V connection and that is was the plug on the cord that was damaged. If it was the receptacle end then you'll need to replace both, and if your boat was intended for 125/250 then...

[Edit] we crossed typing paths. Buy both a 125/250 male plug end, a 50A 125V female end (if that was damaged) and a 50A 125V boat end plug and wire as above. [/Edit]

Deep6 · 06-02-2014, 06:57

I'm likely to have to replace both ends of the plug, I was thinking of going with the smart connector on the boat end. Is there any issue in doing so? Lastly to say that the cord is grimey us a bit of an understatement is there anything recommended to clean the jacket off?

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Dsanduril · 06-02-2014, 07:04

No problem with the SmartPlug at the boat end. The 50A version is 125/250 but allows the connection of either a 3-wire or a 4-wire cord. You should just make sure that you wire "X" to "X" or "Y" to "Y" since you will only be using one hot leg. On the boat you'll use a single-pole breaker and you'll have to make sure you connect to whichever leg you have as "hot" in your cord.

Never cleaned a power cord, but evidently others do:

STAR BRITE Cleaner at West Marine

mitiempo · 06-02-2014, 07:21

Quote:

Originally Posted by Dsanduril

On the boat you'll use a single-pole breaker...

There has to be a double pole breaker on the boat, whether 30 or 50 amp service is installed. Both hot and neutral have to be switched.

Dsanduril · 06-02-2014, 08:00

Quote:

Originally Posted by mitiempo

There has to be a double pole breaker on the boat, whether 30 or 50 amp service is installed. Both hot and neutral have to be switched.

I guess that depends on location and/or opinion. Personally I think that's a good idea, but at least in the US it is not a requirement. The NEC doesn't require it nor does the ABYC:

Quote:

11.10.2.8.1 Each ungrounded current carrying conductor shall be protected by a circuit breaker or fuse.

If the boat has an isolation transformer then on the boat side the neutral will be ungrounded and thus require a breaker. If the boat is not equipped with an isolation transformer then the grounded neutral gets carried over from shore. A breaker in the neutral is not required, but a reverse polarity detector is required.

Having said all that, I am in favor of a breaker in the neutral, it provides some additional protection against other people's wiring mistakes.