RV 50 Amp Electrical Explained....

[lineman1234]

It was a first for me too, as was the GFCI circuit breaker at the bottom of the panel.

Im not an inside electrician, just outside, but wouldnt that panel be used to just make things in the rv industry more simple and parts easy to get like a home application.

 

[CedarCreekWoody]

Im not an inside electrician, just outside, but wouldnt that panel be used to just make things in the rv industry more simple and parts easy to get like a home application.

Yes, it would. I think it is a great change and long overdue. Much more logical for anyone familiar with residential wiring.
Note in the photo that 20 amp breaker that I added; just a residential Square D brand that I had on hand. The originals are Siemens brand.

 

[Scott'n'Wendy]

Yes, it would. I think it is a great change and long overdue. Much more logical for anyone familiar with residential wiring.
Note in the photo that 20 amp breaker that I added; just a residential Square D brand that I had on hand. The originals are Siemens brand.

As was pointed out to me by xrated...or whatever handle he goes by now..lol...all the breakers in current RV panels are common residential breakers. The arrangement of the bus behind them makes no difference.

 

[Jomani]

@lineman1234 - the video is all about proving a theory regarding the direction of current flow which can be a hard concept to grasp at first, especially when learning AC simply because it alternates. There would be no logical reason to wind one side of a transformer in the opposite direction except to help explain a theory.

The “out of phase” happens anytime you tap a transformer and use that as a reference point. Tapping the center of the windings simply ensures matching outputs.

If you could stop time and measure the direction of current flow in a specific instant, you would find that current flows out of the secondary windings of a transformer at L1 while at the same time flowing into the secondary windings of the transformer at L2 (simply completing the circuit with L2 being the return path). With that in mind, the 120 volt circuits would have the grounded center tap as the return path so, while L1 is pushing (current flowing out), the center tap is pulling (current flowing in). At that that same moment in time L2 is pulling (current flowing in) wile the center tap is pushing (current flowing out).

With each 120V circuit pulling/pushing on the neutral line at the same time, perfectly balanced loads would cancel each other out and leave no current flowing on the neutral wire. All that said, the current flowing on the neutral wire is “out of phase” since L1 and L2 have current flowing in opposite directions at the same time.

A simple way to test that theory in an RV is to put a clamp-on ammeter on the incoming neutral wire and run just one air conditioner. You should read whatever the normal amperage draw is for that air conditioner. Now turn on the second air conditioner. The current draw on the neutral wire should drop to almost zero because it is running off the other 120V circuit.

 

[lineman1234]

In a 120/240 volt transformer, there is no center of the winding. There are two 120 windings each giving 120 volts from one beginning to the end of the winding.
Then one winding from the last of said two that 240 windings giving 240 volts.
If its one thing i know, its how transformers the electric company uses, as i did linework for 32 years.
I am seeing no out of phase, just the difference in adding the other 120 windings to get said 240 volts, thats how it works.

All 3 windings of the transformer, primary one of the 120 and the other 120 winding are going up and down, alternating at the same rate and time, thats how it works. The neutral carries the unbalance that is constantly changing.

 

[lineman1234]

On/in the inside of the transformer, 120/240 there are 4 secondary ends, nothing is tapped off mid point of anything. A and B one winding on the secondary side 120 winds, then C and D the second winding of the other 120 wind.

This is how on of 3 transformers makes 3 phase 120/208 volts, by taking each transformer and putting A and C together then B and D together each transformer gives 120 phase to ground, then 208 phase to phase.

Not to be confused with how the common 120/240 volt transformer, with 3 of them make 3 phase 240 phase to phase, just wired differently to do so.
But to add, 2 transformers can be wired to give 3 phase 240.