50 amp more reliable?

[Bones2003]

For what its worth, here's what I do with my 30A RV. I generally assume that the electricity to the post is the same quality regardless if it is the 15A, 30A, or 50A outlet. Therefore the next thing I look at is the quality of the connection. I always use a 3 prong electrical outlet tester to check for miswires or open wires at the outlet. I also wiggle it around looking for loose or intermittent connections. The third thing I do is look at the outlet for obvious burns or cracks. If all is well, I turn off the 30A breaker at the post, plug in my cord, and turn the breaker back on.

Of the several hundred times I've connected to campground power over the years, I've only found 2 or 3 with problems. One just had no power so I moved to another site and on another one I used a 50A to 30A adapter with no problems. Finally on one I used a 15A to 30A adapter with no problems (but we were careful not to use too many appliances at once in the RV).

Luckily, we have never had a breaker trip in the post or the RV. It tends to be just my wife and I so we generally don't have too many things running at once. I imagine an RV loaded with a bunch of teenagers plugging in who-knows-what could be a problem.

[Goodspike]

Originally Posted by orangeminnie

125v x 30A = 3750 watts
===
This weird dogbone assumes that the 15A outlet is on a separate circuit from the 30A outlet.
You're right that it's just the luck of the draw if the side that gets the 15A service would be the side that you use less load. Turn on both your ACs, and then a microwave, and see what pops.

I would assume most RV park setups have heavy gauge cables running to the pedestal breaker box, and that one set of cables connects to all the outlets through the separate breakers. If so and it has a 50 amp plug then it could handle both the 30 and 15 outlets being drawn on at the same time at their rated capacities (e.g. a trailer and electric car). I don't know about drawing on the 50, 30 and 15 at the same time. That might be a stretch, sort of like in your house system the main breaker would pop if you somehow managed to use the rated amperage on all the various circuits in the house.

[Goodspike]

Originally Posted by Bones2003

For what its worth, here's what I do with my 30A RV. I generally assume that the electricity to the post is the same quality regardless if it is the 15A, 30A, or 50A outlet. Therefore the next thing I look at is the quality of the connection. I always use a 3 prong electrical outlet tester to check for miswires or open wires at the outlet. I also wiggle it around looking for loose or intermittent connections. The third thing I do is look at the outlet for obvious burns or cracks. If all is well, I turn off the 30A breaker at the post, plug in my cord, and turn the breaker back on.

Those sound like good practices, and yes the "quality" should be the same, so it is the outlets and breakers that could make a difference. I do check also that it says 30 amp on the breaker, and either 15 or 20 if I'm going via that connection.

I bought this 30 amp surge protector, not so much for the surge protector but because it not only has the lights to show a proper connection, it will connect to your phone via Bluetooth and give you voltage and draw information. Unless I'm going to be running my AC (or get some lower voltage reading) I don't leave it connected.

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

[Phil G.]

Originally Posted by Goodspike

I agree with Creativepart. Although 50 is higher than 30, you're really only getting one leg of the 50, so in theory if it were actually a completely separate line (which it probably isn't) you're only going to get 25 amps. You probably would trip the breaker earlier with the 50 because drawing at or near 25 would trip it. The 30 is the way to go.

(I'm the OP.)

So .... if I use my 50A-to-30A adapter to power my 30A motorhome .... are you saying that I really only have 25 total amps of power available for use because the adapter is really only connected to one of the 50 amp service's 25 amp legs?

If so, what if I want to run the A/C and the microwave at the same time in my 30 amp motorhome? Worse yet, in cold weather what if I want to run two 1500 watt electric heaters at the same time in order to save furnace propane? One time (in terrible humidity but moderate outside temperature conditions) I ran both the A/C and an electric heater at the same time in order to keep coach humidity down simultaneous with keeping coach temperature up.

One condition in which I thought that using a 50A-to-30A adapter to power our 30A RV would be superior was due to what I've read about campground power sags during hot weather when too many RVs were using their air conditioners. I thought by using the adapter that maybe I would not experience power sag in our 30 amp RV.

[SummitPond]

Originally Posted by Phil G.

(I'm the OP.)

So .... if I use my 50A-to-30A adapter to power my 30A motorhome .... are you saying that I really only have 25 total amps of power available for use because the adapter is really only connected to one of the 50 amp service's 25 amp legs?
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Each leg has 50 amps, it's not split 25-25. So in reality a unit that takes 50A service is capable of drawing 12,000 watts compared to a 30A unit's 3,750 W.

I have a 50A to 30A dogbone, but use it only when there is no 30A service on the pedestal. As odd as it seems, I've run across a few campgrounds with this arrangement, and even some with no 15A outlet - which forces the issue.

The concern that has been raised is that the pedestal's breaker won't trip if you exceed 30A draw for your MH and you rely strictly on the breaker in your unit.

[Bones2003]

Phil G.
That is not correct. The 50A connection at the campground pedestal has two "legs" that are each rated 50A. When you use a 50A to 30A adapter, you are simply connecting up to one of those "legs". Therefore, you have 50A available from the pedestal through your 30A cable going into your RV to the main RV 30A circuit breaker. That main breaker in the RV limits the amount of current to 30A going to everything in your RV.

EDIT: Note, this is the concern about safety that some people have mentioned. Your 30A cable and 30A wiring inside your RV that goes to your main 30A RV circuit breaker are not designed to handle 50A. With a 50A to 30A adapter, that cable and internal wiring are not protected from 50A if there is some type of fault.

Regarding power sags; the 30A breaker in the pedestal is probably wired into one of the 50A "legs" either in the pedestal or back further by the RV park main power system so the sags will more or less be on all the circuits. A lot depends on how the power distribution system at the RV park was designed, built, and maintained.

If you are worried about sagging voltage, I recommend you buy a small voltage meter that plugs into an outlet so that you can actually see if the voltage in your RV is sagging.

[Goodspike]

Originally Posted by Phil G.

(I'm the OP.)

So .... if I use my 50A-to-30A adapter to power my 30A motorhome .... are you saying that I really only have 25 total amps of power available for use because the adapter is really only connected to one of the 50 amp service's 25 amp legs?.

That's what I originally said, but I corrected it. I was assuming a different breaker system because I've never connected to the 50 amp portion and never looked at one.

What I'm now saying is you're creating an unsafe condition because you're connecting a system only designed for 30 amps up to a breaker that won't trip until 50 amps. It's a fire risk. And for no benefit because the "quality" of the electricity would be the same (unless the outlet is damaged or breaker defective).

[Goodspike]

Originally Posted by Bones2003

If you are worried about sagging voltage, I recommend you buy a small voltage meter that plugs into an outlet so that you can actually see if the voltage in your RV is sagging.

That device I linked above will do that, and you can even set alarms that will sound on your phone if the voltage goes above or below a certain limit. Of course you need to be within bluetooth range of that device.

It will also tell you if the outlet is not wired or grounded properly.

Edit: Here's the link again.

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

[Phil G.]

Originally Posted by Goodspike

That's what I originally said, but I corrected it. I was assuming a different breaker system because I've never connected to the 50 amp portion and never looked at one.

What I'm now saying is you're creating an unsafe condition because you're connecting a system only designed for 30 amps up to a breaker that won't trip until 50 amps. It's a fire risk. And for no benefit because the "quality" of the electricity would be the same (unless the outlet is damaged or breaker defective).

You make a valid point that if - when using my 50A-to-30A adapter to power our motorhome - my motorhome's main internal 30 amp circuit breaker fails to trip then I have no "backup 30 amp circuit breaker" in the pedestal to open the circuit in the event that my motorhome for some reason is asking for more than 30 amps of power through it's power cable.

But doesn't the same situation present itself in our homes with all the little unfused - but capable of catching fire - items that we plug into 15A or 20A wall receptacles? For what it's worth, we unplug most all 120V items from their wall receptacles in our home whenever we leave it.

I'm still not sure that both legs of campground 50A power are sagged equally whenever too many 50A RVs are using their air conditioners - maybe only one leg could be sagged but not the other? I wonder which leg of 50A service my 50A-to-30A adapter uses to provide 30 amps of power to my motorhome?

[Morich]

Lots of theory and lots of it is correct but then when we look at what really happens it tends to change the potential for a problem. Breakers in camp grounds go dead reasonably often but it is also more often for me to find mine dead because somebody else on the line has a problem. I do keep a 50 to 30 adapter and I have used it but I also know that I will very, very rarely hit using 30 amps at the same time. One point being what features are normal on 30 amp RV. I don't see them with two aC to run, nor any other large power hogs. We can create a hazard if we do work at it by adding 1500 watt heaters amd making sure we run them on different circuits within the RV and then also running the AC. But that does take some really careless action and does mean we are working outside the design.
So, yes I do agree that we can build a bad situation but the dogbone adapter will only be part of our effort to shoot ourselves in the foot!
The normal user and history say the dogbone is not a big enough hazard to worry about but it does make good stuff for bloggers, etc. to write about. To sell adverts, one has to keep traffic up and to do that, one has to have something really unusual and exciting to post!
Ever wonder why the weather lady gets just totally breathless even when it a clear and sunny day? Same reason! Got to have something to sell.

[Bones2003]

Originally Posted by Phil G.

I'm still not sure that both legs of campground 50A power are sagged equally whenever too many 50A RVs are using their air conditioners - maybe only one leg could be sagged but not the other? I wonder which leg of 50A service my 50A-to-30A adapter uses to provide 30 amps of power to my motorhome?

Phil G.
It is safe to say that both legs of a campground 50A power will never sag equally. It is always changing as the load changes. On a 50A RV, the front air conditioner is probably on one leg, the rear on the other, etc. For the 30A circuits throughout the RV park some will be on one leg and some will be on the other. Multiply that by all the RVs in the park. Every time someone (or something) in an RV turns something on or off, the electrical load changes. About all you can do is monitor the voltages with some type of meter and turn your stuff off if it sags too much. As I talk to many people in RV parks, I would say that the majority of people don't really worry too much about it.

Your adapter is wired to always use one leg. But you never know how the pedestal is wired - is leg A on the right side of the connector or leg B? It's a 50-50 chance either way!

[Phil G.]

Originally Posted by Bones2003

Phil G.
It is safe to say that both legs of a campground 50A power will never sag equally. It is always changing as the load changes. On a 50A RV, the front air conditioner is probably on one leg, the rear on the other, etc. For the 30A circuits throughout the RV park some will be on one leg and some will be on the other. Multiply that by all the RVs in the park. Every time someone (or something) in an RV turns something on or off, the electrical load changes. About all you can do is monitor the voltages with some type of meter and turn your stuff off if it sags too much. As I talk to many people in RV parks, I would say that the majority of people don't really worry too much about it.

Your adapter is wired to always use one leg. But you never know how the pedestal is wired - is leg A on the right side of the connector or leg B? It's a 50-50 chance either way!

I wonder if anyone sells a 50A-to-30A adapter with a switch built into it so that I could switch it's 30A feed into my motorhome to whichever 50A leg on the pedestal shows the highest 120V AC voltage reading? That way on a hot day, I could make sure my motorhome was experiencing the least amount of sag at that particular time for best performance of our - for instance - air conditioner?

(I'm just trying to get around having to buy an expensive power conditioner for my 30A motorhome that will be needed only very occasionally.)

[jerichorick]

Originally Posted by Phil G.

When camping on hookups with our 30 amp motorhome, if we happen to be on a combination 30A/50A pedestal, I tend to use a 50A-to-30A adapter, plug the motorhome's 30A cable into the adapter, and then plug the adapter into the pedestal's 50A outlet.

My idea being that the pedestal's 50A power might be a more reliable and less trouble-prone way to access 30A power for the motorhome than using the pedestal's 30A outlet.

Does this reasoning and practice make any practical sense ... or is poor campground 30A power likely to mean that the campground's 50A power is also suspect?

I'll try to make this simple.


When a pedestal has a 50/30/20 outlet group, it is fed by a 100A breaker from the service panel if wired correctly. The wire size must be correct also to accommodate the load. If you can believe it () many camp grounds take shortcuts and use a 70A breaker and smaller wire, figuring only the 50A or 30A outlet will be used - not both at the same time.


If the service panel breaker, wire, pedestal breaker and outlet are all in good condition your 30A requirement will be satisfied from the 30A outlet just as well as with the 50A outlet.


For us with 50A rigs, we actually have 100 amps of power available to us. A 30A service is just that. 30 amps. Plugging your 30A service into the 50A service means you COULD, under the trip failure of your internal breaker , damage your cord and plug if you pulled too much current from the 50A service.



Hope this all makes sense. Happy trails.
Rick

[Morich]

A point that we may be missing is that power is not always going to be the same as there are lots of variables involved and they are not all created by the wiring and work at the park, nor the users at that park.
Small town systems are kind of famous for letting the power voltage swing high and low as they are sometimes using really old control equipment.
Thinking of some systems, I have seen rural systems where the power sets there pretty steady all day but when a bunch of milk coolers kick on at milking time, the voltage can swing way low. That can be caused by auto controls which are slow to react or simply a manual system where the guy watching is out of the room. They sometimes set a somewhat close setting and assume that it won't bother too many if it goes a bit high or low.
It bothered me personally because that low voltage would sometimes come in about sunrise in the summertime and that set off the alarms on the 48 Volt power plants I was supposed to maintain. Made my boss think I was not doing it right if it went off three days in a row.
The big point might be that there are things that vary and most of the time we never know it and the equipment is built to take the change. With so many simple digital readouts on different stuff, we get lots more info than we need at times. Power may be one of them.

[Goodspike]

Originally Posted by Phil G.

You make a valid point that if - when using my 50A-to-30A adapter to power our motorhome - my motorhome's main internal 30 amp circuit breaker fails to trip then I have no "backup 30 amp circuit breaker" in the pedestal to open the circuit in the event that my motorhome for some reason is asking for more than 30 amps of power through it's power cable.

But doesn't the same situation present itself in our homes with all the little unfused - but capable of catching fire - items that we plug into 15A or 20A wall receptacles? For what it's worth, we unplug most all 120V items from their wall receptacles in our home whenever we leave it.

I don't think the home analogy works because each circuit in your house is on it's own breaker. I hadn't thought of the possibility of your 30 amp breaker failing to trip. I was more concerned with what's between your 30 amp breaker and the 50 amp breaker, and that includes at least some wiring within your RV.

As to the things inside your house, the most dangerous things are the extension cords people sometimes use. Those catch fire with some regularity, and the reason is exactly the same as what I'm concerned about--having a wire of too light of gauge for the breaker protecting it. The solution to that problem is relatively simple and cheap, but government has not mandated a minimum gauge for extension cords. Yes there is some risk from things like lamp cords, but those don't tend to get overloaded, although they might be damaged. But yes, devices can cause fires too. Toasters and coffee pots are good examples. Guess which devices I keep unplugged in my house when not in use! ;-)

[Goodspike]

Originally Posted by Morich

Lots of theory and lots of it is correct but then when we look at what really happens it tends to change the potential for a problem. Breakers in camp grounds go dead reasonably often but it is also more often for me to find mine dead because somebody else on the line has a problem. I do keep a 50 to 30 adapter and I have used it but I also know that I will very, very rarely hit using 30 amps at the same time. One point being what features are normal on 30 amp RV. I don't see them with two aC to run, nor any other large power hogs. We can create a hazard if we do work at it by adding 1500 watt heaters amd making sure we run them on different circuits within the RV and then also running the AC. But that does take some really careless action and does mean we are working outside the design.

I'm not all that concerned about the normal load of the RV causing the problem. If that were the case the RVs own main breaker would probably be tripping with some regularity. I'm more concerned about some sort of defect in the system. We're talking about vehicles that move and have a reputation for questionable wiring.

This is 12 volt wiring, but the wiring on my RV marker lights is backwards regarding the color of wires. That's pretty sloppy, but because they install incandescent bulbs it doesn't affect the operation of the lights. Was the 110 volt wiring installed by someone better?

[Goodspike]

Here's a possible solution to needing a 30 amp connection but only having a 50 amp outlet available. Buy something like this and wire a 50 amp male plug on the one side and a 30 amp outlet plug on the other side, using 30 amp barrel fuses.

https://www.amazon.com/Siemens-WF203...4281832&sr=8-1

Or you could put a 50 amp male plug on this and have some way to temporarily strap it to the pedestal.

https://www.amazon.com/TL137US-Tempo...s%2C225&sr=8-2

Either way I'd want to have a 50 amp tester that checked the proper wiring on the 50 amp outlet you were plugging into before plugging such a device in.

Note I have not seen either of these devices in person or read their documentation. They may not be suitable for some reason I am not considering or not aware of.

[Morich]

When there is the everyday item which thousands use versus working out a way to avoid using the normal thing, I do not recommend looking to online for any product to improvise.
The problem is not that it could not be made to work but that the person doing it likely will not fully understand how to do it safely. There is a risk of sorts with the dogbone option but it has proved much safer than suggesting most people improvise!

[Goodspike]

Originally Posted by Morich

When there is the everyday item which thousands use versus working out a way to avoid using the normal thing, I do not recommend looking to online for any product to improvise.
The problem is not that it could not be made to work but that the person doing it likely will not fully understand how to do it safely. There is a risk of sorts with the dogbone option but it has proved much safer than suggesting most people improvise!

I agree someone would need to have a knowledge of wiring, or simply be willing to pay an electrician to wire it up. I'm a little surprised this type of product doesn't exist.

I just have a problem using something that is inherently unsafe and a product that really should not be on the market. I don't care that it does work fine very often. The same could be said for putting a larger size fuse in an old style fuse box. That's done a lot with relatively few fires. That doesn't mean anyone should do that.

If the 30 amp didn't work I'd go down to the 15/20 amp connector. If that didn't work I'd go without power.

[Phil G.]

Originally Posted by Goodspike

I agree someone would need to have a knowledge of wiring, or simply be willing to pay an electrician to wire it up. I'm a little surprised this type of product doesn't exist.

I just have a problem using something that is inherently unsafe and a product that really should not be on the market. I don't care that it does work fine very often. The same could be said for putting a larger size fuse in an old style fuse box. That's done a lot with relatively few fires. That doesn't mean anyone should do that.

If the 30 amp didn't work I'd go down to the 15/20 amp connector. If that didn't work I'd go without power.

Hmmmm ... what do you consider unsafe about using an adapter like this in order to plug a 30A RV's power cord into the 50A receptacle on a campsite pedestal?:
https://www.amazon.com/gp/product/B0...language=en_US