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mrad's avatar
mrad
Explorer II
May 27, 2021

Need Some help with my battery system

Last fall we purchased a used toy hauler with an onboard Onan 5500. It also has a residential fridge. We had the dealer install two golf cart batteries in place of the 12-volt batteries. The tech guy didn't tell us anything about the Xantrex pro display or its purpose.

Yesterday I wanted to get an idea of how long the batteries could power the fridge. At 9:00 am I unplugged from shore power. My Xantrex Pro digital display showed 12.8 volts. When I came back 5 hours later, the display was showing an E05 code. I plugged back into shore power. This morning before I left for work, I checked the display again and it was still showing the E05 code.

Does anyone know what that code means?
Shouldn't 6-month-old golf cart batteries be last longer than 5 hours when powering a residential fridge?

23 Replies

  • E05 Red Overload shutdown
    Short circuit
    Reduce or disconnect the load. Make sure the load does not
    exceed the XM 1800’s output rating.
    Check connection to the load.


    Are you certain the inverter only powers the fridge?

    I assume you may need to cycle the inverter power off/on to get the inverter to restart.
    What is the battery voltage?
  • jdc1's avatar
    jdc1
    Explorer II
    Minimum Power Needed for a Residential Fridge
    The minimum power for running solely the residential fridge for 24 hours is six AGM batteries totaling 600 amp hours (300 ah usable). PLUS you need 600 watts of solar power on the roof to replenish the batteries during the daylight hours.Mar 27, 2016

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