20 amp inlet to supplement 30 amp hookup

[powercat_ras]

There's so much confusion about electricity and RVs ...
There have been some posts in this thread that don't understand 50 Amp RV Outlets ...

15 or 20 or 30 Amp RV Outlet is the amps you can get at 120 VAC

50 Amp RV Outlet is 50 Amps at 240 VAC, and a full size Neutral wire is required.
This allows up to 50 Amps to be drawn at 120 VAC from each side of the 50 Amp Outlet.
So, a 50 Amp RV outlet is really a 100 Amp 120 VAC capability ( 50 Amp x 2 @ 120 VAC ).

A 50 Amp RV outlet can deliver over 3 times more power than a 30 Amp RV Outlet.

Hope this helps.

[jaearhart]

Yep, you are correct. Amperage determines wire size requirements. I'm a old wise retired licensed Journeyman Electrician with not so wise writing and posting on internet blogs. Like my wiring projects I should remember to Double Check before throwing that Breaker. Or another city inspector will tap ya on the shoulder. Enjoy your camping trip. I'm done posting .

[richard5933]

I can't say that this is true for all pedestals out there, but this is how ours is wired...

There is a two-pole 50-amp breaker at the main load center in the house. It feeds the pedestal with two hot conductors, a neutral conductor, and a ground conductor.

At the pedestal there is a two-pole 50-amp breaker, a single pole 30-amp breaker, and a single pole 20-amp breaker.

The two-pole 50-amp breaker is fed by both hot leads coming from the house. The 30-amp and 20-amp breakers each are fed by one of the two hot leads, sharing them with the 50-amp breaker. The pedestal is not designed to have a load on the 30-amp or 20-amp while the 50-amp receptacle is in use.

If I were to plug in and use the full available power on the 50-amp receptacle, and then plug into the 30-amp and/or the 20-amp receptacles, I would overload the circuit and the breaker in the load center back at the house would trip. That breaker is designed to allow a max of 50 amps to each leg, and since the 30-amp and 20-amp share the same hot leads as the 50-amp, they would be over drawing current.

However, if I don't use the 50-amp receptacle I can make full use of both the 30-amp and 20-amp receptacles with no problem. They are each drawing from a separate leg, and each of those legs are protected with 50-amp breakers back in the house on the main load center. They are protected at the pedestal with 30-amp and 20-amp breakers and can each be used fully as long as the 50-amp receptacle is off.

So, if the pedestal in the campground is wired like this it would probably be okay. The problem comes in not knowing exactly how the pedestal is wired. Likely it is okay to use both the 30-amp and 20-amp receptacles at the same time IF there is also a 50-amp receptacle at the pedestal.

However, if there is only a single 30-amp and a single 20-amp receptacle, I would assume that they both share the same leg from the main load center, likely fed with only a 30-amp breaker. In this case using both would trip the breaker at the main load center.

[jaearhart]

U rite, the NEC wiring code used for sizing cables is in AMPS. I make too many mistakes writing post so I'll just git off here . Happy camping.

[cavie]

Originally Posted by US1

My understanding is that as long as you have at least 2 outlets (a duplex counts as 2), that the 15A outlets are acceptable on a 20A circuit, being that the 15A outlet is good as a 'pass thru'. Whereas if you had just a single 15A outlet only on a circuit, it had to be a 15A circuit. Is this correct?

The red comment was directed at the 50 amp outlets.

[hencye]

This is what I have connected to my tool trailer to pass electric through. It is only 15 amp but works fine for everything I do, https://smile.amazon.com/gp/product/...?ie=UTF8&psc=1

This is the 20 amp version, it has one blade sideways, see pics and must be used with a 20 amp extension cord, https://smile.amazon.com/Leviton-153...1034038&sr=8-3

Either way, you should use a 12 gauge extension cord, that's all I use for every thing I do and I'm a general contractor.

As for the electrical panel, this is a little in depth, but might help you better understand it and possibly someone else who reads it. One poster said that the boxes at RV parks, as I believe you described it correctly, would be against code. I can tell you emphatically that they are safe and up to all electric codes as per the national electric code. If some local municipality has a different code, they they'd have to use a different box. I'm an electrician and an electrical engineer so not willing to argue about this!

The RV box has no main shut off in the box itself, the shut off is in the box that feeds this box. This RV box is considered a subpanel and can operate legally when connected to a main panel with a way to disconnect all power to the RV box, think your a/c disconnect outside your stick home, it only controls power going out of it, not into it. Same principle and code. Of course the main panel needs to also be done correctly, 2-50 amp breakers providing 110v each to the subpanel, all the way back to the electric meter which all must have the correct wire size even feeding the meter. All of this affects what you can do in your rig and I've run into issues because some older parks don't have what is needed upstream to give me what I need at my RV.

As long as the box has a double 50 amp breaker, then it is a 100 amp panel with 2 feeds, phases, whatever you want to call it, it's 2 separate 110 volt, 50 amp feeds, thus these panels are 100 amp panels. Each 50 amp breaker is 50 total amps out. One leg of the the panel feeds each of the 50 amp breakers. If the panel is wired correctly, then the 30 amp breaker, which is just 110, comes off of one of the panel leg/feed and the 20 amp comes off of the other leg/feed.

For what your describing with the 30 amp rig hookup and the 20 amp extension cord, again assuming everything is kosher at the panel and upstream, you'll trip all the breakers in your camper and at the pedestal before you pull more power then what is available at the pole as you'd be pulling 30 amps off of one 50 amp feed and 20 amps off the other 50 amp feed.

If someone is running a 50 amp rig and trying to do the same thing they will more than likely not trip any of the breakers inside their rig or in the RV pedestal box, but if they draw too much amps they could trip the 50 amp breakers in the main panel that feeds the RV box upstream.

Hope this makes sense and helps! Good luck and remember always check for power when doing things, don't assume someone else did and/or there's no power because you think the breaker is off! Private message me if you have any other questions as I won't monitor this.

[picker]

Over the years, on two motorhomes and a travel trailer, I have installed one of these.......used ONLY for a portable, 1500 watt space heater.

Allows use of microwave, momma's hair dryer, etc, without blowing the post.

https://www.amazon.com/dp/B009ANV81S...v_ov_lig_dp_it

I connect with this:

https://www.amazon.com/Woods-982452-...HCSBEJ1BBD0MWE

[garywilson]

Originally Posted by theoldwizard

HIGHLY UNLIKELY !

As a general safety statement, each outlet in a power pedestal must be protected by a breaker of no larger that what the outlet is rated for.

If the pedestal has say 3 outlets, 50A, 30A and a duplex 20A, It is likely that the 50A breaker is acting as the "main", feeding the 50A outlet and the 30A breaker (which feeds the 30A outlet) and the 20A breaker (which feed the 20A outlet). The total power for the pedestal is 50A @ 240V. The 30A outlet and the 20A outlets only use 1/2 of the 240V "split phase" feed. Hopefully, each uses a different half.

This might have been what you were trying to say, but it was not clear.


Be careful using a 20A plug on your extension cord ! NEC allows a 20A on a standard 15A (NEMA 5-15) outlet (assuming it is wired for 20A and protected by a 20A breaker), but if you have a NEMA 5-20 plug it will only plug into a 5-20 receptacle.

If this were true, you would not be able to use the 30 without the 50 turned on.
Each breaker protects the wire for that circuit.
Breakers are intended to protect the wire behind it, not whatever you might plug into it. Your 20 amp breaker could care less if your 15 amp appliance burned up.

[twinboat]

Originally Posted by hencye

The RV box has no main shut off in the box itself, the shut off is in the box that feeds this box.

This RV box is considered a subpanel and can operate legally when connected to a main panel with a way to disconnect all power to the RV box, think your a/c disconnect outside your stick home, it only controls power going out of it, not into it. Same principle and code.

Of course the main panel needs to also be done correctly, 2-50 amp breakers providing 110v each to the subpanel, all the way back to the electric meter which all must have the correct wire size even feeding the meter.

As long as the box has a double 50 amp breaker, then it is a 100 amp panel with 2 feeds, phases, whatever you want to call it, it's 2 separate 110 volt, 50 amp feeds, thus these panels are 100 amp panels.



Each 50 amp breaker is 50 total amps out. One leg of the the panel feeds each of the 50 amp breakers. If the panel is wired correctly, then the 30 amp breaker, which is just 110, comes off of one of the panel leg/feed and the 20 amp comes off of the other leg/feed.

For what your describing with the 30 amp rig hookup and the 20 amp extension cord, again assuming everything is kosher at the panel and upstream, you'll trip all the breakers in your camper and at the pedestal before you pull more power then what is available at the pole as you'd be pulling 30 amps off of one 50 amp feed and 20 amps off the other 50 amp feed.

If someone is running a 50 amp rig and trying to do the same thing they will more than likely not trip any of the breakers inside their rig or in the RV pedestal box, but if they draw too much amps they could trip the 50 amp breakers in the main panel that feeds the RV box upstream.

.

Most of what you said is wrong and the rest makes no sense.

You said ;

" As long as the box has a double 50 amp breaker, then it is a 100 amp panel with 2 feeds, phases, whatever you want to call it, it's 2 separate 110 volt, 50 amp feeds, thus these panels are 100 amp panels. "

Actually, if it only has a double 50 amp breaker, its a 50 amp 240 volt panel.

[cavie]

Originally Posted by hencye

This is what I have connected to my tool trailer to pass electric through. It is only 15 amp but works fine for everything I do, https://smile.amazon.com/gp/product/...?ie=UTF8&psc=1

This is the 20 amp version, it has one blade sideways, see pics and must be used with a 20 amp extension cord, https://smile.amazon.com/Leviton-153...1034038&sr=8-3

Either way, you should use a 12 gauge extension cord, that's all I use for every thing I do and I'm a general contractor.

As for the electrical panel, this is a little in depth, but might help you better understand it and possibly someone else who reads it. One poster said that the boxes at RV parks, as I believe you described it correctly, would be against code. I can tell you emphatically that they are safe and up to all electric codes as per the national electric code. If some local municipality has a different code, they they'd have to use a different box. I'm an electrician and an electrical engineer so not willing to argue about this!

The RV box has no main shut off in the box itself, the shut off is in the box that feeds this box. This RV box is considered a subpanel and can operate legally when connected to a main panel with a way to disconnect all power to the RV box, think your a/c disconnect outside your stick home, it only controls power going out of it, not into it. Same principle and code. Of course the main panel needs to also be done correctly, 2-50 amp breakers providing 110v each to the subpanel, all the way back to the electric meter which all must have the correct wire size even feeding the meter. All of this affects what you can do in your rig and I've run into issues because some older parks don't have what is needed upstream to give me what I need at my RV.

As long as the box has a double 50 amp breaker, then it is a 100 amp panel with 2 feeds, phases, whatever you want to call it, it's 2 separate 110 volt, 50 amp feeds, thus these panels are 100 amp panels. Each 50 amp breaker is 50 total amps out. One leg of the the panel feeds each of the 50 amp breakers. If the panel is wired correctly, then the 30 amp breaker, which is just 110, comes off of one of the panel leg/feed and the 20 amp comes off of the other leg/feed.

For what your describing with the 30 amp rig hookup and the 20 amp extension cord, again assuming everything is kosher at the panel and upstream, you'll trip all the breakers in your camper and at the pedestal before you pull more power then what is available at the pole as you'd be pulling 30 amps off of one 50 amp feed and 20 amps off the other 50 amp feed.

If someone is running a 50 amp rig and trying to do the same thing they will more than likely not trip any of the breakers inside their rig or in the RV pedestal box, but if they draw too much amps they could trip the 50 amp breakers in the main panel that feeds the RV box upstream.

Hope this makes sense and helps! Good luck and remember always check for power when doing things, don't assume someone else did and/or there's no power because you think the breaker is off! Private message me if you have any other questions as I won't monitor this.

Not SO! to be a 100 amp panel it must be labeled so and it must be feed by a 2 pole 100 amp breaker.

A ped wired per code will have the main breaker remote from the camp site. If it has a 50/30/20 set up then there will be a 50, a 30, and a 20 amp breaker. Each one fed from the sub-panel buss bar and not from the 50 amp breaker. The 50 amp breaker will feed the 50 amp receptical. The 30 amp breaker will feed the 30 amp receptical and the 20 amp breaker will feed the 20 amp receptical.

The 50 amp breaker will feed the 50 amp receptical only. not the 30 or 20 outlets.

[cavie]

Originally Posted by powercat_ras

There's so much confusion about electricity and RVs ...
There have been some posts in this thread that don't understand 50 Amp RV Outlets ...

15 or 20 or 30 Amp RV Outlet is the amps you can get at 120 VAC

50 Amp RV Outlet is 50 Amps at 240 VAC, and a full size Neutral wire is required.
This allows up to 50 Amps to be drawn at 120 VAC from each side of the 50 Amp Outlet.
So, a 50 Amp RV outlet is really a 100 Amp 120 VAC capability ( 50 Amp x 2 @ 120 VAC ).

A 50 Amp RV outlet can deliver over 3 times more power than a 30 Amp RV Outlet.

Hope this helps.

It's very obvious YOU do not understand 50 amp outlets.

NOT at all correct. 50 is 50. 100 is 100. Stop making up you own rules and code.

[cavie]

If anyone wants to give out electric advice around here you better know what you are talking about. There are quite a few professional electricians around here. And some very qualified non professionals also. They will go out of their way to stop bad information.

[richard5933]

Originally Posted by cavie

Not SO! to be a 100 amp panel it must be labeled so and it must be feed by a 2 pole 100 amp breaker.

A ped wired per code will have the main breaker remote from the camp site. If it has a 50/30/20 set up then there will be a 50, a 30, and a 20 amp breaker. Each one fed from the sub-panel buss bar and not from the 50 amp breaker. The 50 amp breaker will feed the 50 amp receptical. The 30 amp breaker will feed the 30 amp receptical and the 20 amp breaker will feed the 20 amp receptical.

The 50 amp breaker will feed the 50 amp receptical only. not the 30 or 20 outlets.

That goes along with how my pedestal is configured. Four 6 ga conductors enter the ped, feed the bus bars, and then feed the three receptacles through their respective breakers on the pedestal.

But, back in the breaker panel in the house the two hot leads (L1 & L2) to the pedestal are fed by a double-pole 50-amp breaker. My understanding is that this means that each side of the 50-amp receptacle in the ped are fed by the two incoming hot bus bars (L1 & L2), and the 30-amp receptacle shares one hot bus bar (L1) and the 20-amp receptacle shares the other (L2).

So, if someone where to make use of the 50-amp receptacle and then also plug in a 30-amp load on the 30-amp receptacle, the breaker back at the house panel should trip.

I think that where some get confused is in seeing the three breakers in the ped and assuming that means they can use all three receptacles (or two in the case of a 30-amp ped) to their limit. Since they are all fed back at the house panel with one double-pole 50-amp breaker, using all the receptacles would trip the breaker.

I'm not an electrician, so if I've got this wrong please say so.

[hohenwald48]

NEC discussions regarding RV park pedestal wiring always make me smile. And I can't count the number of times a "licensed master electrician" has blown an RV by wiring a 30 RV amp outlet with 240 volts so having that moniker doesn't necessarily get things wired properly.

In my work camping years I saw 50A outlets wired with 12 gauge wire, grounds used as neutrals, 50 amp hots jumpered from the same phase, 10 sites chained together using 8 gauge wire and more things that would ruin and inspectors day than I can recount.

A lot of RV parks are so poorly wired it's a miracle they work at all. It's always been my position that if you need to go to an internet forum to learn how to wire something you should probably not wire anything.

In response to the OP's post #1, yes you can do what you describe and will have no problems in most situations. There are plenty of miswired pedestals out there and you may run into issues if you happen to get one of those sites.