30 Amp RV to a 50 Amp post - Surge protectors and such

[ZZSPIRAL1]

There seems to be a difference in opinion on whether it's "safe" to use a dog bone to connect 30 amp RV up to a 50 Amp post. What's your opinion?

Additionally, I would like to order a surge protector, and I'm leaning toward one that's 30 amps. In your opinion, is it safe to connect a 30 amp surge protector to a 50 amp post using a dog bone? Note: There's not a 50 amp RV in my future.

One more question, what do you use as a surge protector (if any) when your RV is connected to a receptacle at home? I guess these receptacles are 15 or 20 amps. Truth is, I don't know if mine are 15 or 20. It probably doesn't matter anyway, on the condition the equipment (e.g. the surge protector) is rated for more than 20 amps.


I'm amazed at the considerations that go into an electrical system. Thanks in advance for your input.......

[wa8yxm]

Assuming you have a 30 amp rig.

Is it safe to hook to a 50 amp outlet with a dogbone.. Might be safer than hooking to a worn out 30 amp in the same box

Is it safe to use a 30 amp surge guard... Same answer.

[RoyB]

Just got back on here .... Glad I came out ok as I was just copying what DMBRUSS.com listed. He is the author of the top drawing as well... I would have measured my 50A MALE to 30A FEMALE adapter but it isn't at this location... I feel it is correct as shown but wish I could have measured one to be sure...

It does make sense to me to only grab one of the HOT legs when coming down from 50A to 30A service. Shorting those two HOT LEGS together on the 50A side would surely cause a very LARGE SPARK haha... Thats 240VAC between those two HOTs...


Roy Ken

[teddyu]

The first diagram provides power from a 30A pedestal receptacle to a 50A female plug. Both L1 & L2 are power from the single 30A hot lead to provide full power to the 50A system. The second diagram would work for a 50A pedestal receptacle powering a 30A female plug. First is s 30A/50A adaptor, the second is a 50A/30A adaptor. JM2¢...

[RoyB]

Does anyone have a link for a schematic diagram of the 50A MALE to 30AMP FEMALE dogbone adapter. I have been searching the internet for the past hour trying to locate a drawing of it - no luck...

I would like to see where the HOT SIDES of the 50A MALE connector go to. Are they paralleled to both sides of the source HOT1 and HOT2 wires.

This is true for the 50A FEMALE to 30A MALE RV adapter as shown in this diagram..

Anyone have any info on this. My 50A MALE to 30A FEMALE adapter is not here for me to measure...

This is a diagram showing the wiring diagram of a RV30A MALE to RV50A FEMALE. Note the strap on the 50A side connecting the two HOTs together.


NOTE - Disregard I just found what I was looking for... DMRUSS.COM has it shown


Roy Ken

[ZZSPIRAL1]

I ended up with the Progressive Industries PT30C 30 Amp Portable.

I didn't want to deal with the potential of somone doing poor work and I don't know electrical systems enough to install a hard-wired device. I'm a DYI guy, but have my limits.

But I'm happy with the purchase. I really like the bracket on the cord, so I can lock this up. Plues I bought some adapters, so I can use the Progressive when I'm hooked up to my 15 amp at home or abroad.

Thanks for all the good information.

[LarryJM]

ZZSPIRAL1 wrote:
There seems to be a difference in opinion on whether it's "safe" to use a dog bone to connect 30 amp RV up to a 50 Amp post. What's your opinion?

Not sure how you came to that conclusion since I haven't noticed it with the only potential issue being the lower rating of the dogbone, power cord and wiring internally up to the 30A main in the trailer. Issues there are possible, but I have yet to see a post or instance of it in relation to being hooked up to a 50A service.

Additionally, I would like to order a surge protector, and I'm leaning toward one that's 30 amps. In your opinion, is it safe to connect a 30 amp surge protector to a 50 amp post using a dog bone? Note: There's not a 50 amp RV in my future.


Absolutely and the surge protector doesn't have or perform the functions of a normal circuit breaker and I'm not even sure how you would wire a 50A unit into a 30A circuit except if the surge protector was portable and then you would have to have a 30A to 50A adapter should you be hooked up to a 30A only pedestal.

One more question, what do you use as a surge protector (if any) when your RV is connected to a receptacle at home? I guess these receptacles are 15 or 20 amps. Truth is, I don't know if mine are 15 or 20. It probably doesn't matter anyway, on the condition the equipment (e.g. the surge protector) is rated for more than 20 amps.


Mine is hard wired and performs the same functions when I'm connected to my 20A service at home as when I'm connected either to a 30A or 50A pedestal at a campground. It is protecting against power surges, high/low voltages, and miswired or incorrect power sources.


I'm amazed at the considerations that go into an electrical system. Thanks in advance for your input.......

There is actually very little to consider in selecting a surge protector with the two being "hard-wired" or "portable" and for the most part either a Progressive or SurgeGuard unit. Functionally all do basically the same thing as long as you get one that has the voltage monitoring capability and not purely just "SURGE" protection.

Larry

[time2roll]

ZZSPIRAL1 wrote:
Hey smkettner, just saw your reponse. Here are some pictures. I don't know what these will tell you, but I don't see a J-box.

I've never posted pictures before (hope this works). Pictures in order: 1. Cable coming from receptacle. 2. Cable going into floor. 3. Just a demonstration of what's under that fidge. 4. Behind converter.

Note, there's a lot of room behind that converter. The oven is above it, though I "wouldn't" necessarily think that's a problem. As always..........thanks.

Well that failed. By chance do you have a Facebook? If so, then you should be able to see the pictures here. Note: the pictures are out of order now, but you get the idea:

https://www.facebook.com/rollin.graham.1#!/rollin.graham.1/photos

Sorry no FB. OK on my trailer the cord comes in the mouse hole and connects to romex at a J-box just inside the wall in the compartment where the cord gets all bunched up when I shove it in. Maybe you have a detachable cord or something else.

If you have space behind the electric panel that is fine also. Just remove the main romex/cord from the panel and connect to the EMS. Get a same rated piece of romex and connect from EMS to the same place in the panel where the wire was removed. This allows you to return it to oem configuration if you ever want to.

[time2roll]

+1 rbturner

Couple times all was good. Then in the middle of the movie power goes off and we have 135 volts :e

Put the inverter on and find our place in the movie and continue with the evening. By morning all was fine.

[rbturner]

I think that something to always keep in mind is; even though a guy checks the electrical system out with a meter or test light of some sort before you plug in, something can happen later. This all dawned on me when I experienced some goofy voltages last summer. Before I hooked up, the 50 amp outlet was fine. Later, my little single circuit voltage monitor went off; indicating an open ground. That issue resloved itself but that should have been a warning to me and I continued on. Later, the little monitor went off again for high voltage. I moved the monitor to another circuit and it had low voltage. What had happened was that the neutral/ground bond was lost at the recepticle; causing crazy voltage on each leg. The installer of the outlet had not run a separate ground wire but had run a jumper from the neutral lug to the ground lug of the outlet.

The moral of this story is that a "surge guard" or EMS will keep watching the electric side of life after you have plugged in. There is no gaurantee that even though you checked the electric system when you hooked up that it will continue to be proper.

[mlts22]

I recently stopped at a CG where the 30A receptacle had a very shaky connection. A quick clean with De-Ox-It, and not much better luck. So, I went to Wally World and bought a dogbone to use with the 50A connector. Worked perfectly.

[wa8yxm]

Since you said "What is your opinion" Mine is that it is safe.

However, if you wish to pick nits.

The "Danger" is that you have a cord rated at 30 amps, but it's protected by a breaker rated at 50.. Now, in theory it is possible to create a "Short" that will draw say 40-45 amps, not quite just enough to pop the circuit breaker but enough to seriously overheat the wires in the cord.

In practice, outside of a lab, dang near impossible to create such a short.

IF there is a short INSIDE the RV, then the 30 amp main breaker in your distribution panel will trip, thus protecting the cord. (not to mention many other things) or the lower current affected branch breaker will trip.

Now,,,, Why do it?

Well, epically if you use an RV Surge Guard/Power line protection device.

The lower voltage drop in the 50 amp wires "Up-stream" of the surge guard may cause it to hang in there in some few parks. Where as on a 30 amp site, when the air conditioner cuts in, the power guardian may shut you off it it's a bit too fast to respond.

[ZZSPIRAL1]

Hey smkettner, just saw your reponse. Here are some pictures. I don't know what these will tell you, but I don't see a J-box.

I've never posted pictures before (hope this works). Pictures in order: 1. Cable coming from receptacle. 2. Cable going into floor. 3. Just a demonstration of what's under that fidge. 4. Behind converter.

Note, there's a lot of room behind that converter. The oven is above it, though I "wouldn't" necessarily think that's a problem. As always..........thanks.

Well that failed. By chance do you have a Facebook? If so, then you should be able to see the pictures here. Note: the pictures are out of order now, but you get the idea:

https://www.facebook.com/rollin.graham.1#!/rollin.graham.1/photos

[time2roll]

Height might be similar but the EMS is wider and longer than a typical J-Box.

Post some pics of the proposed spots. You will need some room to work.
Hard to know with hundreds of posibilities.

[ZZSPIRAL1]

smkettner wrote:
With good access 30 minutes tops. The remote blinks with the different data about every second so best to have it kinda out of view. My preference anyway.

Panel to me is the breaker panel and yes most now also have an integrated converter to supply 12 volts.

Seems to me when you say replace the J box, room-wise, that "should" be a wash, or close to.