Power cord

Discussion in 'General Camping Discussion Forum' started by Horby, Jul 8, 2018.

  1. Sjm9911

    Sjm9911 Well-Known Member

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    It's not the confidence of your wiring , it's the draw of the voltage through it, if you draw more amps then the cord is rated for you will get heat , and eventually failure, fires , etc. It's why there are ratings on these things to begin with.
     
  2. TeamECKO

    TeamECKO Member

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    I don’t have any high draw electronics (like an A/C) so I couldn’t imagine pulling 50 amps, or even a full 30 amps for that matter. So as long I ensure that I’m not pulling more than 30 amps while I’m hooked up to 50 amp, I should be OK? I have seen on some of the pedestals where there are two 25 amp breakers above the 50 amp plug. To be safe I suppose I could only close one of the 25 amp breakers if I am going to use the 50 amp plug.
     
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  3. Sjm9911

    Sjm9911 Well-Known Member

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    If you don't draw that much your ok! Lol. But I can easily see someone plug in an a.c. , microwave, frige, etc. It will work , untill it dosent! I rather not have someone read that's it's fine and learn that something bad happened later. If it works for you, then good. Just be mindful of the draw.
     
  4. Toedtoes

    Toedtoes Well-Known Member

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  5. Sjm9911

    Sjm9911 Well-Known Member

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    Lol, he contradicts himeself, he said it only taps one leg of the 220 service? But still can provide 50 amps? Hmmmm. Something is wrong with that statement. Yes , in theory they should trip, but I'm thinking dusty old breakers in a pop up might not be the most reliable. I still wouldent take the chance.
     
  6. Sjm9911

    Sjm9911 Well-Known Member

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    If it atually dropped off one leg, it would work. But then would only have half the power? 25 amps, as your using half of the original breaker.
     
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  7. joet

    joet Well-Known Member

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    The RV industry doesn't use 220 volt. Everything is on separate 120 volt legs.
    The last one I wired for a motor coach, I used 2-30 amp breakers GFCI. This way the pedestal could supply 30 amp at 120vt for small trailers as well as 50 amp for the larger units.
    And yes I would trust a dusty breaker to trip if overloaded
     
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  8. Toedtoes

    Toedtoes Well-Known Member

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    I believe that's because each leg of the 50amp outlet provides 110v 50 amps - for a combined total of 220v 50amp. If you only connect to one leg, you only get 110v 50amp. (I don't have a 50amp system, so have not researched it to a huge extent). - see post below as it makes more sense.

    As for chancing it, if you doubt the capability of your breakers, then you should update them. Even with a 30amp outlet, you need to be able to trust your breakers. Especially when you are plugging into unfamiliar pedestals.
     
    Last edited: Jul 9, 2018
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  9. Toedtoes

    Toedtoes Well-Known Member

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    OK, that makes more sense. In that case, your 30amp breaker would be sufficient to handle the load of 25amp.

    I do know the 50amp systems split the power inside the RV. And that the 50-30 dogbone adapter only connects half of the 50amp pedestal outlet.
     
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  10. Sjm9911

    Sjm9911 Well-Known Member

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    I'm atually a fire capt in a city, I see breakers go bad all the time. (New and old)! And I also see panels burn up from all sorts of surges. I would rather not have a larger wire then needed. As for the breakers, you never really can tell. I'm thinking the dog bone drops a leg, so you get half the power. If it was 50 amp on each leg it would be a 100 amp breaker. Yes, it's not 220, because they break it up in the ellectrical panel. So each side is feed from a diffent leg. Hope that wasn't too confusing.....
     
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  11. Sjm9911

    Sjm9911 Well-Known Member

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    Yes , if it drops a leg it's safe.!
     
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  12. Toedtoes

    Toedtoes Well-Known Member

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    That makes sense. And would be why it is safe to connect your 30amp camper to the 50amp outlet.

    i seem to recall seeing a diagram of the 50amp plug. It has four prongs rather than three. That fourth prong is the additional leg. When you connect the dogbone adapter, that fourth prong doesn't continue to the 30amp side.
     
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  13. SteveP

    SteveP Well-Known Member

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    The breakers in the pup will trip before you get that kind of overload. Assuming you have 1 15 and 1 20 amp breaker with no main breaker you are limited to 35 amps through the power panel. If you have a main breaker you are limited to the capacity of that breaker. There is a slight risk the shore power cord itself could short.
     
  14. joet

    joet Well-Known Member

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    The dogbone does drop a leg. That's why I prefer to use the 50amp receptacle's
    as they are the least used. After a while the prongs on the 30's will "wear out" from getting plugged into so much. Wear causes resistance, resistance causes heat along with increased amp draw.
    Remember...When in doubt it is better to call a professional, than trying to figure out what went wrong,,,, after the fire dept. has left.
     
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  15. TeamECKO

    TeamECKO Member

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    Pardon me, while I think out loud... I have a portable generator for our house and a wired in connection to our circuit box. When the electrician installed it he showed me how to connect the power cable between the house and the generator. He said I had to be sure to plug the cable in and rotate it to the right. If you only plug it in, you only received 110v, and only half of our breaker box would receive power. When you turn it to the right it received the full 220v, powering both sides of the breaker box. If my understanding was correct, if I plug into a 50 amp, and the pedestal did support 220v, I wouldn’t receive the full 220v since my 50/30 adapter doesn’t have the extra nun on the prong that engages when it is twisted to the right?

    I also have a 30 amp surge protector that I would hope would trip if I did pull more than 30 amps, tripping before it gets to the PUP?

    Thanks to everyone for your help and advice, and sorry Horby if I hijacked your thread.
     
  16. Sjm9911

    Sjm9911 Well-Known Member

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    I think I'm guilty of hijacking also. Sorry. Yes , dropping a leg means it's not the full 50 amps. The swivel connectors on your generator are probubly a hubble connector, that is just a locking system so the plug will not vibrate out. I dought it's for switching between 110 and 220, imagian the lawsuits! And thanks I learned something today.
     
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  17. Rusty2192

    Rusty2192 Active Member

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  18. Sjm9911

    Sjm9911 Well-Known Member

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    Ok so it's the full 50 amps, I wouldn't use it. You can, and will probubly never have a problum, me, I'm not taking that chance. Not worth it.
     
  19. Toedtoes

    Toedtoes Well-Known Member

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    ah sheesh... So then my first comment was partially true. The 50amp outlet provides two 120v 50amp legs. The dogbone drops one 50amp leg. You are then plugged into a single 120v 50amp outlet. Your RV breakers will break if you try to pull more than their limit which is less than the 50amps.
     
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  20. Toedtoes

    Toedtoes Well-Known Member

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    i think it really depends on what you're doing. I have never needed a full 30 amps, so I would never come close to overloading my system. Therefore, I would not have a problem with connecting to the 50amp outlet.

    For someone who is running near or at their 30amp limit, and may easily go over it, then it might not be worth the risk.
     

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