Forum Discussion

rwbradley's avatar
rwbradley
Explorer
May 06, 2014

Campsite Electrical

I am new to RVing, just graduated from tent camping to a 20ft Hybrid. I have been looking thru the forums learning as much as I can. I am curious about feedback on one area in particular. I have been reading about Surge Guards and the different things they can protect the TT from. There appears to be a lot of opinion about the value of having them vs their cost. I will likely invest the money in one, but in the short term, I would like to make sure I understand how to diagnose site wiring faults at the site. I have a decent multi meter in my toolkit.
I think I understand what to test and how, but want to confirm if my assumptions are right.
My TT is 30A, so if the ground (round prong) is up the hot wire would be left and neutral right. If I plug into a 15/20A service with a dog bone, pin out is the same. If I plug into a 50A service with a dog bone, if ground (round prong) is up, left and right are both hot and bottom is neutral.
- I should be able to see +105-125v from Hot to Neutral and Hot to Ground
- If I get a negative number testing hot and neutral, they are reversed
- If I do not get a reading hot to ground there is a ground fault
I assume if any of these are found, it could cause a serious electrical issue.
Are my assumptions correct or is there anything else I missed or worth knowing about verifying site electrical?
Thanks
  • Executive45's avatar
    Executive45
    Explorer III
    May 06, 2014
    Just a quick note on the surge protector. When you plug in you're going to check the pedestal and ensure everything is ok, AT THAT MOMENT! The surge guard monitors the pedestal at all times and will alert you if there are any changes, which can happen at any time........Dennis
  • hmknightnc's avatar
    hmknightnc
    Explorer
    May 06, 2014
    rwbradley wrote:
    Thanks for all the replies, I really wish I had taken Electricity in High School. One additional question that just came to mind.
    This time, when dealing with Amperage:
    - I am assuming that the circuit breakers are what protect me from drawing too much current
    - I also assume that the TT should than have a 30A master breaker that will protect me from trying to draw more than 30A (from all sources inside the trailer)
    - If I use a dog bone to connect to a 50A service, there should be no danger as the master breaker will protect me from drawing too much current
    - If I use a dog bone to connect to a 15/20A service, there is danger, as I could draw the full current and even try to draw more. In this scenario, there is no protection (from myself) and I could damage equipment, and a Surge Protector will do nothing to help.
    Again, are my assumptions correct?
    Thanks


    Your basically correct except for the dog one example. In that case the 15/20 amp breaker feeding the circuit is your protection. In other words you won't be able to pull the full 30 amps as the upstream breaker will trip
  • Allworth's avatar
    Allworth
    Explorer II
    May 06, 2014
    If you connect to a 15/20 Amp service and try to draw more than 15 (or 20) Amps, the house (or campground) panel breaker protecting the source circuit will trip. You CANNOT over-draw a breaker.
  • rwbradley's avatar
    rwbradley
    Explorer
    May 06, 2014
    Thanks for all the replies, I really wish I had taken Electricity in High School. One additional question that just came to mind.
    This time, when dealing with Amperage:
    - I am assuming that the circuit breakers are what protect me from drawing too much current
    - I also assume that the TT should than have a 30A master breaker that will protect me from trying to draw more than 30A (from all sources inside the trailer)
    - If I use a dog bone to connect to a 50A service, there should be no danger as the master breaker will protect me from drawing too much current
    - If I use a dog bone to connect to a 15/20A service, there is danger, as I could draw the full current and even try to draw more. In this scenario, there is no protection (from myself) and I could damage equipment, and a Surge Protector will do nothing to help.
    Again, are my assumptions correct?
    Thanks
  • RoyB's avatar
    RoyB
    Explorer II
    May 06, 2014
    Consider these three pictorials...

    Campground Pedestal wiring:



    Testing 50AMP circuit:


    Testing 30AMP CIRCUIT: Note - the 30A-20A-15A circuits are wired the same just different size wiring feeding the receptacles.


    Roy Ken
  • hmknightnc's avatar
    hmknightnc
    Explorer
    May 06, 2014
    It's AC Power, you are not going to get a negative number in any reading.

    30 Amp service: hot to neutral and ground should be 115 to 125. Neutral to ground should be zero volts

    50 Amp service: hot to hot is 230 to 250 volts and other checks same as 30 Amp service.
  • Gene_Ginny's avatar
    Gene_Ginny
    Explorer
    May 06, 2014
    rwbradley wrote:
    ...
    - If I get a negative number testing hot and neutral, they are reversed
    ...
    With AC you will never see a negative number on the meter.

    One more point, if you get ANY voltage reading from neutral to ground there is a reversal somewhere, most common is hot/neutral reversal.

About RV Newbies

4,026 PostsLatest Activity: Jun 15, 2017