XW6048 and generator problem

Cpfarr Registered Users Posts: 19 ✭✭
Hi guys

I just added a 30 kw genset to my off grid Xantrex 6048 system. When I fired up the gen it was dark out so the solar charge controllers are not supplying anything to the system right now. When e system fired up the 6048 was showing ac power from the genset. The control panel is showing 98 amps going to the batteries and -7600 watts on AC2. The system threw a F48 code. When the genset is shut down the fault auto clears and the battery bank is showing a positive charge. Any thoughts as to why Im throwing the F48?

The AC2 on the control panel is showing as 120V. The Xantrex manual sais the system does not support a 120V genset which is why I bought a 220 setup. The breaker in the power distribution panel is a 60 amp breaker wired for 220. Not sure if this has anything to do with the F48.

Thanks in advance, Chad


  • BB.
    BB. Super Moderators, Administrators Posts: 33,471 admin
    Re: XW6048 and generator problem

    From the XW manual I found online (PDF), F48 is:
    DC Under Voltage Automatic DC under-voltage

    shutdown occurs if DC
    voltage is below LBCO
    voltage level.
    See F47.

    And F47:

    DC Under Voltage Automatic DC under-voltage

    shutdown (immediate)
    occurs if DC voltage is
    below 16 VDC (24 V
    system) or 32 VDC (48 V
    system). The fault clears
    and the inverter restarts
    when DC voltage reaches
    +2 V (24 V system)
    and VLBCO
    +4 V (48 V

    Check for the correct battery
    voltage at the inverter’s DC
    input terminals. Check for an
    external DC load on the
    batteries. Check condition of
    batteries and recharge if

    Sure sounds strange--did you check the battery voltage at the inverter's DC input when generator was running vs faulted?

    Is Vlbco (low battery cutoff?) set correctly.

    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • Ken Marsh
    Ken Marsh Solar Expert Posts: 114 ✭✭✭✭
    Re: XW6048 and generator problem

    The F48 code is battery under voltage.
    This does not make a lot of sense.
    If you are charging the battery at 98 amps it certainly would not be under voltage.

    If I am reading the manual right, pg A-2 specifies either 120 or 240 input for A-2 depending on how you hook up.
    The voltage acceptance range is quite high however.
    Any chance a wire got hooked up one terminal off?
    How long does it take before it throws a code?
  • Ken Marsh
    Ken Marsh Solar Expert Posts: 114 ✭✭✭✭
    Re: XW6048 and generator problem

    Another thought Cp,
    Perhaps you have your AC-1 and AC-2 ports reversed and are motoring your generator.
  • SolaRevolution
    SolaRevolution Solar Expert Posts: 410 ✭✭
    Re: XW6048 and generator problem


    -Make sure "Gen Support" is not enabled (inverter menu)
    -check that the combined draw of the loads and the battery charger do not exceed the AC input settings.
    -Check your batteries and all AC and DC wiring connections.

    It sounds like you have +/- 2000 watts of load. If your loads fluctuate much (tools, pumps, motors...???) the "Gen Support" could suddenly pull a large current from the batteries. The F48 (DC undervoltage auto shutdown) is caused by the voltage falling on the inverter's DC input. The voltage would also crash if the batteries are too small, if the cables are undersized or if the battery terminal connections are not clean.

    If you have one or more bad cells, your batteries could be the cause of this too. For instance; you have a 48 volt system (24 cells) and one cell goes bad the others would still be receiving the charge at the absorb voltage setting. The XW system could show that the batteries are full but the moment they get a load on them the voltage crashes. Battery SOC monitors could be fooled by this too. Check batteries by taking hydrometer readings and/or voltage readings for each cell while under load.

    Check the generator output on the SCP by going into the Inverter menu then "Meters". Scroll down and it should show both AC2 lines seperately at +/- 120 volts. They should be fairly even. You could also have some issues if your loads are only, or mostly connected to one leg.

    If all of this checks out it's time to make the call. Tec support. :cry:

  • Joe_B
    Joe_B Solar Expert Posts: 318 ✭✭✭✭✭✭
    Re: XW6048 and generator problem

    The 120 volts on the SCP is normal. Mine does the same.

    The F48 thing is a pretty common fault. It has been discussed here in other threads. It is on the bug list for Schneider to fix if they decide to. The gen support mode is the usual culprit. If you have Gen support mode disabled, then try setting the LBCO higher.