Shore power plugs

[neilsty]

I had a shore power cable with a male 50A/125v plug. To use it on 50A 125/250v dock box I use an adapter cable. I had some corrosion problems with the male plug on my shore power cable so I replaced it with a 50A 125/250v male plug so I wouldn't have to use my adapter.

The issue I have is that the shore power cable is 3 wire, and the new plug is 4 wire. With the wires connected to ground, neutral and 1 of the two hots, I am getting 120v and the polarity is correct. With this setup am I able to get 50A? Does the adapter combine the two hot terminals from a 50A 125/250V shore power source to give a higher amperage? If it doesn't combine the two phases what does the adapter achieve? As I am metered on usage, does pulling power from one phase mean that I am paying for more than I use? Is the meter is recording amps used and assumes I am pulling from both phases - taking the amps and multiplying by 220v to get kwh, instead of the 110v I am actually using?

[wingless]

The wiring diagram for these plugs is shown in this Hubbell Marine Products Catalog.

The 50A / 125V pinout is shown in the top right corner of pg 17 / pg 11.

The 50A / 125V/250V pinout is shown in the top right of pg 18 / pg 12.

The watt-hour meter shows the energy consumed, regardless of the voltage(s) being drawn.

[neilsty]

Thanks Wingless. I am still unsure what the adapter cable does with respect to the X and Y terminals on the 50A 125/250v cable - does it just take one of these and connect it to the live terminal on the 50A/125v socket?

[wingless]

It is always best to use standard wiring w/ standard receptacles / plugs.

The modification under-discussion would create a non-standard wiring. The change does not appear to create a safety problem. An adapter would be a better solution.

The wiring diagram for the two plugs are shown.

For both plugs, G is ground, the green wire and W is neutral, the white wire.

The other pin(s) are the line connections, X and Y are L1 and L2 on the NEMA L14-50, the opposite phases of the 125VAC line voltage, those would be black and red wires. The unmarked pin on the NEMA L6-50 is the single 125VAC line voltage, the black wire.

Yes, the adapter would take X or Y and feed that to the line input on the power cord.


NEMA L14-50 - 125V/250V / 50A



NEMA L6-50 - 125V / 50A

[Zil]

Your question. The plug is only connected to one side of the source. However if the source is fused/breaker at 50 amps 250 volt, then you could draw 50 amp at 125 volt before tripping. But is it wise?