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Topic: Can a 30 amp and a 20 amp be plugged into 50amp (Read 754 times) previous topic - next topic

Can a 30 amp and a 20 amp be plugged into 50amp

I used to know this stuff long ago.  And have made up boxes to do this.

Refresh my mind.  Can I plug a 30 and a 20 into a pedestal that goes to a box with a 50 amp female in it?  We used to make them up with a breaker on it if memory serves me.

Bob
"Riding and rejoicing"
Bob
1997 U320 40' Mid entry, build 5132,  wtbi ce27, 4th owner
2007 Solara convertible
2 prodeco tech outlaw ss electric bikes

1095 watts solar
08 Ls 460 and a sc430
2000 Ford F-250 superduty 4x4

Re: Can a 30 amp and a 20 amp be plugged into 50amp

Reply #1 –
Only if 20 amp outlet is NOT a GFCI, which is hard to find these days.

But one could combine two 30-amp outlets, because very few 30-amp outlets are GFCI protected.

But this would be more visible, using outlets at 2 different campground sites.

20-amp GFCI could be used if it is directly connected to a motorhome outlet.

Some have separated rear air conditioner from breaker box, so it can alternatively be used as normal, connected to breaker box, or used independently plugged directly into a campground 15 or 30 amp GFCI outlet. Works great on a very hot day when there is a 30-amp & 20-amp, or two 20-amp outlets, so both roof air conditioners can easily be used.

Re: Can a 30 amp and a 20 amp be plugged into 50amp

Reply #2 –
Just went thru this on another post; hope it helps ^.^d
FROM ANOTHER POST
So any expert electrical folks?

I have a 2 plugs - 30A or 1 30A and 20A wired into a 50A female. Looked at the wiring all looks like white to white, black to black, green to green.

I have 2 30A plugs at a campground on the pedestal.

Does this make 50A? Using the 2 hots, 2 neturals and ground :-\

I will be at this camp for 3 months thru summer so I need a solution. :headwall:
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progressive_industries_50_amp_cheater_box-17106-2.jpeg

From Michelle
No.  Not in the sense of a true 50 amp 2-phase hookup.  At best you would have 20 or 30 amps available on each hot, all dependent on the campground wiring.

RV Electric scroll down the left and select 30/20 pigtail for more explanation.
RV Electric
The selected media item is not currently available.
My advice and experiences are Free, you decide if they are worth anything .

John - driving Old Faithful
1994 U280 GV
C8.3, Banks, Pacbrake, 900 watts, Resonator, XLHD tow dolly
Retired Army Warrant Officer

Life is what you make of it - if it is lemons, make lemonade!
Former Coaches:
1988 GV 40' ORED 300HP CAT - 9 years
1990 Winnebago LeSharo - 3 years
2000 Newmar London Aire - 3 years (#18 of 23 produced)

Re: Can a 30 amp and a 20 amp be plugged into 50amp

Reply #3 –
50 amp campground outlet = 50 amps @ 220 volts = 100 amps at 110 volts

30 + 20 amp campground outlets = 50 amps @ 110 volts 30 + 30 amp campground outlets = 60 amps @ 110 volts

If making own 'cheater' box from two campground outlets combine campground wires from both outlets to motorhome female 50 amp socket: Green+green to green round socket

White+white to white centered flat socket Black to (red) one outer flat socket Black to (black) other outer flat socket

Don't expect it to work with GFCI campground outlets.

If making your own 'cheater', better to build it with #10 wires to two male 30 amp plugs. If combining campground 30 + 20, use a 30 to 20 adapter. If combining campground 20 + 20, use two 30 to 20 adapters. This is a handy 'cheater' and adapters to have.

If buying a 'cheater' look for ones with two male 30 amp plugs.
Cheater Box

Re: Can a 30 amp and a 20 amp be plugged into 50amp

Reply #4 –
Barry,

Is it a true 60? I dont think it is :(  I know it seems that way..

Less than 100 feet length
First 30A (10g)wire is much smaller than 50A(6ga) The link describes this.
Second 30x120v=3600x2 legs=7200 volts 50x120v=6000x2 legs=12000v

This is because our MH are wired with 2-50A legs one for each side. 30A wire does not have the capacity to carry the current.

Hope this helps, cause I too did the math and logic-now I understand that with electricity it dosent work that way. ^.^d
The selected media item is not currently available.
My advice and experiences are Free, you decide if they are worth anything .

John - driving Old Faithful
1994 U280 GV
C8.3, Banks, Pacbrake, 900 watts, Resonator, XLHD tow dolly
Retired Army Warrant Officer

Life is what you make of it - if it is lemons, make lemonade!
Former Coaches:
1988 GV 40' ORED 300HP CAT - 9 years
1990 Winnebago LeSharo - 3 years
2000 Newmar London Aire - 3 years (#18 of 23 produced)

Re: Can a 30 amp and a 20 amp be plugged into 50amp

Reply #5 –
Quote from: fouroureye –
Barry,

Is it a true 60? I dont think it is :(  I know it seems that way..

Less than 100 feet length
First 30A (10g)wire is much smaller than 50A(6ga) The link describes this.
Second 30x120v=3600x2 legs=7200 volts 50x120v=6000x2 legs=12000v

This is because our MH are wired with 2-50A legs one for each side. 30A wire does not have the capacity to carry the current.

Hope this helps, cause I too did the math and logic-now I understand that with electricity it dosent work that way. ^.^d

The adapter provides (at best) two 30 Amp, 120 Volt circuits. The standard RV "50 Amp" connector provides two 50 Amp, 120 Volt circuits. Actually, it is designed for one 50 Amp, 240 Volt circuit, where the two 120 Volt circuits are 180 degrees out of phase.

Note: The neutral wire in a "50 Amp" connector circuit is designed for a 240 Volt system with relatively balanced loads on each leg. It is *not* sized for the two legs to be 120 Volts in phase, which would require it to carry the 100 Amps return current from the two 50 Amp in-phase 120 Volt lines.
David and Carolyn Osborn
1995 U320C SE 40' Build 4726 Feb 1995
FMCA 147762
Motorcade 17186

Re: Can a 30 amp and a 20 amp be plugged into 50amp

Reply #6 –
David,

If you review the link from post #2 that is what the article explains.
The selected media item is not currently available.
My advice and experiences are Free, you decide if they are worth anything .

John - driving Old Faithful
1994 U280 GV
C8.3, Banks, Pacbrake, 900 watts, Resonator, XLHD tow dolly
Retired Army Warrant Officer

Life is what you make of it - if it is lemons, make lemonade!
Former Coaches:
1988 GV 40' ORED 300HP CAT - 9 years
1990 Winnebago LeSharo - 3 years
2000 Newmar London Aire - 3 years (#18 of 23 produced)

Re: Can a 30 amp and a 20 amp be plugged into 50amp

Reply #7 –
I have added a pair of 30 amp twist lock plugs in the utility bay and a 30 amp RV cord can be plugged into each one. I ran an extra neutral wire from the power panel to the utility bay and installed a selector switch on the power panel so that I can plug into two seperate 30 amp plugs with ground fault. Each 30 amp plug provides power to half of the breakers in the power panel, just like the red and black hots do in the 50 (really 100 amps) power cord.

Works great in Canada where most campgrounds do not have 50 amp service.
Wyatt
96 U320 40 WTFE, build 4943
84 Toyota Supra towd
2015 Jeep Wrangler towd
Victoria, BC, Canada

Re: Can a 30 amp and a 20 amp be plugged into 50amp

Reply #8 –
John & Cheryl,

Not sure what you mean by 'true' And in your examples, you mean=7200 WATTS & 12000 WATTS? (not volts) Math works even with electricity.

If you are talking about the double 30amp #10 plugs to one 50amp female socket, #10 wire size is correct as campground breaker will trip if drawing more than 30amps.

60amp max draw using the double 30amp cheater only needs #10 in cheater. 60amps is the sum of the 30amp parts.

Continue your questions, as you are on the right track. There is a simple answer for your electric question, just ask it differently.

Saying it another way, you are correct in that 50amp plugs need #6 wire size, but 30amp only needs #10 wire size. Using a cheater, the campground outlet has 30amp breakers.

Barry & Cindy
 

Re: Can a 30 amp and a 20 amp be plugged into 50amp

Reply #9 –
Barry,

Your correct my mistake - watts not volts. :facepalm:
The selected media item is not currently available.
My advice and experiences are Free, you decide if they are worth anything .

John - driving Old Faithful
1994 U280 GV
C8.3, Banks, Pacbrake, 900 watts, Resonator, XLHD tow dolly
Retired Army Warrant Officer

Life is what you make of it - if it is lemons, make lemonade!
Former Coaches:
1988 GV 40' ORED 300HP CAT - 9 years
1990 Winnebago LeSharo - 3 years
2000 Newmar London Aire - 3 years (#18 of 23 produced)