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10David43's avatar
10David43
Explorer
Nov 13, 2019

Loss of 12v power when shore power is disconnected

I have a 2018 Shockwave 5th wheel, with a Go Power solar system. About one month ago, I had to replace my batteries because they did not seem to hold a charge, by morning the batteries would be almost dead from very moderate use of lights and water pump. I have never been able to run the heater at night, very moderately, without completely killing the batteries before morning. I choose to convert to 6v batteries wired in a series. It is at this point I noticed some electrical problems, though I had some electrical problems were addressed under warranty.

The first thing I noticed is my batteries would not charge to 100%, after being hooked up to shore power for a couple of days. I was checking at the Go Power control panel, while hooked up to shore power, when someone turned on a hair dryer. My battery levels began to drop quickly, indicating that my Go Power inverter was powering the hair dryer. After lots of research I found that, from the factory, my inverter had been set to run the 120v outlets all the time, probably why my batteries were shot so quickly. I turned the switch at the top of my inverter from “I” to “II”. The online Go Power manuel said it should be set to “II” when there is a remote control panel in the RV. That seemed resolved the issue of my inverter always powering some outlets.

Next issue I notice, my Go Power control panel says the batteries are sitting at 13.8v, but when I put a meter on the batteries they are now reading 18v. I am assuming I am having an issue with my converter and I also notice that my converter fan is not running when I plug in shore power. I was not able to deal with the issue for a few days and when I come back, the batteries seemed to have returned to normal voltage, so I did not think anything more about it.

Fast forward a month and we are going camping for the weekend. The 5th wheel has been hooked to shore power, the refrigerator is cold, and everything is fine, until I unplug from shore power. At that point all 12v items powered by my fuse panel go dead. I can still use my leveling jacks and start my generator. Starting my generator will re-power my 12v system. I do a complete search for a possible blown fuse. The circuit breaker going from the battery to the panel is good and there is power on both sides of the circuit break, but there is no power at the panel. I cannot see where the positive power wire goes after leaving the circuit breaker, there is no access to the wire from the circuit breaker to where it comes into the panel. I do not know if it goes to the inverter first. I pulled my converter and I can see that it does not go to the converter, so it is not running through the converter. Which should eliminate the converter from being the problem. I have checked my battery cut off switch and it is open and also providing 13.5v on both sides, prior to the circuit breaker.

I know this is a long question, but I have been pretty thorough with my diagnostics. My issue is I have no experience with inverters, this is my first RV with one. Any suggestions or ideas would be greatly appreciated.
  • David,

    Your scenario describes so many possible failures that nobody reading will be able to do more than maybe tell you where to start.

    The fact that you loose 12V system when not AC powered means that the house bank has a problem like a bad connection.
    The house battery bank should never be 18 volts.
    The most converter fans do not run full time, only as required.
    The fast voltage loss when loaded by the inverter says that the pair(?) of GC2s are not charged to full density.

    You changed out the house bank? Are you sure you got it all put back together correctly?

    If you can start the APU and run the jacks, then the house bank can't be that dead.

    Can you get a real schematic from Forest River? Do you have a buddy that is juice smart? Offer to buy him dinner if he brings his meter.

    Matt
  • 10David43 wrote:
    my Go Power control panel says the batteries are sitting at 13.8v, but when I put a meter on the batteries they are now reading 18v.
    It's hard to know where to begin, but, your batteries should *never* read 18v. Is is possible your converter thinks you have a 24v system? Is this during converter charging or do you have solar?
  • Yes it did. Can't say I love Forest River after buying this rig. For the price, there are a lot of poor quality parts.
  • Did this nightmare system come this way from the factory?

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