Park pedestal wiring

Stolen from one of RoyB's posts:

bob213 wrote:
Just wondering if anyone knows the typical wiring for a park pedestal. My question is...Is the 30 amp outlet run off the same wiring as the 50 amp just with a smaller breaker and single hot? If I use the 50 amp with a 30 amp pigtail and then use the 30 amp with a 15amp pigtail am I stealing power from my own 50 amp feed?
We are going to be camping in 110* degree temps and thought I would try and distribute power usage by running things off all the available outlets. Am I fooling myself?

What are you trying to accomplish? Not all pedestals are wired the same. If you have a 50 amp rig, there should be no need to do anything, there would be plenty of power available to run anything and everything. If you have a 30 amp rig, even using the 50 amp receptacle, you will still be limited by the 30amp main breaker in your rig. If you have a 30 amp rig and are wanting to also us another receptacle to power some item using extension cords and the like directly to that item, you probably can get more power, but not always.
You need to be careful adapting down to a higher amperage receptacle if there is no circuit breakers in the line, because it is possible to overload the extension cords and cause a fire.
I have seen some people take a 30 amp rig, adapt it down to 20 amps, use a cheap extension cord and then adapt back up to 30 amps at the receptacle. Guess they thought they were either being economical (the dollar store extension cord is cheaper than a good 30 amp extension cord) or thought it was easier to move around that cheap cord than the heavier 30 amp one. The results are pretty predictable, they turn on a high amp appliance, cheap cord melts and there is either a direct short tripping the breaker at the pedestal (bad, but not real bad) or a fire starts.
Bottom line is without knowing what you have as far as a rig and what you are attempting to do, a definitive answer will elude us all.

bob213 wrote:
Am I fooling myself?

50 amp RV service is 50 amps across each of two legs for a total of 100 amps or 12,000 watts. Using a standard 50 amp male > 30 amp female dogbone allows you to draw from just one of those 50 amp legs but I suppose you could use a 50 amp male > dual 30 amp female dogbone adapter which will draw from both legs of that 50 amp service ... that's not enough?

The exact details can and do vary some.

Frequently (but doubtless not universally), the entire pedestal is limited to 50A maximum from any combination of the receptacles. The 30A and 20A breakers are fed from single legs of the 50A feed, with the 50A breaker being a main breaker for the pedestal as a whole.

DrewE wrote:
Frequently (but doubtless not universally), the entire pedestal is limited to 50A maximum from any combination of the receptacles. The 30A and 20A breakers are fed from single legs of the 50A feed, with the 50A breaker being a main breaker for the pedestal as a whole.

Since so-called "50 amp RV service" is in fact 100 amp service because it's 50 amp across each of two legs any pedestal wired in this manner would offer a minimum 100 amp service, not 50.

Usually these are daisy chain on 200+ amp circuit. All pedestals have full power available to all outlets. You will not hurt the pedestal. Most places frown on multiple cords into the RV.

SoundGuy wrote:

DrewE wrote:
Frequently (but doubtless not universally), the entire pedestal is limited to 50A maximum from any combination of the receptacles. The 30A and 20A breakers are fed from single legs of the 50A feed, with the 50A breaker being a main breaker for the pedestal as a whole.

Since so-called "50 amp RV service" is in fact 100 amp service because it's 50 amp across each of two legs any pedestal wired in this manner would offer a minimum 100 amp service, not 50.

The 50A RV service is 50A 120/240V split phase service. It is not a 100A service in any sense, although it does supply the same power as a 100A 120V single phase service would supply (12 kW in both cases). You cannot power a device requiring 100A (such as, say, a 12 kW 120V light bulb, if you somehow happened to have one) directly from the 50A RV receptacle. You could power a 12 kW 240V light bulb, of course, if you had one, at least until your neighbors complained and the campground management demanded you turn it off.

It's the same situation when comparing a 12V DC system with a 24V DC system. A 5A 24V circuit can supply the same power as a 10A 12V circuit, but that does not make it a 10A circuit in any sense. Adding a grounded center tap doesn't change this.

DrewE wrote:
Frequently (but doubtless not universally), the entire pedestal is limited to 50A maximum from any combination of the receptacles.

SoundGuy wrote:
Since so-called "50 amp RV service" is in fact 100 amp service because it's 50 amp across each of two legs any pedestal wired in this manner would offer a minimum 100 amp service, not 50.

DrewE wrote:
The 50A RV service is 50A 120/240V split phase service. It is not a 100A service in any sense, although it does supply the same power as a 100A 120V single phase service would supply (12 kW in both cases).

You're splitting hairs over definition ... I've simply pointed out that your declaration "the entire pedestal is limited to 50A maximum from any combination of the receptacles" is inaccurate since the total potential draw from 50 amp RV service is in fact 100 amps (12,000 watts) - i.e. 50 amps / 6,000 watts per 50 amp leg.

OP, you are only using 45 amps out of a total of 100+ as the wires to the pedestal should be large enough to handle the 100 A on the four lug outlet (50 A service X2) plus the 30 A and even an additional 15 A when there is a third outlet... a total of 145 amps.

To answer your question: YES. exactly same for the 20 though it MIGHT be the other leg.. Or not.