50 amp to 30 amp stepdown.

hershey wrote:
Its funny how we tend to pick a statement apart, word by word in order to find a fly in the ointment.
Yes, technically the 50/30 adapter is not a step down in voltage but a step down in that a 30 amp RV can plug into a 50 amp shorepower.
Yes, you indeed do get a full 50 amps of power to your RV and this is technically not legal because of the size of wiring that the dogbone is connected to going to your RV. Yet, that 50 amp once it reaches your RV is completely protected by your 30 amp RVs electrical setup. So if there is any overloading possibilities, its only going to be in the power cord to from the RV to the dogbone adapter.
Since the 30 amp RV is only going to use potentially 30 amps, even that power cord will never see a draw of over 30 amps so its pretty much a wash.
Bottom line? Use the dogbone if you like, or plug directly into the 30 amp receptacle at the post. And don't get confused by the nit-pickin' over something as trivial as this legitimate question.

It doesn't deliver 50 amps :)

It can carry 50 amps if something is turned on that uses 50amps :)

But as mention a "30 amp" RV will only push up to 30amps through the circuit.

hershey wrote:
Its funny how we tend to pick a statement apart, word by word in order to find a fly in the ointment.
Yes, technically the 50/30 adapter is not a step down in voltage but a step down in that a 30 amp RV can plug into a 50 amp shorepower.
Yes, you indeed do get a full 50 amps of power to your RV and this is technically not legal because of the size of wiring that the dogbone is connected to going to your RV. Yet, that 50 amp once it reaches your RV is completely protected by your 30 amp RVs electrical setup. So if there is any overloading possibilities, its only going to be in the power cord to from the RV to the dogbone adapter.
Since the 30 amp RV is only going to use potentially 30 amps, even that power cord will never see a draw of over 30 amps so its pretty much a wash.
Bottom line? Use the dogbone if you like, or plug directly into the 30 amp receptacle at the post. And don't get confused by the nit-pickin' over something as trivial as this legitimate question.

Excellent explanation.

diveman52 wrote:

Johno02 wrote:
You can draw 50A of power through a 50 to 30 adapter that is plugged into a 50A plug with a 50A breaker, IF you have a 50A load. Until the adapter get hot and burns up. The wire does not limit the current draw until it fails. You will get voltage drop, then overheating.

How in the world can you do that when the RV has a 30 amp main breaker?

You can't., but it's a great example of how little is understood about 30A, 50A, and RV electrical systems.

If the trailer is set up for 30A service, the power cord is going to be limited to 30A and will be protected regardless of what outlet you are plugged into. Now, if you have a 50A trailer and are plugged into a 50A service, then a 30A cord would likely burn up, but to do that you would have to be using an adapter on both ends, and who is going to bother with that? No, I take that back, there people who would do that just to not have to deal with the 50A cord. Those people, we can not help here.

Its funny how we tend to pick a statement apart, word by word in order to find a fly in the ointment.
Yes, technically the 50/30 adapter is not a step down in voltage but a step down in that a 30 amp RV can plug into a 50 amp shorepower.
Yes, you indeed do get a full 50 amps of power to your RV and this is technically not legal because of the size of wiring that the dogbone is connected to going to your RV. Yet, that 50 amp once it reaches your RV is completely protected by your 30 amp RVs electrical setup. So if there is any overloading possibilities, its only going to be in the power cord to from the RV to the dogbone adapter.
Since the 30 amp RV is only going to use potentially 30 amps, even that power cord will never see a draw of over 30 amps so its pretty much a wash.
Bottom line? Use the dogbone if you like, or plug directly into the 30 amp receptacle at the post. And don't get confused by the nit-pickin' over something as trivial as this legitimate question.

Johno02 wrote:
You can draw 50A of power through a 50 to 30 adapter that is plugged into a 50A plug with a 50A breaker, IF you have a 50A load. Until the adapter get hot and burns up. The wire does not limit the current draw until it fails. You will get voltage drop, then overheating.

How in the world can you do that when the RV has a 30 amp main breaker?

One thing I've tried with mixed result is De-Ox-It. Sometimes it might help make a solid connection, sometimes the receptacle is just too far gone for it to be of any use, especially if it is semi-burnt.

wa8xym has it right.

"Step-down" is not the correct term in the electrical industry for current. "Adapter" is the word to use. Transformers are called step down (or step up) because they transform voltage. When you go to buy one, you'll never see the term step-down used or on the package.

30A receptacles in pedestals generally get used a lot more than 50 amp ones. Many people do NOT turn off the breaker at the pedestal and the contacts inside the 30 amp recept. can get pitted and dirty leading to high resistance. Also, a lot of use and abuse can lead to poor contact pressure inside the recept., also contributing to high resistance. Pitting and poor contact pressure can result in overheating and a meltdown. If a pedestal looks to be in rough shape and/or you need a stick to make the cord stay plugged in, switch to a 50A if the pedestal has one and use your adapter. Or find another site.

An adapter *could* protect your cord if there ever was a meltdown. The plug and part of the adapter only might get damaged instead of the cord itself.

The chances of having a short in your power cord are very, very low and a short would trip the 50A breaker anyway. The 30A breaker in your RV will limit the current draw to 30 amps. The 30 up to 50 amp adapters are used a lot. We carry one in case we encounter a 30A pedestal in sad shape.

As a side note, remember - always, always shut the pedestal breaker off first (or inside your TT) before plugging in to the pedestal. Then turn it on. If the blades on your shore power cord look dirty or pitted, clean them until bright metal.

This is the type of pedestal you hope you never have to use. We stayed in a large CG last summer and they were all like this. Old and not maintained. This was one where I had to use a stick to keep the cord plugged in. We kept loads to a minimum to reduce the chances of overheating. One of the projects on my to do list is to make a 30A to 30A dogbone adapter in case the plug at the adapter ever went up in smoke if we ever have to plug into another pedestal like this.

I use the 30A, but if it is shorted or burned out, out comes the 50A dogbone. What would be nice is if someone can make a 30A cable with a SWD rated circuit breaker inline. That way, there is always a guarentee of 30A protection regardless of how many amps the circuit it is plugged into has.

Fist it is not a "Step Down" it is an adapter (There is a technical difference)

Now: To answer your question: Any advantage to using the dogbone adapter and plugging into 50 amps.

Answer: Sometimes. Two of them

Advantage ONE: in many parks/sites the 30 amp outlets are in far worse shape than the 50's this may be due to the amount of use or it may be due to other things I do not care to go into since it's "Suspect" not Confirmed.

Advantage 2: Depends a bit on your RV.. If your main breaker panel is inside and easy to get at, you have a 30 amp main breaker,, Now if you turn on too manuy thigns (A/C, Electric Water Heater and Microwave for example) on a 30 amp outlet you got to get dressed, go outside and re-set.. If you are plugged in via a dogbone to the 50 amp.. You do not have to get dressed or go outside (let's make it nice and say it's raining) to reset,,, just reset INSIDE.

Disadvantage:

Some folks like to point out that the main breaker inside does not protect your 30 amp cord and they are correct.. but there are two kinds of short circuits, A Dead short (Like a crowbar across the terminals) and a partial short.

A dead short will pop a 50 or even a 100 amp breaker (or larger) before a 30 amp cord melts, and a partial short that is just enough to take out the cord without taking out the 50 amp breaker is ... Theoretically possible but I for one have never seen such a thing and do not believe I ever will.. The odds approach zero.

You can draw 50A of power through a 50 to 30 adapter that is plugged into a 50A plug with a 50A breaker, IF you have a 50A load. Until the adapter get hot and burns up. The wire does not limit the current draw until it fails. You will get voltage drop, then overheating.