Conext XW+6848 during Grid Support mode waste 480watts doing nothing???

jimmyaz
jimmyaz Registered Users Posts: 114 ✭✭
edited May 2017 in Advanced Solar Electric Technical Forum #1
Hey guys,

I have recently installed a Schneider Conext XW+6848 intended to use for Solar PV self consumption meaning I want to use it in Hybrid mode (Grid Support mode).  If I recalled correctly the manual said in Grid Support mode, the inverter would always pull the first 2amps from the grid to ensure that it would not back feed the grid if you have Sell = Disable.  I am not using Schneider charge controller, but a Midnite Classic 150.   So I am not running Enhance Grid Support, just by voltage.

So my setting.

Grid Support: Enable
Grid Support Voltage: 52Volts
Sell: Disable

However, upon my finding.  I have SHUT the load output Breaker of the inverter off.  I have verify it with my clamp meter, load is pulling 0 both L1,L2.  But the Inverter is still pulling from the Grid L1 = 2.05A and L 2 = 2.06amps.  It's also pulling .8A @53Volt DC out of my battery bank.

What in the hell?  This thing is wasting 480watts AC and another 48Watts DC, just for being ON and in Grid Support mode.

So if I leave everything the same, Turn OFF Grid Support mode, then Grid L1, L2 show .8Amps  @240 = 192watts.

YES, both combox (Ver03.03BN0830) and XW+6848 (V02.03.00-0008) has firmware is up to date.

What could I possible done wrong?  Or this is just how this thing work?






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  • jimmyaz
    jimmyaz Registered Users Posts: 114 ✭✭
    #2
    Attached a log of my test.  I am not even sure why this is possible or how can it be acceptable this thing can waste so much?  I must be doing something wrong?

    All of these values are NOT from the Combox (as I know how those number are super inaccurate and basically useless.  All these number are from clamps meters. 






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  • Estragon
    Estragon Registered Users Posts: 4,496 ✭✭✭✭✭
    #3
    It seems to me that a clamp amp meter may also give inaccurate readings.

    That said, for the inverter to be using 30-50 watts just being on isn't surprising, and my understanding of this inverter is it will draw the first 'x' amps from grid. Do you know what 'x' is set to?
    Off-grid.  
    Main daytime system ~4kw panels into 2xMNClassic150 370ah 48v bank 2xOutback 3548 inverter 120v + 240v autotransformer
    Night system ~1kw panels into 1xMNClassic150 700ah 12v bank morningstar 300w inverter
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  • WaterWheel
    WaterWheel Registered Users Posts: 387 ✭✭✭
    #4
    I'll check some things when I get home.... but with my Grid support set at 50.0v instead of your 52.0v on loads less than about 10 amps I only pull about 90 watts from the grid.        On larger loads the grid covers most of the load.      Try turning down your grid support voltage to 50.0v and see if that helps.

    Conext XW6848 with PDP, SCP, 80/600 controller, 60/150 controller and Conext battery monitor

    21 SW280 panels on Schletter ground mount

    48v Rolls 6CS 27P

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  • jimmyaz
    jimmyaz Registered Users Posts: 114 ✭✭
    #5
    Estragon said:
    It seems to me that a clamp amp meter may also give inaccurate readings.

    That said, for the inverter to be using 30-50 watts just being on isn't surprising, and my understanding of this inverter is it will draw the first 'x' amps from grid. Do you know what 'x' is set to?
    The Inverter tare loss is not what we are talking about here, that I understand.  What I am saying is, why is my meter showing 2.05amps on both L1 and L2 Grid Input when there's NO load at all on the inverter.  The supposely first amps draw during grid support mode is NOT settable.  Manual said it can use up to 2-3kw minimum from grid when grid support is Enable.  So it should be like 130-150watts.
    WaterWheel said:
    I'll check some things when I get home.... but with my Grid support set at 50.0v instead of your 52.0v on loads less than about 10 amps I only pull about 90 watts from the grid.        On larger loads the grid covers most of the load.      Try turning down your grid support voltage to 50.0v and see if that helps.
    The grid support voltage doesn't really come to play here.  My question is why is it showing a Grid Intake of 2amps on both line when there's no load.  Schneider tech support said it should only be 1amps when there's no load.  Apparently that not correct either.  A fellow on youtube told me this.

    "Well, it appears that in grid support one phase actually feeds power in reverse direction, but your clamp cant pick it up. It shoud be 100-150 watts and 300-350 watts at full inverter capacity 6800 watts"

    If I understand that correctly, in grid support mode and there's no load.  The inverter loop the power around so it can detect the grid at all time.  Meaning it take power from one line and feed it back through... This is why I see 2.05A on L1 and 2.06A on L2.  However, since this is a AC and it flow both direction, my clamp wouldn't be able to tell which direction it's flowing.  But Schneider tech guy either doesn't know about this or didn't explain it like that to me.  But that's probably how it work, reading back on my log, if I take Grid input L1 subtract it with L2 and subtract out the load... then it does make sense.




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  • jonr
    jonr Solar Expert Posts: 1,386 ✭✭✭✭
    edited May 2017 #6
    When dealing with AC,  amps says nothing reliable about watts - it could be a reactive load just pumping current in and out, costing you nothing.

    I am available for custom hardware/firmware development

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  • new2PV
    new2PV Solar Expert Posts: 305 ✭✭
    #7
    If you have enough solar power during the day, put it in AC disqualify mode, this is only true way to make it more efficient, but  this defeats the whole purpose of having grid support mode!
    XW6848 inverter with 2 X mppt 60 150 CC , with Canadian solar 260Watt panels 2 x 3.5 kw array
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  • Tumi
    Tumi Registered Users Posts: 25 ✭✭
    #8
    Found this in the owners guide if it helps any. 

    Note: In grid support mode, the Conext XW+ should not draw a large amount 
    of current from the grid. If the Conext XW+ is drawing more than expected, it is 
    important to note that it cannot distinguish between real power and reactive 
    power. Large current draw will only affect reactive power and not real power, 
    and utility companies generally only charge by real power consumed.
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