Part 2 - Wiring Test Notes

Discussion in 'Wiring' started by Kerry L. Calkins, Aug 14, 2019.

Tags:
  1. Kerry L. Calkins

    Kerry L. Calkins New Member

    Messages:
    13
    Likes Received:
    1
    Joined:
    Aug 8, 2019
    Location:
    Severance, CO
    More information on problem - Part 2: Wiring Test Recap

    Objective: Get the camper wiring working so I can use shore or house power to trickle charge battery when connected.
    Restating The Problem: Any attempt to plug into shore (house) power trips house 20 amp GFI plug. Assumption based on what I have read is that I need to find the ground fault which may be a neutral/ground wire connection causing a positive neutral. Not sure this is right.

    BACKGROUND:
    House Power: 20 amp 110v via GFI outlet in garage (without any load on circuit; normally has refrigerator on this circuit but I disconnected for test).
    Electrical system condition: No load on 110v (interior camper plugs on two separate circuits are all I have (I only have a gas heater which only uses 12v fan) and on 12v side (interior and exterior camper lights and running/back up lights, and charging wire through harness to truck), and no battery connected.
    Grounds: I located four ground connections to the trailer frame. 1 main large bare copper wire (converter direct ground to frame through floor), 2 smaller gage white wires from within trailer connecting to trailer frame (shore power side front), and 1 from battery to frame (near battery). I unfastened all ground connections to the trailer frame. I cleaned all and connected.
    Continuity Test: I understand the there should be zero continuity when you test the disconnected 30 amp shore power plug between ground and either post. Is this correct? If not, what is the correct procedure to find the ground fault.

    Step By Step:
    1 - Testing the PUP 30 amp plug for continuity I get: Nothing between ground and hot wire post; but I do get continuity between ground and the neutral post. This occurs with the converter breakers on or off.

    2 - I trace the neutral wire back ...
    (a) from converter 10 gage neutral in and still get continuity on all downstream neutral wires, ground block, and branch ground legs;
    (b) with main neutral disconnected ... checking from main neutral feed into the converter ... I still get continuity everywhere downstream;
    (c) when I disconnect the main ground block on converter (copper wire running through floor and attaching to trailer frame), there is no continuity on neutral anywhere;
    (d) when I check continuity on cooper ground wire only I still get continuity. Does this mean the main ground wire is bad or does not have correct ground to trailer frame?
    Feed back is welcome. Trying to work my way to solving this problem.

    KC
    Colorado Spartan
     
  2. SteveP

    SteveP Well-Known Member

    Messages:
    1,446
    Likes Received:
    384
    Joined:
    May 21, 2015
    Did you test using the same connections and equipment prior to replacing the converter?
     
  3. Kerry L. Calkins

    Kerry L. Calkins New Member

    Messages:
    13
    Likes Received:
    1
    Joined:
    Aug 8, 2019
    Location:
    Severance, CO
    No. I changed the converter because the old one did not have the capacity to trickle charge the battery. It had old old pull button breakers ... the main was blown and replacement was hard to find. The cost to fix the old was nearly same as the new converter with modern switch breakers and multiple 12v fuses.

    I had never cleaned up the ground connections, because the 12v side worked.
     
  4. NMroamer

    NMroamer Active Member

    Messages:
    485
    Likes Received:
    235
    Joined:
    Apr 21, 2016
    Location:
    Albuquerque NM
    I don't have a lot of experience with travel trailer and popups. From a electrican view I would not want the AC ground and the DC negative connection to be the same.
    The AC should get it's ground from the shore power connection.
    I think the GFI is sensing the unbalanced connection.
    There are two different electric systems that should only be connected through the converter.
     
  5. SteveP

    SteveP Well-Known Member

    Messages:
    1,446
    Likes Received:
    384
    Joined:
    May 21, 2015
    My only thought is that you have a DC negative, white, and AC neutral, also white, cross connected. They should not share the same buss. The DC negative and AC ground are both connected to the frame, so if you have the DC and AC whites connected you've effectively run the AC neutral to ground.
     
  6. Kerry L. Calkins

    Kerry L. Calkins New Member

    Messages:
    13
    Likes Received:
    1
    Joined:
    Aug 8, 2019
    Location:
    Severance, CO
    Steve:

    That would be a distinct possibility if this camper had A/C. I follow your logic. I did find two small gage white wires coming from the trailer and grounded to the frame on front (I have yet to trace these to source).

    However, this is the no frills 1995 Starcraft PUP. It came with out appliances. No A/C, no refrigerator, no water heater, nada. I had RV dealer install a LP gas heater, which only uses 12v 30am fused circuit for power. So my only appliance is the heater (12v for the fan).

    This Starcraft economy model only had a 30 amp power converter (MagnaTek Series 6400A Model 6409) which fed shore power to two 110v outlets. In the old converter, each outlet was on a separate line with breaker (one 20 amp and one 15 amp). The converter had a switch between 110v and 12v. The 12v system was powered by wire from battery to 12v side of the converter and out to lights (and separate line to heater fan). The converter had no trickle charging ability. Battery charging was limited to the truick to trailer connection (which RV dealer added for me when I bought the PUP). The new Power Converter is a Parallax 6730D. I think will will do me well when I can resolve this problem.

    My motivation to upgrade the new converter was primarily to be able to trickle charge the battery when shore, generator, or house power was available. My secondary reason was to have modern breakers and 12v fuses in the camper. I bought the camper to avoid tenting on the ground. My son and I use it for hunting and fishing trips and we cook outside anyway, usually in remote camping with out shore power.For my remote camping I used a solar 15 watt collector and adapter (direct to battery with no connection to converter) to trickle charge during the day. That works great by the way.

    WM6
     
  7. McFlyfi

    McFlyfi Active Member

    Messages:
    397
    Likes Received:
    162
    Joined:
    Aug 1, 2014
    Location:
    Thousand Oaks CA
    Im pretty sure the "AC" Steve is referring to is "Alternating Current" (shore power) not "Air Conditioner". He is surmising that you've grounded your Alternating Current to the frame along with your Direct Current.
     
  8. tenttrailer

    tenttrailer Art & Joyce - Columbus, O

    Messages:
    3,126
    Likes Received:
    288
    Joined:
    Jul 18, 2013
    Location:
    Thornville, OH
    "(c) when I disconnect the main ground block on converter (copper wire running through floor and attaching to trailer frame), there is no continuity on neutral anywhere;
    (d) when I check continuity on cooper."

    Not sure I'm reading it right? The neutral is normally white. When you remove the copper wire from the buss in the breaker box to the frame. You should have continuty between all the neutral connections of the 120 all the way to the end of the shore power cord.


    It normal to ground the 120 to the frame and ground 12v DC to frame
     
  9. Kerry L. Calkins

    Kerry L. Calkins New Member

    Messages:
    13
    Likes Received:
    1
    Joined:
    Aug 8, 2019
    Location:
    Severance, CO
    Art - Thanks for the clarification. Understand both 110 and 12 v are both grounded to frame.
     
  10. Kerry L. Calkins

    Kerry L. Calkins New Member

    Messages:
    13
    Likes Received:
    1
    Joined:
    Aug 8, 2019
    Location:
    Severance, CO
    McFlyFi - Understood.
     

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.