Phantom Drain: Solved!

Our problem: We had a constant 3amp or so current drain. We’d also turned the air conditioner on accidentally when we were running on batteries. Subsequently, we basically flatlined our batteries (below 10.5 volts) during the night.

The next several days we tried to bring the batteries back up, but, with the constant 3amp drain and the batteries being flatlined, it took a large amount of solar to bring them up. We tried to use the charger on our inverter, but that wouldn’t work until the batteries were charged up a little. We had to run our converter at night to keep our batteries topped off.

The solution: The solution was two-fold. The current drain came from our fifth-wheel breakaway switch. The activator plug had been loosened just enough so that it looked, to the casual glance, like it was in. It wasn't, however, so the electric trailer brakes were on all the time. We only discovered it was out when we hitched up to move the trailer down to a solar shop. Since the trailer brakes were on, the trailer refused to budge. Putting the activator plug in all the way turned off the brakes and fixed the current drain.

The solar shop tested the batteries and seemed to think they were OK, that no lasting damage had been done. We’re not sure about that diagnosis, so we’ll be keeping an eye on their capacity and charging/discharging ability. The other interesting thing they found was that the other solar installer (back in 2003) had wired the negative pole of the batteries to the battery side of the shunt AND ran a wire from one of the negative poles to chassis ground .The other side of the shunt also goes to chassis ground. Our Link 1000 wasn’t giving us accurate current figures.

Anyway, the SB2000 and the Link 1000 now are within 0.05 amps of each other. As I type this in, we're pulling in 18amps from our panels (3 Kyocera 120-watt, tilted towards the south) and our batteries are charging right up nicely. The volts are still a bit different, but the solar guy seemed to think that was normal. The readings are closer now, however. So we can now resume our usual solar lifestyle, where most of our power comes from the sun and all is right with the world.

Thanks to BB, crewzer, and niel for their suggestions, hints, and observations. I've certainly learned a bit.

Comments

  • BB.BB. Posts: 27,681Super Moderators admin
    Re: Phantom Drain: Solved!

    Congratulations! I love it when a plan comes together. 8-)

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • BrockBrock Posts: 629Solar Expert ✭✭✭
    Re: Phantom Drain: Solved!

    Yaaaaa, just make sure you get the batteries a good topping off to make sure they are fully charged at some point soon.
    3kw solar PV, 8 L16's, xw 5548, Honda eu2000i, iota DLS-54-13, Leaf EV, 4 ton horizontal geothermal, grid tied - Green Bay, WI
  • System2System2 Posts: 6,290 admin
    Re: Phantom Drain: Solved!
    silverjim wrote:
    We tried to use the charger on our inverter, but that wouldn't work until the batteries were charged up a little.

    Do I understand correctly - that you were trying to charge your batteries by running your battery charger with power from your inverter, which gets it's power from your batteries??

    If so, this WILL NOT WORK. Due to inefficiencies on both the inverter and the charger, as well as losses in the wiring etc, this will take probably twice the energy FROM the batteries, that the charger will put back in. Another version of the Perpetual Motion Machine. There is no such thing.
    Cheers
    Wayne
  • BB.BB. Posts: 27,681Super Moderators admin
    Re: Phantom Drain: Solved!

    I think he has one of those inverters that also have an integral charger too (like the Xantrex series with the AC pass-through/charger/UPS switchover like functions...

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • System2System2 Posts: 6,290 admin
    Re: Phantom Drain: Solved!

    BB has got it right. I have a Heart Freedom 2000-watt inverter with a built-in 100 amp charger. Perhaps my explanation could have been clearer.

    -silverjim-
  • crewzercrewzer Posts: 1,832Registered Users, Solar Expert ✭✭✭✭
    Re: Phantom Drain: Solved!

    Great news! :-)
  • System2System2 Posts: 6,290 admin
    Re: Phantom Drain: Solved!

    :-D Yes, Great news!
    Good luck.
    Wayne
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