100 amp service?? Someone educate me

[BB_TX]

Looking at the new KOA directory today. In the symbol table they have 3 symbols for power available; Max amps service 30 amps, Max amps service 50 amps, and Max amps service 100 amps. Only saw 3 locations (Baton Rouge, Chattanooga, and in Ontario Canada) that showed having 100 amp service.
Are there really high end rigs now using 100 amps? Park models maybe? Planning for our future?

[Art-n-Marge]

Make that someone educate us. I am not familiar with this availability either. I've seen television shows lately where some of the gigantic Class A units must need more than the 50 amps I'm familiar with. I hope someone can get us up to date.

[Bigboomer]

I think they really mean that with the 50 amps there are two sides of the service at 50 amps each so maybe they are adding them up to get 100. And really a lot of parks have issues with just 50 amps cannot imagine 100. With 90 amp converters I do not think our rigs could handle it.

[BB_TX]

quote:Originally posted by Bigboomer

I think they really mean that with the 50 amps there are two sides of the service at 50 amps each so maybe they are adding them up to get 100. ................

That was my first thought. But I don't think they would have separate different symbols for 30, 50, and 100 if that were the case. Each one has either 30, 50, or 100 inside the small symbol of a connector.

[rohrmann]

I went on the KOA site and went through the motions like I was selecting a site to reserve for an RV at their Baton Rouge park. The only power listed was 30/50 amp, even though they show 100 amp in the park. I think the 100 amp is for the deluxe cabins, which would make sense, as most electrical codes have 100 amps as the minimum supply for a structure like a separate large cabin. It is strange that they would even list 100 amp when it doesn't make any difference to an RV'er who's not staying in a cabin.

[bigmurf]

I believe this refers to the pedestal itself. 20+30+50= 100. I have seen this description used in some electrical publications. Just some good old BS to make things look good. IMHO

[Art-n-Marge]

Bigmurf.. but why would the KOA then only show just 2 or 3 of these 100amp types if there are many more 50 amp. You think that some of the 50 amp do not have the 20 and 30 amps? Again, I prefer not to guess. Maybe I'll just call them and ask.

[DQDick]

Here's your answer, just a new way of stating what I've already put in my home base: http://www.electricalmaterialscompan...100a_metrd.htm I've seen more and more three AC class A's over the last year, however, so it shouldn't be too long before someone will be plugging into this baby with some type of strange cord or cheater set up to get more power out of it than just the 50amps.

[rohrmann]

If that logic were used, adding all the plug amps, you would have 200 amps from that meter. No one makes a meter socket less than 100 amp rated anymore. That socket is a four jaw configuration, two line side jaws and two load side jaws, each line/load side capable of 100 amps. Many newer parks have that style panel. A 50 amp RV outlet has two separate 50 amp legs, still only called 50 amp. The 20 amp and the 30 amp outlets are both single hot leg outlets, so that panel is not set up to pull 100 amps on both hot legs. The 20 amp is probably on the one leg and the 30 amp is on the other leg. It will be interesting to hear what KOA is claiming the 100 amp symbol is for.

[Phil P]

Hi

First the key words in the link provided by DQDICK are “temporary service equipment” in the last line of the initial description. When used as a temporary service unit on a construction site it would not be uncommon to have several subcontractors using all three outlets at one time so the unit is capable of delivering 100 amps continuous.

This constitutes a 125 /250 volt 100 amp service.

Now I will try to explain what looks like a misconception on the part of some people.



This is an electrical drawing of a 200 amp transformer like the power companies use on the pole outside your home or in a cabinet on the ground in an underground service.

The 50 amp 120 / 240 volt “service” provided at RV parks have a single compound circuit breaker with the capability of delivering 50 amps on one of the 2 lines at 120 volts.

We will call this 50 amps on line 1. Line 1 is using the neutral or center line in the drawing for its return to the transformer. If you put an Amprobe test meter on line 1 and neutral it would read 50 amps on both wires.

Now we will add a 10 amp load on line 2. If you put a third Amprobe meter on line 2 it would read 10 amps but the meter on the neutral would still read 50 amps and the meter on line 1 would read 60 amps. This is the result of the neutral being common to both line 1 and line 2 so the added load on line 2 appears to the electrical circuit as a 240 volt load and uses line 1 for its return to the transformer.

If the circuit is protected by a 50 amp compound breaker then the breaker would trip because the load on one side had exceeded the breaker capacity.

Now to further illustrate this lets put a 25 amp load on line 1 and a 25 amp load on line 2. The meters would read 50 amps on line 1 and 50 amps on line 2 and 0 amps on natural.

The result is a 50 amp 120 /240 volt service will only delivery 50 amps if the circuit is protected by a 50 amp circuit breaker.

I am sure this is as clear as mud but I gave it a good try.

Phil P

[WaltBennett]

Notwithstanding how 50 amp service can be described, I wonder if those three parks don't have TWO separate 50 amp circuits just for those big Prevost type RVs. From what I've seen on one of them, they could be wired for that. One had a generator the size of my truck engine (200kv I think). There's "Extreme RVs", the TV/cable show that sometimes has them, but even if I had the $$ I don't think I'd be in the market.

[Phil P]

quote:Originally posted by WaltBennett

Notwithstanding how 50 amp service can be described, I wonder if those three parks don't have TWO separate 50 amp circuits just for those big Prevost type RVs. From what I've seen on one of them, they could be wired for that. One had a generator the size of my truck engine (200kv I think). There's "Extreme RVs", the TV/cable show that sometimes has them, but even if I had the $$ I don't think I'd be in the market.

Hi

All the park would have to do to make that box a 100 amp service is put a 100 amp circuit breaker in place of the 50 amp circuit breaker provided the park wiring would support a 100 amp load. This is what a construction company would do when using that box for a temporary service. I am sure the receptacle would have to be changed to use 100 amps as well.

I would assume if the park has the new box the park would be wired for 100 amps to each box.

Phil P

[BB_TX]

quote:Originally posted by Phil P

............
Now to further illustrate this lets put a 25 amp load on line 1 and a 25 amp load on line 2. The meters would read 50 amps on line 1 and 50 amps on line 2 and 0 amps on natural.
......

I am going to have to disagree with you on this one.

If you put a 25 amp load on line 1 with nothing on line 2, then you will read (with a meter) 25 amps flowing thru line 1 and 25 amps thru the neutral wire.

If you put a 25 amp load on line 2 with nothing on line 1,then you will read 25 amps flowing thru line 2 and 25 amps thru the neutral wire.

But if you put 25 amp load on both line 1 AND line 2, then you will measure 25 amps flowing thru line 1, 25 amps flowing thru line 2, and no current thru the neutral wire. This is because any current that may have flowed out the neutral wire is diverted thru the other hot line due to the opposite polarity, i.e. when line 1 is positive line 2 is negative and vice versa.

If you put a 25 amp load on line 1 and a 10 amp load on line 2, then you would read 25 amps on line 1, 10 amps on line 2, and 15 amps on the neutral wire. That is because one 10 amps of line 2 gets diverted from the neutral.

You can't put a 25 amp load on one line and read it as 50 amps, no matter how much current is flowing thru the other line.

[Phil P]

quote:Originally posted by BB_TX

I am going to have to disagree with you on this one.

If you put a 25 amp load on line 1 with nothing on line 2, then you will read (with a meter) 25 amps flowing thru line 1 and 25 amps thru the neutral wire.

If you put a 25 amp load on line 2 with nothing on line 1,then you will read 25 amps flowing thru line 2 and 25 amps thru the neutral wire.

But if you put 25 amp load on both line 1 AND line 2, then you will measure 25 amps flowing thru line 1, 25 amps flowing thru line 2, and no current thru the neutral wire. This is because any current that may have flowed out the neutral wire is diverted thru the other hot line due to the opposite polarity, i.e. when line 1 is positive line 2 is negative and vice versa.

If you put a 25 amp load on line 1 and a 10 amp load on line 2, then you would read 25 amps on line 1, 10 amps on line 2, and 15 amps on the neutral wire. That is because one 10 amps of line 2 gets diverted from the neutral.

You can't put a 25 amp load on one line and read it as 50 amps, no matter how much current is flowing thru the other line.

You are correct that’s a typo error. Sorry for the error.

The point is you cannot get 100 amps from a 50amp 220 volt service that is supplied to the RV.

Line 1 50 amps line 2 50 amps neutral 0 amps is still only 50 amps not 100 amps as stated by some of the people on this forum.

You don’t add the 2 together as I did in my typo error.

Phil P

[BB_TX]

Again I will have to disagree, although it may just be semantics.

You can have 50 amps flowing thru line 1. And at the same time you can have 50 amps flowing thru line 2. So at maximum current flow thru both lines at the same time you can have 12,000 watts of power (100 amps x 120 volts = 12,000 watts).

You can't have more than 50 amps flowing thru either hot leg or any wire at any time. And (at any given time) the current flowing into one leg is flowing out the other leg. So in that respect it is not additive. But you do still get the EFFECT of having a total of 100 amps IF you have loads that would draw the maximum of 50 amps from each hot leg at the same time. The 50 amp breaker is a double pole breaker, each pole rated for 50 amps. Since the hot legs are not additive, you can have up to, but not more than, 50 amps flowing thru each pole and to each separate group of loads simultaneously.

[rohrmann]

That is correct, 100 amps total capacity, using two 50 amp breakers. They are 120 volt legs, each supplying 50 amps. I was thinking about this last night after my previous post, can you imagine how large the cable would have to be to supply a 100 amp/4 wire electric service? You almost would have to have four separate cables instead of one four wire cable to be able to move them, and they would have to be direct connected to lugs in the panel and the RV.

[Art-n-Marge]

Now that's what I'm looking for Walt. That makes sense. I checked the KOA website and those locations in the OP only state 50 amp max and no 100 amp max so I cannot confirm what they mean.

I wish someone with the guide (BB_TX) would just call them and ask what they mean by 100 amp max. All this other beer mug conversations miss the point that the KOA locations differentiate a 50 amp and a 100 amp, electrical properties aside, otherwise there doesn't need to be a difference. I might believe some of these RVs might require two 50 amp connectors and the RV is wired accordingly. If that's the case, it's odd only these few KOA locations are the only ones in the KOA directory that can support them.

This has me so intrigued, DW and I have a week long trip up to the Lake Minden Thousand Trails just north of Sacramento starting tomorrow and we're staying in one of their camping trailers (no need to tow). On the way up or back, I'm just gonna have to stop by a KOA and take a look at this new directory, then call the place that has these to find out what they mean. Then we'll all know that Walt is brilliant because he's correct. We already know Phil P is a smart guy from that electrical description but I don't think that's what the KOA directory means. I'll still be dumb as stones but I do know how to research. As for Lake Minden if you are in the area, stop by and we'll have a beer cuz I think I might have the answer to share (okay, I'll share the beer, too).

[rohrmann]

KOA online directory, exactly like the print version--
http://koa.uberflip.com/i/268207

[mtheo]

I hate to disagree with some of you, but from what I know. With 50 amp 240volt, You have two hot legs and a neutral. Power comes in on the hot and out the neutral, not out the other leg, other whys you would have 240 volts. Just like on a 30 amp service you have one hot and a netral, power comes in on one and out on the other.

[BB_TX]

quote:Originally posted by mtheo

I hate to disagree with some of you, but from what I know. With 50 amp 240volt, You have two hot legs and a neutral. Power comes in on the hot and out the neutral, not out the other leg, other whys you would have 240 volts. Just like on a 30 amp service you have one hot and a netral, power comes in on one and out on the other.

You have to understand exactly how the current flows when you have two hot legs out of phase.
When you have a load on leg 1 and no load on leg 2 you have current flow from the hot and to the neutral on the positive part of the cycle, and current flow from the neutral and to the hot on the negative part of the cycle. Just like the voltage alternating, the current also alternates direction each cycle.
Now take leg 2. It is in opposite phase of leg 1 meaning when leg 1 is in the positive part of the cycle (current flowing from hot to neutral), leg 2 is in the negative part of the cycle (current flowing from neutral to hot).
The voltage in each hot leg is 120 volts with respect to neutral. But since the two hots are opposite phases, the voltage is 220 with respect to the other hot. That is how you can get both 120 and 220 volts from one source.
Now back to the current flow. When there is 10 amp load on hot 1 there is a current flow of 10 amps from hot 1 to neutral on the positive part of the cycle.
If there were a simultaneous 10 amp load on hot 2 there would be a current flow of 10 amps from neutral to hot 2 since it would be on the negative part of the cycle. Just the opposite direction of hot 1.
Now if there is 10 amps flowing from hot 1 to neutral at the same time there is 10 amps flowing from neutral to hot 2, the current is not going to flow thru neutral at all since they have a common neutral. The current from the hot 1 line that would have gone to neutral will instead be diverted to the hot 2 side since it has current flowing from neutral to hot. You can't have current flowing both directions thru the neutral wire at the same time.
Clear as mud, huh?