Generator on 220

[PCrabill]

I just bought a Homelite(John Deere) generator. It is a model LX5600. 5600 surge watts and 5000 continious. The question I have is off of the 4 pin 220 conector, going into a 50 amp receptacle, will my trailer switch everything over to 110? I have camped using 50 amp services and I'm not sure if this is 220 or 110. I never gave it much thought until I got the generator. I don't want to have a expensive repair due to too much current. The trailer is a 96 Holiday Rambler 38ft' with 2 slideouts and 2 AC units. I am looking forward to using the generator in area's we dry camp at. By the way I paid $399. 99 for the generator at a BJ's store. I thought it was a great price.



Thanks in advance for your assistance.

 

[Texas Diesel]

your generator has two 110V windings in series for 220V, they are wired in parallel for full power 110V. I would suggest, if your generator has a full power 110V plug, (they are usually 3 prong round twist lock) to use a 50 to 30 Amp adapter and use the full power 110V connection on the generator, that way the load is spread between both stator windings on the generator. If you use the 220 V plug on the generator you run a risk of having an unbalanced load on the generator because it is using each 110v stator winding to supply power to 1/2 of your trailer and the loads in the trailer may not be equal between the two halves, plus the generator regulates the voltage based on one of the 110V stators anyway.

 

[bombero]

Boy if it was me I would not hook it up to my RV until I knew for sure that everything was OK. The price you paid was way to cheap for what you got! Maybe it way some military thing that is set up for overseas?? Just IMP

 

[FParisi]

The trailer WILL NOT convert the 220 to 110. The 50 amps in RV parks is 110. The reason it has 4 leads is 2 hot 110s = 220 +common + ground.

You can get some pretty cheap generators but they tend to be noisy!

Frank

 

[BK]

FParisi is correct as well as Texas Diesel.

But since no one as yelled it yet I will simply yell... ... ... ...



DO NOT PLUG YOUR TRAILER'S PLUG INTO THE 220VAC OUTLET ON THE GENERATOR. YOU WILL TOAST THE ELECTRICAL ITEMS IN YOUR TRAILER.



The camp sites are 110Vac.



Your trailer is designed to run off of 110Vac, NOT 220vac.



When a power source has a current rating such as "50amps", that is it's CAPABILITY. It will deliver up to 50amps.

So if you only need 20 or less, no problem.



220Vac is the potential, or "voltage"... the ac electrical loads in the trailer are only designed to run off of 110Vac.





The 220Vac outlets in SOME generators general only bring out the "high" side of either phase and the ground. Not the needed netuel. As Texas Diesel stated for many other reasons as well, don't bother with the 220Vac outlet unless you have a specific 220Vac load to run.

 

[drees1]

50 amp Camp grounds

I don't want to flame anyone, but lets double check whats happening at the 50 amp socket at the campground. I must admit that I only have a 30 amp system, so I never bothered to stick my voltmeter into the 50 amp socket. But, as I have a conversion bus and surfed their sites for years, the conclusion was that you get 2 hot leads at 220v to each other, a neutral, and a ground. You can pull a full 50 amp from each leg to neutral at 110v, which is the same as 50 amp across the 2 hot legs. The proof of this is in your wiring. If both hot legs were the same phase then the neutral would have to be twice the size to carry 100 amp. When the 2 hot legs are out of phase (220 volts) then the neutral carries NO current when both legs are fully loaded due to the oposing phases in the common neutral. The maximum the neutral will carry in a 220 setup is 50 amps when 1 leg is fully loaded and the other is no load. You can verify this by confirming that your neutral wire is no larger than either of the hot leads. Now with all of that said, many camp grounds have terrible wiring with all sorts of problems, and you may find one wired incorrectly.

If I'm wrong here let me know and explain why.



Doug Rees

 

[BK]

drees1 . .

"you get 2 hot leads at 220v to each other, a neutral, and a ground"



-you do get two hot leads. . phase A and phase B, usually a ground. . not always the neutral, here's why (and more on the magic of the netural wire)...



The only time the neutral is used is in certain three phase connection. It's been some time for me... so I honestly forget which one. . but the two three phase connections are Delta and Y.

One of them uses the netural in the wiring scheme... but the netural is not used in a two phase 220Vac connection.



So even to follow your logic, it's not that the total current that is the sum of all three phases... . but the time inwhich the current is carried, since each is 90 degrees out of phase from one another.

They don't canceal, to put it more simply, they are "time sharing" the wire!



Each phase is 90 degrees from one another, not 180 as you maybe thinking... . like a + or - to canceal each other. It doesnt happen that way. If it did, we wouldnt need super conductors... we'd have our solution at hand already! (no flaming,, just a funny thought that occured while I was typing this)



When you have 220 from only two phases, the power is drawn from across the two phase (which have a common node at neutral), but neutral is never connected to the load.

So the neutral has nothing todo with the load connection.

 

[Dave Zuber]

Originally posted by BK

drees1 . .



The only time the neutral is used is in certain three phase connection. It's been some time for me... so I honestly forget which one. . but the two three phase connections are Delta and Y.

One of them uses the netural in the wiring scheme... but the netural is not used in a two phase 220Vac connection.

EL-WRONG-O BK, a neutral is used is for all single phase 220v/110v in all common house wiring. The two legs that supply 220v are really just two 110v legs that are 180 deg ouf of phase when you reference to the neutral. For 110v you connect to one of the 220v legs and the neutral. The neutral carries current. I couldn't follow the rest of your discussion.



The Delta 3 phase you refer to adds a third 'wild' leg to the common single phase to emulate 3 phase and is common for Farmers and Machine shops. You can pull 110v single phase, 220v single phase and 220v 3 phase from the same source.



The Y 3 phase doesn't have a neutral, can be any of 200v/208v/230v/460v/575v and common in industrial wiring. You only get 3 phase.



Everything has a ground, it does not carry current, it is just for safety.



I would recomend that if the plug on the generator EXACTLY matches the plug on your camper, then they are compatable IF they are wired properly. All bets are off if you are using gender changers that are improperly made. How do you know the wiring at the campground is correct when you plug in?? There are standards. If you're concerned, you can buy a simple circuit tester at the hardware store for about $10. Turn off everything in the camper, plug it in, and check what voltage you have at the 110v outlets.



If you're still unsure about all this, quick stop at a camper service center with the generator could save a lot of problems.

 

[BK]

"EL-WRONG-O BK, a neutral is used is for all single phase 220v/110v in all common house wiring. The two legs that supply 220v are really just two 110v legs that are 180 deg ouf of phase when you reference to the neutral. For 110v you connect to one of the 220v legs and the neutral. The neutral carries current. I couldn't follow the rest of your discussion. "...



Dave, Not sure where you think I'm "EL Wrong-O"... but this is fact...

When one wires a 220Vac outlet for lets say an Airconditioner or an electric dryer in a house... one brings only phase A , phase B and ground. The current is drawn from across phase A and phase B. The neutral is NOT brought from the panel to the outlet. The Neutral is in the panel and the common node from which the two phases are referenced. Yes the currents do flow from the panel to the pole, to the transformer. But the load (dryer or ac) doesn't use the neutral in it's connection. I agree neutral carries current..... but the neutral is not connected to the load directly.



If you can pull 110 from a Delta and 220 from between any of the phases , than there is a neutral. It's the common node that the three phases are joined at and referenced to, and since each of the three phases are 110... it goes as such. .

phase A to neutral = 110

phase B to neutral= 110

phase C to neutral =110

between any of the three phases is 220.



I'd be happy to expand on what other areas I wasnt clear... but I was addressing Drees1's thinking the the current's cancealed and nulled themselves out in the neutral.

 

[drees1]

Some more clarification here. Delta 3 phase has no neutral. To get 120 out of 240 3 phase delta, the center of one winding in the transformer is tapped to neutral which is grounded at the utility pole and service entrance. 120 is then derived from either end of the the tapped leg giving the user 2 legs of 120 on the 3 phase delta source. The 3rd leg is called the wild leg and it's node is 360 volts to ground and cannot be used to get a 120 volt output. But all three legs are 240 to each other.



A "Y" connection, spelled Wye, has a center neutral node and 3 legs with 1 end each joined to the neutral. Any leg of the wye to neutral will produce 110, and any leg to leg will produce 220.



Normal utility delta is always 220 or 440, and normal utility wye is always 208. The delta can give 120, but only on 2 legs, the wye is 110. Because of this most motors are rated at 230 and will run on either 208 or 240. Since machine shops have mostly motors they prefer delta because the motors are more powerful, and the wiring will tolerate more voltage drop. Wye is popular in offices where the 3 legs can be reduced to 110 for lighting.



In the campground 50 amp 220 situation, the neutral will indeed carry zero current if both legs of A and B comming in are exactly loaded the same. The phases are 180 out because a meter to each other is twice the meter from leg to ground and neutral. Since this is AC, when the return of the 110 on phase "A" is moving one way through the common neutral, the return of the 110 on phase "B" is moving the other way on the same neutral and cancelling it... for exactly same loads on A and B only. Again, that is why the neutral is the same wire gage size as either hot lead. The bigest load the neutral will carry is full load on 1 leg and zero on the other. I am not an electrical engineer, but this has been covered intensely on the bus conversion web sites, and I am only repeating what some experts said. After I thought about it long enough it makes sense to me.



Excellent response from Texas diesel on the generator operation too. It seems to me that the gen manufacturers go all out to make it as cheap as possible. They assume the 220 use of the gen will always be balanced and don't provide for proper voltage regulation when it is not.



Also, FYI 220 VAC is not legal in the coach or camper per RIVA, so any one making a permanant 220 installation that would be subject to an inspection will have trouble. Where 50 amp is brought into a coach, the 2 legs are never brought to the same appliance to make 220. They are always put with neutral to make everything 110. I think in some states a person making a coach into a motorhome is subject to inspection in order to convert the commercial title to motorhome and get all of the motorhome status privileges.



Doug Rees

 

[drees1]

One more comment... .



In some home appliances as mentioned, 220 only is used, so no neutral is present. This is true if the appliance has all 220 volt operation and controls, and 110 is not needed. The dryer and AC are good examples. When 110 is needed, the neutral is used with one of the hot leads to get necessary 110. An example is an electric range where the heating coils are 220, and the light bulbs are 110. That range would have 4 wires, 2 hot, 1 neutral, and 1 ground. As mentioned before, the ground is safety only and carries current only when there is a short. It protects the individual if a metal enclosure were to have a hot lead short on it. Therefore, never intentionally use a ground to carry current by design during normal use, and never defeat a ground circuit.

 

[Bill Stockard]

In the 50 Amp RV application, the RV uses only 110 Volts, but it uses a 220 volt 50 Amp four prong receptacle. The RV uses each "leg" of the 220 plug for 110 volt loads such as 2 A/C units--one connected to each leg of the 220 volt line. There is nothing in the RV that uses 220 Volts, so in what you really have is two 110 Volt systems.



I had a 35' single slideout 5th wheel with 50 AMP power cord for the 50 Amp 220 Volt connections. It had 2 roof mounted A. /C units and was wired/plumbed for a washer/dryer. The washer/dryer unit it was designed to use is the stacked apartment type Whirlpool/Sears unit that utilizes a 110 Volt dryer.



I always tried to get the 50 Amp service in RV parks, if available, since there weren't many units using 50 amp hookups at that time and there were fewer low voltage problems.



So to answer the original question, you probably could run it on the 220 Volt outlet on your generator by making a 30 Amp 220 Volt to 50 Amp RV connector, but I would NOT do it since Texas Diesel is right about the unequal loads on the two 110 volt "legs" on the generator. The 220 volt outlet on you generator is designed for 220 volt equipment.



Bill

 

[BK]

Doug, I agree with your 2nd set of comments about the cooking range and such.

But on your 1st comment your still missing the basic concept.

when a 208 (to be exact) load is put across phase A and phase B to be powered, it's not drawing current from a connection from the neutral... . and in most cases as we both agree it's not at the plug. But due to the "phasing", the currents do not cancel but do "time share the wire". So the average AC current will be slightly higher than the single phase RMS current, but no where near double the RMS current.



For Current flow to happen the electrons NEED to have a complete path of return to it's source. For phase A and phase B, that is their "neutral" wires (which are one in the same in the panel, but not brought to the load) back to the transformer. For electron flow to occur, there must be a completed path with actual flow, law of physics that can't be over come if "power" is to flow.

If the actual electrons are stalled on the wire, because two potentials are cancealing each other out... than there is no electron flow... therefor no current flow. Current flow is the flow of the "holes" left behind in an atom by the flow of the electrons to the next atom... due to difference in potential. There is current flow in the "neutral wire", back to the transformer on the pole.

 

[BK]

I'm sorry, in my ramblings at the keyboard I made a mistake in my original post about this. I think I had said that phase A and B are 90deg apart as an example... to be completely accurate, they are 120.

In a three phase system each is 1/3 of 360 (each phase is 1/3 of a 1 rotation of a generator... or of 360deg).



So when I say the neutral wires sees currents from each phase which " time shares" the wire... . each 1/3 of a "period" each phase shoot it's peak current down the wire. ( yes theres an overlap at the avg value)... Thats why the neutral wire is not any larger than the hots.



Which brings me to what I should have said in my last post...

So at no time is any phase 180deg from another phase.

If you did have two phases 180degs from one another. . you would (to cancel the current flow in the neutral wire... . ) you would have no flow through the whole curcuit and measure Zero volts across the two phases.



The reason you measure 208Vrms instead of 240Vrms across two 120Vrms phases (like you would two car batteries12+12=24) is that the two phases are out of phase. . but not opposite.



If two phases were 180deg from one another. . besides trying to explain it based on electron or hole flow... try this...

(1st in phase... )

if you take two batteries (think of freezing in time the polarity of an AC wave form)... . and hook them in series...

One way you would would "in phase"

+ battery A to load

- battery A to + of battery B

- of battery B to load...

You would have 24V...



But if you put battery B 180 degrees out of phase you would do this:

+ battery A to load

- battery A to - of battery B

+ battery B to load...

You would measure Zero volts and not light a light bulb.



The windings off of the pole transformer can be modeled very simply as batteries to explain the basic summation of voltages and current flow... More detail can be added based on their degrees of seperation for more accurate voltage modeling (why you see 208 instead of 240) and currents. . but that doesn't add to this discussion and the magic some RV maker mentions of neutral wires and dissappearing currents.



-Bob