Wiring a 50 amp 4 conductor 220V single phase plug with tray cable

Gentlemen,

I would appreciate some help with a wiring project. I have a new 200 amp single phase rural service for which I'm wiring service to an RV. The project involves wiring a 50 amp 4 wire 220 amp plug into the 200 amp main panel mounted to my meter pole. The plug will be housed in a rain proof box. The box will be mounted to the pole just below the 200 amp main panel.

I bought some AWG NO. FOUR tray cable. It contains 3 insulated conductors with bare ground (4 conductors). I have never used tray cable before. Upon peeling back the outer insulation I discovered to my surprise that the individual conductors are not color coded. Rather, they are all black and are labeled ONE, TWO, and THREE in white letters along the length of the individual insulated conductors.

My question is: Is there some accepted NEC "standard" designation for the two hots and the white? Or do I just arbitrarily assign ONE as red, TWO as black, and THREE as white (or whatever?) Call me a chicken but I find it unnerving that the conductors are not color coded.

Thanks!

Vernon

Reply to
Vernon
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Do your own color coding with colored tape. That is what the "professionals" do anyway. :-) ...lew...

Reply to
Lewis Hartswick

Sounds like three phase cable. L1, L2, L3 & neutral. Use 'Phase tape' to color code the wires.

Reply to
Michael A. Terrell

Michael,

Indeed it is. I was able to determine that on google. I have decided to go in alphabetical order: black red white. Therefore, black =3D 1; red =3D 2; white =3D 3.

Thanks to all.

Vernon

Reply to
Vernon

Vernon

One reply is correct about the cable you have being primarily for 3 phase. Another reply is correct in that you will be required by the NEC to color code the exposed wires. Exposed from the cable covering. I would use the bare conductor as the ground and label it green. Number one would be white as in the neutral wire. And 2 and 3 black and red.

I have some problem with your choice of mounting the "plug" in the box. I think you mean receptacle in this case and the cord from the RV, with a plug, will be connected to the receptacle. If the receptacle and/or service panel are outside they both need to be raintight. And the tray cable needs to be weather proof cable. Which it might or might not be.

Be sure that the RV is wired for two hots and the hots are 110 to ground AND 220 from each other. SINGLE PHASE. OR each hot 110 to ground and also the same hot in the panel. 2 each 110 volt 50 amp branch circuits in a single cable. May or not be NEC correct. Check with your AHJ if there is one.

Bob AZ

Reply to
Bob AZ

Michael,

Indeed it is. I was able to determine that on google. I have decided to go in alphabetical order: black red white. Therefore, black = 1; red = 2; white = 3.

Thanks to all.

Vernon

Reply to
Steve Lusardi

I am not an Electrician. I do, however own an RV. All of the RV outlets I have seen are 110Volt.

Reply to
Peter Divergilio

Then you have only seen 30 amp (NEMA 30-TT) and 15 amp (house standard)

The 50 Amp service for RVs is, indeed a 220 service (NEMA 14-50)

See

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Many RV dealers sell a "converter" plug system that converts an RV drop, that only has 30 amp and 15 amp outlets. They -hope- that the drop is wired with the 30amp on one leg and the 15amp on the other.

I do not recommend buying them

Reply to
Ralph E Lindberg

Ralph E Lindberg submitted this idea :

This thread is titled 220 volts and talks about 110 volts. I thought the standard for some time has been 120/240 volts on the archeic Edison system you use there.

Reply to
John G

[ ... ]

Hmm ... I would be skewed by the resistor color codes:

0 Black 1 Brown 2 Red (you hit that one, at least) 3 Orange 4 Yellow 5 Green 6 Blue 7 Violet 8 Gray (sometimes called Slate to avoid having two starting with 'G') Of course, you still have three starting with 'B'. :-) 9 White

Your colors are in numerical order using that system anyway. :-)

Enjoy, DoN.

Reply to
DoN. Nichols

The adaptor you buy for conversion from a 50 amp outlet does not convert 220 to 110 It simply changes the plug styles so you can plug in your 30 amp cord. As previously stated, I am not an electrician - I have, however, used an adapter to plug my 30 amp service cord into a 50 amp outlet at an RV Park. It worked fine for me. Your mileage may vary. (Apologies for stealing that tag line)

Reply to
Peter Divergilio

John, Both WYE and DELTA systems are used everywhere. However the WYE system is what is delivered to residences in the US. The difference between Europe and the US is that the secondary winding of the delivery transformer is center tapped for neutral The voltage between the center tap and either end of the secondary winding is 120 Volts. The voltage of the transformer end to end is

240 volts. Both systems are viable. Neither one is older than the other.

To put this thread into context, Vernon, by bringing in 4 wires, is connecting to the top of the secondary, the bottom of the secondary, the center tap of the secondary and safety earth. This provides 2 120 volt circuits as well as provide 240 volts if required, because the phase angle between the top and bottom of the secondary transformer winding is 180 degrees. Steve

Edison system you use there.

Reply to
Steve Lusardi

Shame on you DoN, SHAME! You can't expect the non-eletronics types to learn our secret technician's code!

You also left out Silver & Gold. ;-)

Reply to
Michael A. Terrell

Steve, I believe you are wrong. The system delivered to most USA homes is Single Phase with Centre tap grounded, hence 240 and 110 Any WYE system has 3 phases generaly seperated by 120 degrees giving voltges like 230 phase to centre point and 400 phase to phase. In most counties the centre point or Neutral is grounded. I believe also there are various DELTA sytems in the USA some with a leg grouned. VERY CONFUSING.

Reply to
John G

Archeic? From a nation with

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Wes

Reply to
Wes

Peter, did you bother to read the URL I posted? That clearly showed that the 50 amp service is a 220 service?

You can't get the kind of "conversion" you posted about unless the 15amp service is on one leg of the 220V and the 30amp is on the other (unless you are thinking of a simple plug converter, that just allows you to plug a 50amp plug into a single 30amp outlet)

Like so

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While I am talking about
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Where it states "...on separate circuits .."

Reply to
Ralph E Lindberg

[ ... ]

If 240 V, then 120 V, not 110. It rally varies from time to time. At the moment, I've got about 118.5 VAC -- sometimes it is as low as 115 VAC, sometimes a full 120 VAC.

While the power distribution is three phase Wye (usually at a much higher voltage), at residential distribution points, there is a single high voltage running down the street (one phase) relative to either the center point of the Wye, or to another phase (in which case it is two high voltage wires) going through a single transformer, and that transformer's secondary is 240 VAC center tapped, with the center tap grounded. This gives the 120 VAC either side of ground.

And nomenclature (and the nominal voltage change over time. It once was a nominal 110 VAC, then increased to 115 VAC, then 117 VAC, and currently 120 VAC -- each increase in voltage allowed a bit more power from a fixed gauge of wire.

Enjoy, DoN.

Reply to
DoN. Nichols

[ ... ]

I can't tolerate those. :-)

Enjoy, DoN.

Reply to
DoN. Nichols

Yeh Don," I must have been asleep when I said "hence 240 and 110" Of course it is 240 and 120. The rest is just as I understand it having spent about a total of 3 years in the last 46 years in USA and some of its remote outposts and worked for one of the largest US companies for 26 years.

The normal in Australia is 3 phase DELTA high voltage and 3 phase WYE at the houshold level 230/400 nominal with the centre of the WYE grounded. Not all housholds get (or need) 3 phases but it is generally in the cities and towns available at every pole.

Reply to
John G

That's why they were replaced by a number on SMD ;-)

BTW, I wrote a couple Javascripts for assemblers who are too lazy to learn the codes for SMD resistors & capacitors.

Here is the one for SMD capacitors:

Apparently Earthlink has deleted both the three & four digit resistor scripts, again. :(

Reply to
Michael A. Terrell

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