700 Watt Solar, Lifeline batteries 20′ ATC w/Onan


My customer has a 2017 ATC toy hauler with the 5500w Onan generator and wanted to add solar panels to their 20 foot trailer. It also had two 12 volt batteries. Silent renewable power was the goal, my promise of “it will just work” was the pot of gold at the end of the rainbow.

The Problems With Their Old System

The dual AGM batteries had a total capacity of 160AH but only 80AH useable without damaging them. This trailer was using the house battery to start the generator and was not reliable, leaving them to jump starting the generator.   After some years the batteries would no longer hold a charge making the electrical system dependent on being plugged in, not what this customer wanted. I love helping RVers unplug!

My Solution

I installed (the Beast-GPL-30HT) a 150 AH AGM Lifeline Deep Cycle battery for their house battery. This would let them use up to 120AH in a pinch. I then utilized another (32# but 550A @0 degrees F) Lifeline starting battery that is dedicated to starting the generator.

There seemed to be an issue with the stock Automatic Low Voltage Disconnect with which does not allow for a disconnect voltage ¬†less than 12.1v, which didn’t fit the 11v ability of the new house battery. I installed a Victron smart battery protect that is controlled and programed by smart device with a bluetooth application.

I also mounted two 350 watt, residential grade, solar panels on the roof, and connected it to a 100/50 MPPT solar charge controller made by Victron. Of course there are MidNite circuit breakers keeping everything safe as well.

The 150 AH AGM battery gives them enough capacity to run their TV and other eltronics all day and the furnace for an entire night’s sleep. The 700 watts of solar easily recharges the battery. Meanwhile, the Victron 100/50 MPPT provides a reliable control system to recharge the battery properly and completely. I also installed Victron’s cellphone app so that the customer can monitor everything.

If they get caught in several days of rain or parking in the shade. The house battery will shut off power before damage is done. The generator will start from the dedicated fully charged battery and charge the house battery from the converter.

If this type of install is what your after, let me know. Hire the BoonDoctor.

2 thoughts on “700 Watt Solar, Lifeline batteries 20′ ATC w/Onan”
  • Kevin says:

    Please contact me about a system like that but ours are on a 5th wheel in a park .

    August 22, 2020 at 1:33 pm
    • The BoonDoctor says:

      Please reach out to me by phone so I can get more information. 815-601-1142

      September 8, 2020 at 1:57 pm
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