Electricity? Never touch the stuff

[L8173]

I'm hiring an electrician to run a 50 amp line at my daughter's house for my RV. I only need 50amps because I have two A/C units. It's a 30' toy hauler. No W/D hookups. Everything is 110 (I believe). Having a difficult time telling the electrician exactly what I need, since I don't really know myself. My cord is a four post cord. What should he run?? He's saying 220, but I don't want to blow stuff up. ANY info on this basic question would be appreciated. I've just never been able to grasp the concept. Please use small words, lol.

[Range_Maggot_Bo]

RLS7201 wrote:

myredracer wrote:

road-runner wrote:

OMG... I wish people would stop referring to "phases" in reference to 120/240 volt circuits and services.

You might have a tough time with this. For examples, I used google to search for "120/240 volt circuits and services", and 4 of the first 5 hits talked about phase. My similar thing is that I wish people would stop bringing up calories when I go for the cookies or chips.

I spent a career as an EE in the construction biz and can tell you it's always been line 1 & line 2. Go look at a 120/240 volt panel, meter base or fused disconnect switch somewhere and see what the labeling says on it. A 120/240 volt circuit/service is commonly called "single phase" but each hot leg is never referred to as a phase.

Go by what internet "pros" say if you want tho...

As an EE you should know better. The true definition of 120/240 service is indeed "SPLIT PHASE". There is no other way to define it. If not for the split phase definition, there is no way to explain why the neutral lead can be the same size wire as L1 & L2 wires. Single phase is for rookies & EE that don't truly understand the mechanics of split phase.

Richard

Also an electrician here. Never heard it called "split phase". Never really heard the word "phase" unless working on a 3phase motor or 3phase system. Single phase or 3 phase system. That simple and that's what it's known as in the profession. Don't know where you got your electrical experience Richard.

[MEXICOWANDERER]

For non-industrial sitting on the power pole

H1 and H2 transformer line voltage input

L1, L2, L0, output to the service drop.

L0, of course, is neutral

SPLIT PHASE motors do not need start or run capacitors. Their startup draw can be 5 to 8 times that of run current. Just the thing to not connect to a new digital demand meter. Split phase motors are 120vac like vacuum cleaners.

Wanna have fun? Take your meter aboard a trawler and start searching for low voltage leaks. Or ground interfaces between dock power and generators. Exposes self-declared EE's in mere seconds. Zincs and propellers are not inexpensive. Another way to expose a fraudulent "EE" is to turn him loose on a bank of transformers trying to resolve an earth ground eddy loop.

Analyze a 50 amp 240 service

L1 to LO volts
L2 to LO volts
L1 to L2 confirmation
L pick one to earth ground
L0 to earth ground

Most campgrounds have 3-phase and 99% of the time you will discover by moving around and checking the weak sister phase lowest voltage of the three phases. The problem is when you suck down 2 of the 3 phases the third tends to rise.

Carlos had me wire up a Scott connection for the heaviest loaded spaces in his Mazatlan Park.

[RLS7201]

myredracer wrote:

road-runner wrote:

OMG... I wish people would stop referring to "phases" in reference to 120/240 volt circuits and services.

You might have a tough time with this. For examples, I used google to search for "120/240 volt circuits and services", and 4 of the first 5 hits talked about phase. My similar thing is that I wish people would stop bringing up calories when I go for the cookies or chips.

I spent a career as an EE in the construction biz and can tell you it's always been line 1 & line 2. Go look at a 120/240 volt panel, meter base or fused disconnect switch somewhere and see what the labeling says on it. A 120/240 volt circuit/service is commonly called "single phase" but each hot leg is never referred to as a phase.

Go by what internet "pros" say if you want tho...

As an EE you should know better. The true definition of 120/240 service is indeed "SPLIT PHASE". There is no other way to define it. If not for the split phase definition, there is no way to explain why the neutral lead can be the same size wire as L1 & L2 wires. Single phase is for rookies & EE that don't truly understand the mechanics of split phase.

Richard

[road-runner]

philh wrote:
ME here... L1 and L2 are not on the same sine wave phase... 2 phases 🙂

That statement should be good for another 5 pages on the thread! I'm worn out beating that horse, just going to watch this time.

[philh]

ME here... L1 and L2 are not on the same sine wave phase... 2 phases 🙂

[road-runner]

You're totally right about the L1 and L2 labeling, and I have to admit for wiring the various 120/240 components you just have to make the right interconnections and not really know what's flowing in the wires. Where did phases come into the thread? I think it started with two comments that "it" is actually two 120 volt circuits. A risky oversimplification, IMO. Then post 19 asked an innocent question about connections and phases, which falls cleanly under the two 120 volt circuits umbrella. That's when the bottom fell out with a mix of correct and incorrect explanations related to phases. Looking from the other end of the EE spectrum, the low-level circuit end, I have a hard time viewing the 120/240 volt service as anything but phase relationships.

[myredracer]

road-runner wrote:

OMG... I wish people would stop referring to "phases" in reference to 120/240 volt circuits and services.

You might have a tough time with this. For examples, I used google to search for "120/240 volt circuits and services", and 4 of the first 5 hits talked about phase. My similar thing is that I wish people would stop bringing up calories when I go for the cookies or chips.

I spent a career as an EE in the construction biz and can tell you it's always been line 1 & line 2. Go look at a 120/240 volt panel, meter base or fused disconnect switch somewhere and see what the labeling says on it. A 120/240 volt circuit/service is commonly called "single phase" but each hot leg is never referred to as a phase.

Go by what internet "pros" say if you want tho...

[Lynnmor]

DrewE wrote:

Lynnmor wrote:

When I see the word "phase" in this type of discussion, I quit reading right there because no good information is forthcoming.

I hope that's only if it's in connection with the number "two". Last time I checked, "single phase" and "split phase" are perfectly valid descriptions of typical north American household electric service, and they both have the word "phase" in them. :B

You may have missed "in this type of discussion". 😞

[DrewE]

Lynnmor wrote:

When I see the word "phase" in this type of discussion, I quit reading right there because no good information is forthcoming.

I hope that's only if it's in connection with the number "two". Last time I checked, "single phase" and "split phase" are perfectly valid descriptions of typical north American household electric service, and they both have the word "phase" in them. :B

[road-runner]

OMG... I wish people would stop referring to "phases" in reference to 120/240 volt circuits and services.

You might have a tough time with this. For examples, I used google to search for "120/240 volt circuits and services", and 4 of the first 5 hits talked about phase. My similar thing is that I wish people would stop bringing up calories when I go for the cookies or chips.

[Lynnmor]

myredracer wrote:
OMG... I wish people would stop referring to "phases" in reference to 120/240 volt circuits and services. In the elec. industry, the two hot legs are always referred to as simply line 1 and line 2.

When I see the word "phase" in this type of discussion, I quit reading right there because no good information is forthcoming.

[myredracer]

OMG... I wish people would stop referring to "phases" in reference to 120/240 volt circuits and services. In the elec. industry, the two hot legs are always referred to as simply line 1 and line 2. See diagram below.

To the OP, (if he comes back) I would not ignore voltage drop in the circuit if wanting the full 50 amps available (as opposed to just needing to run converter, fridge and other light loads). That would include overall length of all wiring from RV panel all the way back to the panel in the house. A calc. should also consider actual voltage at the house's panel. It is possible that heavier ga. wire is needed, but probably okay.

CA Traveler wrote:
3 phase for residential and CG's??? Yea right that will happen right after the US switches from 120V to 240V. The UK did that right with 220V and 50Hz.

RV parks are permitted to be connected to 3-phase 120/208 volt services if the secondary of the transformer is a "wye" configuration. The two hot legs are 120 degrees apart and referred to as phase A & B (or A & C or B & C) and the voltage from the neutral to a phase is 120 volts. See diagram below. Since it's uncommon for RVs to have 240 volt appliances, the reduced voltage of 208 doesn't affect anything. 120/208 volt services in CGs aren't very common but they are out there and you'd never know unless you used a voltmeter.

[MEXICOWANDERER]

I don't blame him.

Can I describe how to parallel a high voltage bank of transformers by testing for additive or subtractive polarity? My tip about 50 amp stove receptacle and connection should have steered him in the correction direction. The 1,2, N and green earth ground labeling inside the plug should be Dick & Jane to any legit electrician

[2oldman]

Op is gone.