XW+ 6848, 48v bat bank, use grid as backup

Hello there, i have my XW+ installed, everything is working great, Since I have the grid line connected to the inverter, I want to set up the Grid Support, no selling, only to allow the batteries to charge if during the night they get to 50%, could anyone please explain a bit how to do this, I have read the Owners Manual but I don't quite get the instructions there.
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Many of the settings interact with others, setting the battery size/amp hours is one that is critical
|| Midnight Classic 200 | 10, Evergreen 200w in a 160VOC array ||
|| VEC1093 12V Charger | Maha C401 aa/aaa Charger | SureSine | Sunsaver MPPT 15A
solar: http://tinyurl.com/LMR-Solar
gen: http://tinyurl.com/LMR-Lister ,
Grid Support enabled
under Advanced options
Grid support V try 48.4
sell disabled
I prefer to leave the charger disabled. A hard load that dips the battery voltage for more than a few seconds can activate the charger when the batteries are still a bit above your desired 50%. But if you want to leave the charger enabled I'd start with Battery recharge V at 48.2v and go from there.
Do not totally rely on your SCP or Combox battery meter. If you've got LA batteries use the SG readings regularly. good video If you run LA batteries https://www.bing.com/videos/search?q=rolls+schneider+battery+video&view=detail&mid=AF89235D2A45973D0423AF89235D2A45973D0423&FORM=VIRE
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
With your LBCO set at roughly 50% SOC and a desire for grid charging to enable at roughly the same point I'd make sure your LBCO delay is fairly long, like the 300 second max.
I set my LBCO at 47.2, about 30% SOC. Long power outages are common here, often we don't notice that the grid has been down for over a day. If the neighbors don't have power we often don't notice because the neighbors are too far away to hear a generator and nobody panics because power outages are common. The well pump may run dipping battery voltage so I went with the long 300 second delay.
May I suggest that instead of having the charger automatically cutting on you instead enable grid support. The inverter will pull about 80 watts constantly but with grid support voltage set at about 49.4v your inverter will automatically increase the use of grid voltage to supplement the battery power until it goes almost totally to grid power with very little drain on the battery when the battery gets below the set voltage. 49.4v works out to about a 70% SOC battery before the grid fully steps in and handles 98% of the load.
The roughly 100 watts is about 2.5 kwhs/day so about 25 cents a day worth of grid power used each day that the batteries stay above the set voltage.
By enabling the charger manually if you know the next day will be sunny you don't need to charge the batteries. It won't really hurt your batteries to let them sit a day at 70% waiting for the next sunny day. Your grid support will keep the house powered.
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
https://www.bing.com/images/search?view=detailV2&ccid=sGyHUY6z&id=D6CCC788AE313D7E651F7083060AFC8C616481B0&thid=OIP.sGyHUY6zuCW8XVq0YE9lsgHaDy&mediaurl=http://modernsurvivalblog.com/wp-content/uploads/2013/06/battery-state-of-charge.jpg?x12845&exph=333&expw=650&q=battery+state+of+charge+chart&simid=608012370959467216&selectedIndex=0&ajaxhist=0
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
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