Battery SOC management issues with XW gear in closed loop with Discover AES batteries grid tied

moosemountain
moosemountain Registered Users Posts: 9 ✭✭
in Solar Product Reviews & Opinions #1
I recently updated my XW system. Went from two XW+ with two MPPT 80-600 CC to two XW Pro and an Insight Home. I have a closed loop configuration with 4 Discover Battery AES  modules. They have a chip in the BMS to control the entire Xanbus network. I was off grid until two years ago. I've struggled with an issue all along of the system constantly charging and discharging the battery at the top of it's range. If I don't set a sell block schedule it will charge and sell from the grid at night. I was hoping that the Pros and Insight feature of SOC rather than voltage control would fix this but I'm still tinkering with settings to try to rein it in. Of course the partnership between Schneider and Discover created the perfect situation for crossfire finger pointing. Now, calling Schneider for help creates a language barrier that makes me miss the old days. I have a past client recently grid tied too, with different batteries, who is reporting similar observations so I'm not sure it is just the closed loop situation. Has anyone else run into this and found the sweet spot in the configuration?

Thanks.
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  • Dave Angelini
    Dave Angelini Solar Expert Posts: 6,949 ✭✭✭✭✭✭
    #2
    Which model AES ? There were 2 models and now there are at least 4.

    The next step is to ask what firmware in XWP, Insight, and the discover batteries.

    If these are the Discover 6650 batts (talk directly to xanbus) and are of different age you could have a battery issue.

    FYI, the XW+ and XWP always has had a couple hundred watt phantom load in grid tie.

    You can contact me and we can go alot further as a client.  Good Luck !
    "we go where power lines don't" Sierra Nevada mountain area
       htps://offgridsolar1.com/
    E-mail offgridsolar@sti.net

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  • moosemountain
    moosemountain Registered Users Posts: 9 ✭✭
    #3
    All components have the latest firmware.  Discover batteries are 6650 AES. I've had 3 out of 4 batteries replaced under warranty. By the 3rd one they didn't want it back. We opened it up and found the internal fuse blown and many cells looking scary. Early on they blamed the Schneider charge controls which kept falling off the network and not able to respond to battery control so presumably running wild. Shortly after that Schneider released their latest, and last, firmware release for the MPPT units which fixed the communication errors. One of my clients had a single XW+ and 3 AES 6650's. Different issues but unworkable. Scheider came back with claiming that XW+ would never work in that closed loop and actually swapped in a Pro under warranty. Discover was mute but they continue to list AES as compatiple with XW+ which I can attest to. Schneider and Discover bot screwed up by releasing this marriage half baked.  Overall it's a great concept and I still like it. When off grid it was clear that my solar harvest was considerably better. My grid sell numbers are not bad but I'm not happy cycling the batteries for no reason. This is a forum not a marketing site so I'm not interested in becoming your client but thanks for the offer.
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  • Dave Angelini
    Dave Angelini Solar Expert Posts: 6,949 ✭✭✭✭✭✭
    #4
    I have been marketing the use of this forum and the store here for many years! They do a great job of providing equipment and are great folks. I know you are new here. The only 6650 battery I know of that was damaged was from being in a hot shed too many times and unknown number of freezes. It has been replace with the rack version which is temperature stable for cold.

    I must have 10 systems still running XW+ with the 6650. The key is they can not run the BMS software only xanbus. If you upgrade the gateway/insight device you will experience problems. This has been in the forum here for the last five years and I was told this during beta testing with Schneider in 2017. XWP is the way to go for sure but if you have an XW+ and just leave it alone you will be fine. It can only run xanbus and the old fix for the open loop mppts was to set the battery max to 95% or so and lower mppt set-points. Using the Discover Dashboard would show you the real Soc and you could compare the XW+ Soc readings to see the big picture. Another big pix below😉



    There is a workaround for cycling xwp ON GRID. Below is the recommendation from Schneider and it is in the previous release note versions. This is posted (again)  for anyone with XW+ and my old clients who sometimes read my thoughts here!  Cheers! 





    "we go where power lines don't" Sierra Nevada mountain area
       htps://offgridsolar1.com/
    E-mail offgridsolar@sti.net

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  • moosemountain
    moosemountain Registered Users Posts: 9 ✭✭
    #5
    Thanks. I have two brand new XWP's replacing my xw+'s two days ago. Everything is talking fine. Discover told me years ago that the way SOC is managed is by cycling the battery within the limits set. I was hoping that upgrading and invoking SOC controls instead of voltage would give me better management. It's sunny now and I have a charge block set on the inverters. Instead when the batteries get down to 98%, where I have them set, and start to charge all solar goes to the batteries and the inverters go into grid pass through. When the batteries hit 100% the system starts to sell from solar and battery maxing out the sell capacity of the inverters.
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