Consolidated learning on Schneider sell to grid using Enhanced Grid Support and LiFePO4 battery charging without warnings, faults or odd behavior

[lopezv]

The bottom line is that the Schneider systems are extremely robust, reliable and highly configurable. It is because of this Flexibility that programming is ... difficult... especially for inexperienced DIYers like myself. While I am sure there are faulty systems out there, the vast majority of problems seems to stem from incorrect settings because the software programming layout is NOT intuitive.


I have finally gotten my system to work the way it SHOULD without magic work arounds or hardware rigging.


I was only able to accomplish this by reading a ton of input from all of the highly knowledgeable people on this forum, reading the [LATEST] manuals over and over, trial and error, AND ALOT of deductive reasoning (since the manuals from Schneider are not great, imo).


My hope with this message is to provide a useful summary of my settings and the consolidated input learned from EVERYONE on this forum in an attempt to say thanks for the help and to hopefully help other novices from giving up on these great, proven, systems.


Please keep in mind that I am NOT an expert in solar setups. I am not an electrician nor an electrical engineer. I am merely a NOVICE who has spent alot of time working through the SAME problems most of you have been having. I can only tell you what WORKED FOR ME in the hope that it will also work for your system.


My setup:
- 7.1 kw ground mount array
- Single Schneider XW Pro inverter
- Single 100A/600v Schneider mppt charge controller
- 400Ah LiFePO4 battery bank
- Schneider battery monitor

Grid support is different than Enhanced Grid Support.

Problems of the inverter cycling between charge and sell is due to 2 reasons:
- Small setup (battery and solar spec'd to min required by schneider XW Pro)
- The smaller system running in basic "Grid Support" mode rather than "Enhanced Grid Support" mode (they are different)

If using voltage to manage battery charging, most people resort to running the sell mode in voltage only (vs SOC) and setting the sell voltage on the xw pro at just above their battery bank resting voltage to prevent the XW from cycling between sell and charge while trying to sell to the grid. While this does work (and is the only option for those who have MPPT charge controllers that cannot communicate with the XW PRO), managing the charge process of LiFePO4 batteries using voltage only can be problematic. In addition, this is not the most efficient way to utilize the SELL function of the XW PRO.

Most installers will tell you that a bigger battery bank is needed (at significant cost) to stop the cycling and charging issues. Maybe, but try this first:

If using SOC or not, ENHANCED Grid Support function is the best option to get a smaller system to sell to the grid, not drain the batteries while doing it, and stop the cycling between charge and sell.

To get the XW Pro to switch from basic grid support selling to ENHANCED grid support sell, consider the following:

- The absorption charge settings of the XW Pro and the mppt charge controller need to be identical (see XW Operation Manual released 2023)
- Float charge settings of the mppt controller needs to be set a bit higher than your battery bank resting voltage (typically 54.4v)
- The SELL AMPS setting on the XW pro needs to be set very low at first to prevent cycling in basic grid support mode, then you can raise it up slowly AFTER the XW shifts to ENHANCED grid support mode.
- If using SOC, Sell SOC needs to be <100% (my system would not sell if set to >100% soc)
- Sell VOLTS setting on the XW needs to be set at 64 to 65+v (above the "equalize" setting). All this does is tell the XW Pro to switch to Enhanced grid support mode AFTER first running and passing a system sell test AT MAX SELL AMPS in basic grid support mode.
- When first started up, the XW Pro will be in basic grid support mode and will run a test by selling to the grid at the MAX sell amps setting in the XW. It WILL use the batteries and solar to do this and may drain the batteries a bit if you have a small bank and/or insufficient PV. If SOC (or voltage if not using SOC) falls below the sell setting parameters, the XW will switch back to charge and then cycle between sell and charge until the test is passed, which may never happen if it doesnt run for the duration it needs to before reverting back to charge from sell.
- The way to avoid this is to make sure all your settings are correct (see page 101 of the 2023 XW Operation Manual) AND lower your sell amps to a level that your batteries and solar can handle for the longest duration possible without a significant SOC or voltage drop (also may help to try startup on a high PV day with low sell amps)
- If the XW sell test is passed, the XW will automatically switch to ENHANCED grid support mode which then uses the data (volts and available DC amps) from the mppt controller to manage the sell function. This will allow the XW to use the DC amps coming from the mppt charge controller to dictate how much power to sell after having sufficient PV to charge batteries and managing AC loads. The max sell amps setting in the XW pro will then only be used as a ceiling for the system sell amps (ie, it will sell excess DC output from the SCHNEIDER MPT charge controller after determining it has sufficient DC to charge batteries and support AC loads) .
- At that point, you can raise the max sell amps setting in the XW pro to whatever the max your PV array and mppt controller can pump out at max PV @ FLOAT voltage. My 7kw array and 100amp charge controller puts out about 5.5 kw max DC @ 54.4v at full sun. This converts to about 23A@ 240v AC, so I have my max sell amps now set at 25A after running the initial startup test at about 10A.

My small system now wakes up in the AM, uses available PV to charge the batteries, then, once sufficient DC output is available from the PV array to maintain batteries and support AC loads, the XW starts to sell excess PV to the grid while maintaining the batteries just above their resting voltage all day.

When using the XW Pro to charge the batteries from the grid, it will use the SOC setting on the battery monitor (rather than voltage) to prevent overcharging risks of charging by voltage only. If using voltage only, recommend limiting the absorption duration time while charging at a voltage no higher than 56.8v (48v LiFePO4 battery setup).

NOTE: The schneider mppt controller uses voltage only, regardless of the installation of a battery monitor. Again, absorption voltage settings of the MPPT charge controller and the XW must be the same for the Enhanced Grid Support function to work.

 

[Quattrohead]

The bottom line is that the Schneider systems are extremely robust, reliable and highly configurable. It is because of this Flexibility that programming is ... difficult... especially for inexperienced DIYers like myself.

Thanks for giving back to the community.
This particular sentence can be applied to all solar systems, more people should remember this before taking on a big, powerful and dangerous project.

 

[GRMRC]

Hello all,
This is going to be a long message, so I apologize in advance.

I am a new member of the forum but have been reading and using the info from here for about a year trying to get my Schneider XW Pro system working correctly.

The bottom line is that the Schneider systems are extremely robust, reliable and highly configurable. It is because of this Flexibility that programming is ... difficult... especially for inexperienced DIYers like myself. While I am sure there are faulty systems out there, the vast majority of problems seems to stem from incorrect settings because the software programming layout is NOT intuitive.

I have finally gotten my system to work the way it SHOULD without magic work arounds or hardware rigging.

I was only able to accomplish this by reading a ton of input from all of the highly knowledgeable people on this forum, reading the [LATEST] manuals over and over, trial and error, AND ALOT of deductive reasoning (since the manuals from Schneider are not great, imo).

My hope with this message is to provide a useful summary of my settings and the consolidated input learned from EVERYONE on this forum in an attempt to say thanks for the help and to hopefully help other novices from giving up on these great, proven, systems.

Please keep in mind that I am NOT an expert in solar setups. I am not an electrician nor an electrical engineer. I am merely a NOVICE who has spent alot of time working through the SAME problems most of you have been having. I can only tell you what WORKED FOR ME in the hope that it will also work for your system.

MESSAGE TO EXPERTS:
FEEL FREE TO CORRECT OR ADD TO THIS INFO AS YOU DEEM APPROPRIATE.

The following is a summary of my settings and my understanding of the [probable] functionality for sellIng to grid, using Enhanced Grid Support and battery charging for a Schneider XW Pro inverter with a Schneider 100A/600v MPPT charge controller, a 400Ah LiFEPO4 battery bank and 7kw solar array using either SOC or voltage to regulate charging and Grid Support functions.

System Setup:
Single, stand alone, Schneider XW Pro 6848 (USA config).
Schneider 100A/600v MPPT Charge Controller
Schneider Battery Monitor
7100w ground mounted PV array set about 300 ft from the equipment.
System is grid tied, DC coupled with an active utility agreement to sell to grid.
Beyond selling to the grid, the system is used for backup power only. All PV is sold to grid when grid power is available and all AC loads are regularly supported by the grid. When the grid goes down, an external transfer switch is used to tell the XW to stop selling and support all AC loads using the inverter. Off grid loads are managed manually via subpanel breakers.

MY Battery Setup:
16 SOK 12V100A LiFePO4 batteries (4 batts in series × 4 banks in parallel, 400Ah total capacity)

Managed by individual internal BMSs (NO COMMS), External batt balancers on each bank (to balance each 12v battery in series)

Schneider Battery Monitor used to manage SOC of the entire bank of 16

(yes... i should have just bought 48v server rack batteries from the start).

Batt bank specs:
Total capacity: 400Ah (4x 100Ah batts in parallel)
Total batt volts with fully balanced cells: 57.6v (14.4v x 4 in series)
Max batt: 58v (14.5×4)
Batt over v BMS disconnect: 58.4v (14.6x4)
Batt rest: 53.2v (13.3x4)
Recommended charging current: 80A (20A/batt)
Max DC charging current: 200A (50A/batt)
Max DC discharge: 240A (set in XW, limited by breakers)

My solar array setup:
2 strings of 10 x 355w panels (20 panels total) for 7100w PV (theoretical). ACTUAL PV output at the Schneider MPPT controller is about 6kw @ max PV and 5.5KW of usable DC power @ 100A DC from MPPT.

SETTINGS:

Schneider Battery Monitor:
100% SOC: set to 53.2v (resting voltage of batt bank)

XW Pro Charger and Battery Settings:
Battery type: Custom
Battery size: 400Ah
Charger: 2 Stage only
Batts SOC: ON (set to off if using volts only)
Bulk: 55.2v
Abs: 55.2v for 10 min
Recharge: 50v
Recharge SOC: 30%
Low volt cutout: 49v
Low SOC cutout: 25%
Batt type: Custom
Equalize: OFF
High batt cutout: 58.4v
Max Charge Rate (% of 140A max DC charging output from the XW PRO): 57% (80A or 20A/batt)

XW Pro Grid Support Settings:
Grid support: ON
Sell: ON
Sell SOC: 99%
Sell volts: 65v
Export Power Block Start: 8pm
Export Power Block End: 8am
Grid support max sell amps: 25A (for 6-7kw array, 400Ah batt and 1 MPPT controller)*

MPPT Charge Controller Charger and Battery Settings:
Charging: 3 Stage
Batt size: 400Ah
Batt type: Custom
Bulk: 55.2v
Abs: 55.2v* (must be exactly the same as XW)
Float: 54.5v
Recharge: 50v
Equalize: OFF
Charger DC available: 100% (100A)


CRITICAL NOTES:

BATTERY MANAGEMENT NOTES:
- If using an external battery monitor (HIGHLY recommended), the setting for 100% SOC must = (or be close to) the battery RESTING voltage of your battery bank. You need to find this by fully balancing your batteries and then letting them rest overnight while they are disconnected from all loads other than the minimal needed to run the solar equipment. Then, once rested, reset the monitor to 100% SOC at that rest8ng voltage BEFORE any charge or load is placed on them.

If you are using a battery with a closed loop external BMS, then you MUST know what VOLTAGE the battery BMS considers 100% SOC (This will likely be its resting voltage).

The FLOAT voltage of the MPPT charge controller needs to be set slightly higher than the resting voltage of the battery bank. My batt rests at 53.2v. I have float on the MPPT controller set to 54.5v. This keeps the batteries just above resting voltage (100% charged) during SELL to grid.

- If using CLOSED LOOP with Ext-BMS ON and batt type set as Li-Ion, the XW Pro MAY AUTOMATICALLY reconfigure some charger settings in the XW PRO ONLY to match the BATTERY manufacturers settings in the BMS. This can cause a difference between charge settings in the XW and the MPPT charge controller. The abs settings (at least) MUST be the same between the inverter and the mppt charge controller, so double check everything every time any change is made and mske sure your charge settings are the same in both components.

- Some people have reported that their battery BMS settings were not working properly with the system or seemed incorrect in closed loop (Ext BMS ON). If this happens (incorrect BMS data being relayed to the XW) then set BATTERY TYPE to CUSTOM, with External BMS ON, SOC ON, and reset all charger parameters manually (keeping the MPPT controller ABS setting (at minimum) consistent with the XW PRO settings.

- High Batt cutout voltage on the XW MUST be set >3v above your highest charge v setting (typically, the ABS phase setting) in order to prevent an over voltage WARNING. An over voltage FAULT is different and is a real concern. As far as I am aware, the FAULT level is hard coded into the firmware and is NOT controlled by the HBCO setting and the high batt cut out setting (HBCO) only controls the WARNING messaging. HOWEVER, this is NOT clear so I set my HBCO voltage as close to the actuall BMS cutout as possible to not trigger a false warning but not so high that it will never notify me of a true high volt condition, just in case (despite direction of schneider support to just keep raising it up). If your equipment is functioning properly and your settings are correct, the system should NEVER over volt.

- The DC output % for charging setting on the XW Pro (Maximum charge rate setting) is a percentage of the total AMPs that the XW Pro can charge at. For a single XW pro, this max is 140A. My batts prefer 20-50A each, so my setting is 57% of 140A or 80A ON THE XW.

- The Schneider MPPT controller charger provides up to 100A of DC current. The actual current at any given time will depend on the amount of solar available at that time. The max DC amps available from that charger can be limited via settings on the MPPT controller, if necessary. If your array large enough and your batteries can handle it, recommend setting this to 100% since limiting the DC output from the mppt controller will REDUCE the amount of DC current made available to the XW inverter to SELL to the grid, support loads and for charging the batteries using PV. HOWEVER, if your battery bank CANNOT handle the full 100A then you MUST limit the charge controller output (and the XW DC charge output) to match the total AMPs your bank can handle.

- If you have lithium batteries using SOC (optional on XW pro) or voltage only (MPPT controller) to control charging, you should use the Absorption Time setting function to limit the duration of the absorption phase of the chargers to avoid over charging. Set ABS time to a duration as short as necessary to charge the batteries to the level you want. This should be done on both the XW and the MPPT controller. If you do not limit the ABS Time, there is a high probability that the Abs phase will not end before the BMS of ONE of the batt reaches its HBCO voltage, triggering a voltage SPIKE (especially when charging from the XW pro charger), a cascading shutdown of thebother batteries and either an over volt warning or over volt fault / shutdown can result. This may not happen every time, but it WILL eventually happen, especially if the cells of each of the batteries are not all kept well balanced.

- When using lithium batteries, NEVER set bulk charging volts HIGHER than the absorption volt setting. Setting bulk v higher will tell the charger to use the "BOOST" charging function which can significantly extend the duration of the ABS charge phase. The boost function will HOLD the charging volts and amps at the max for 1 hour BEFORE switching to timed absorption. SO...Set bulk voltage to slightly lower or the same as ABS voltage and adjust the ABS TIME setting DOWN to manage when the charger ends the process (XW) or switches to FLOAT (MPPT controller). I have mine set to 55.2v for BOTH bulk and ABS phase with ABS ending after 5 minutes on the MPPT and 10 min on XW Pro.

- Some battery specs require a higher voltage than 55.2v to top balance the battery cells (usually around 58v). The issue with this is that there is typically very little voltage differential between top charge and HBCO on LiFePO4 batts. So, if youre using VOLTAGE to regulate charging (especially on the XW via grid power) and want to top balance your battery cells, youll need to play around with the ABS time/duration setting to find a sweet spot where the voltage of the ABS phase is high enough to top balance all the cells but the DURATION is short enough to NOT overshoot the HBCO of the battery BMSs. Dont forget that the HBCO warning setting on the XW Pro needs to be >3 volts higher than the top balanced voltage of the battery bank to prevent a HBCO warning. I have found that adding a BATTERY MONITOR was worth the additional cost to prevent any potential over volt faults by managing via SOC instead of voltage only and would recommend you do the same.

- If youre still getting an over volt warning, you can limit the absorption exit parameters to TIME ONLY and/or lower the charge voltage of BULK and ABS or raise the HBCO setting on the XW pro (not recommended) or purchase a batt monitor.

- If youre using lithium batteries and managing charging via volts and you dont want to lower the charge volts of the charge stages (to be able to top balance, for example) then you can also limit the absorption charge EXIT parameters to TIME/DURATION only (rather than current OR time) AND manually controll the charge CURRENT (AMPS) for each phase. For example, run bulk at high amps and lower voltage than full and run ABS at a high voltage (tontop batts) but much lower current (AMPS). To do this, set battery bank size To ZERO in the battery settings of the XW pro. THEN recheck all other settings to ensure nothing was changed AND manually reset the charge current for EACH charge stage. NOTE: It is my understanding that using ABS time only (setting battery bank Ah size to zero) WILL change the CHARGING AMPS used for all phases to "default", which is 140A, if you dont adjust the current for each phase of charge manually under this setup, so be careful to manually set these parameters according to your batt specs.

- The XW Pro adds 3 minutes to whatever you set as the max duration for the absorption phase, keep this mind when testing your settings (your setting time for max duration in abs charge stage + 3 min = actual MAX time the system will spend in ABS phase).



ENHANCED GRID SUPPORT AND SELL FUNCTION NOTES:

- Enhanced Grid Support REQUIRES the use of a SCHNEIDER CHARGE CONTROLLER with the XW PRO inverter or a mppt controller with compatable comms. They MUST be able to communicate for enhanced grid support to work.

- ABSORPTION charge stage settings (at minumum) on the MPPT MUST be exactly the same as what is set in the XW pro for ENHANCED Grid Support to function correctly.

- Grid Support voltage must be set to 65v (possibly 66v on some builds) to enable ENHANCED Grid Support function. This setting SHOULD work if using voltage only or SOC IF all other settings are correct. if settings are not correct ANYWHERE, the system will NOT go into Enhanced Grid Support and odd things will happen.

- The MPPT controller uses VOLTAGE to regulate the charging process AND the sell function parameters under Enhanced Grid Support. It does NOT USE SOC AT ALL. The SOC settings in the XW Pro are ONLY for the XW PRO CHARGER (used ONLY when AC coupled OR charging from the grid) and to tell the XW Pro that the battery bank is READY to sell. After an intial sell test AT MAX SELL AMPS conducted by the XW Pro, sell control is handed off to the MPPT controller In ENHANCED Grid Support mode.

- In ENHANCED GRID SUPPORT, the max sell amps setting is an UPPER LIMIT for the AC side of the sell function. BEFORE the XW pro allows Enhanced Grid Support function to operate, the MAX sell AMPs setting is used by the PRO to TEST the sell function to the grid. So... even if you enable the Enhanced Sell Function on the XW Pro (sell volts = 65+) the XW will NOT engage it until AFTER it completes and satisfies an initial test at max sell amps to the grid. In addition, for PV to be sold to the grid, the MPPT charge controller must have reached FLOAT stage of charging.

- Enhanced Grid Support (sell volts setting = 65+) will LIKELY cycle between charge and sell during its initial TEST of the grid sell connection IF you have the Max Sell AMPS (AC side) set higher than the mppt charge controller is providing (on the DC side) AND if you have a battery bank on thebsmaller side (minimum of 400Ah required by schneider). This will continue until the XW pro has tested and satisfied the grid connections ability to safely sustain a sell at max amps, system comms are good, AND charger settings of the mppt controller AND XW Pro are in sync.

After the initial test, IF PASSED, the sell function control is given to the MPPT Controller. At that point, the SELL function will only initiate again IF the battery Sell SOC is above the sell SOC setting (if using SOC) or the batts are at or above the mppt controller FLOAT volts (if using voltage only) AND the MPPT controller has entered the FLOAT charging stage. If all is working properly at that point, upon waking up, the system should first use available PV to recharge the batteries to above float, then switch to float stage charge on the MPPT controller and start selling remaining PV to the grid (after satisfying any other AC loads).

- After an initial test at MAX AMPS, the available DC from the MPPT controller will decide what the total power to sell will be (limited to 100A DC on my 1 charge controller). Again, the Absorbtion setting MUST be identical in both the mppt controller AND the XW pro, the sell volts needs to be set to 65-66v and SOC (IF USED) needs to be 99% or lower (mine would not sell if set to sell at SOC of 100%) in order for enhanced grid support to work.

- The SELL AMPS setting on the XW Pro (AC @ 240v) IS CRITICAL. It should be set for no higher than your battery bank can handle AND your array and charge controller can provide (max DC amps @ FLOAT voltage).

As noted above, when you FIRST enable the sell function (or re-enable it after changing anything) the XW Pro will TEST the sell function at MAX SELL AMPS. If there is low solar output or your max sell amps are too high for your batt to easily handle... or both... then the XW Pro WILL pull AMPS OFF THE BATTERY to reach the max sell AMPS setting. This SHOULD settle down as the available solar DC output amps increases and enhanced grid support engages but only IF your settings are correct (as noted above). This will require some conversion math or a tool (readily available on the net) for converting DC to AC, amps and watts to get the DC to AC settings in sync... or, just set the sell amps LOW, and then rise it slowly after Enhanced Grid Support is engaged.

For my setup, I have a 400 Ah battery bank, a 7kw array and a 100A charge controller. So, @ max solar (about 6kw) my charge contoller is pushing out the full 100A @ FLOAT voltage (54.5v). When that 100A is converted to AC @ 240v, the XW pro pushes about 20-21A to the grid. However, I have my Sell Amps set for a full 6kw (25A @ 240v). If the XW Pro is first started up during low solar, The XW Pro WILL draw all needed amps from the battery to test the SELL function (6kw; 25A @ 240v, as per XW setting) at the max sell amps setting. If the batteries fall below sell SOC (or float voltage setting in voltage only mode), the XW will cycle between charge and sell until the parameters of the test are satisfied. If your settings are incorrect, this cycling will never settle down because the XW Enhanced grid support function will NOT hand sell control over to the MPPT controller and the sell load will not be reduced to match that of the solar charge controller output, as it should do under normal operating conditions.

- If all your settings are correct, once the enhanced grid support function settles down and hands off control to the MPPT controller, the SELL function will start selling only what the Mppt charge controller can provide and ONLY after the MPPT charge controller enters FLOAT stage.

Remember, the SOC setting on the XW Pro has NOTHING to do with this. The MPPT will only go into float when the battery VOLTAGE reaches a point to complete a BULK AND ABSORPTION charge cycle... For my setup, this is about a volt ABOVE what the batt monitor registers as 100% SOC. (Mppt float: 54.5v, batt-monitor 100%: set to 53.2v). SO... the SELL SOC in the XW (telling the XW that the batteries are ready to sell) is already triggered (parameter met) BEFORE the sell function starts (mppt in float).

In my configuration, the mppt controller will first top off the battery, then 5 minutes after absorption starts it will change to float and (if the XW sees SOC is above 99%) will start selling UP TO 100A DC@54.5v (roughly 20-22A @ 240v) as the solar availability allows.... It MAY use some low amps from the battery at first, until the software functions, voltage, frequency and amps stabilize, then the batteries go into STANDBY and are only used slightly again if needed to keep things stable (usually no more than a few hundred watts for a few seconds).



So... with my current settings, heres an overview of how my system IS NOW functioning:

Upon Initial startup, with a fully balanced and fully charged battery bank, early in the morning with low solar output, the sell function pulled a full 6kw (25A @ 240v AC) from the batteries for a few minutes. Because the solar was low output, almost 100% of that 6kw was from the batteries (the 25A draw was based on my max sell AMPS setting in the XW). This caused the system to bounce back and forth between charging the battery bank (as charge fell below 99%) and selling power to the grid. I adjusted the SELL MAX AMPS DOWN to greatly reduce the cycling. The draw on the batteries also slowly came down further as the DC AMPS from the charge controller became available. After some time, enhanced grid support stabilized and switched control of sell variables over to the MPPT charge controller. This allowed the charge controller to dictate to the XW how much to sell, based on solar output alone. At that point, the sell amps (AC) dropped in line with the solar output (DC) and remained fluctuating relative to PV output. At that point, I reset the Max Sell Amps on the XW to 25A (as it was operating). As the AC sell AMPS fell below the max 25A, the sell function no longer drew any significant AMPS from the battery bank as the amps were being controlled by the MPPT output, NOT the XW settings.

The following day, when the MPPT controller woke up, it firsr pushed available PV to charge the batteries. When the batteries reached the VOLT, amp and time duration settings for Absorb, the MPPT controller switched to FLOAT and started to sell to the grid again. At first (about 10 min or so) the sell function pulled about 200w off the batteries (basically took them back down to a bit below float voltage and just above their resting voltage (around 53.7v) and they went into stand-by with zero amp draw. Occasionally, the sell function would pull about 100w or so along with the PV DC, I assume to keep all sell function parameters stable (frequency, etc).

- After the sun goes down, the MPPT controller remains in float phase of charge for over an hour because the batteries are still above the resting voltage of the bank (resting v= 53.2v; End of sell day v= 53.7v). Because the mppt controller is in Float AND the batt SOC level read by the XW pro is higher than 99%, the XW Pro MAY try to continue to sell to the grid using the batteries only (the full 25A, 6kw power) until the SOC falls to 98%. This is a minor issue when using SOC control but may be a major issue for those who are regulating the charge cycles using voltage only (IN ENHANCED Grid Support mode) since the XW may continue to sell to the grid until the discharge floor setting of the batteries is reached. Then, it will likely use the GRID to recharge the batteries overnight, essentially repurchasing all of the power the batteries just dumped.

The way to prevent this is to limit the sell time in the Grid support settings to only sell during the day when PV is being produced.

Sell Block on (selling stops) at 8pm
Sell Block off (selling starts) at 8am

If SELL BLOCK function doesnt work for your setup when operating using voltage only, you can try 2 other solutions:

- Try increasing the recharge voltage OF THE MPPT CONTROLLER ONLY to just below float voltage. This MAY kick the mppt out of float phase and into bulk charge after a short sell. Once the voltage drops below recharge V (now set to just below float) and the mppt goes into bulk, it should stop selling and remain in that state until the sun comes up the next day. In the morning, it should quickly run through the charge cycle and start selling again once the mppt controller switches back to float phase.

If all else fails and you've just had enough, then you can try running sell without Enhanced Grid Support function at all by setting the SELL VOLTAGE setting on the XW Pro to just above the resting voltage of your batteries and setting the mppt FLOAT voltage to just above the sell volts setting. I have also run my system this way for months before I had the battery monitor. The system wakes up when the sun hits the array, the batteries are taken up to float voltage and then it immediately sells available PV to the grid after that. When the sun goes down, the selling stops immediately.


Truely hope this makes sense and helps you all.

There is so much wrong information in here with respect to Enhanced Grid Support, SOC and Float.

 

[42OhmsPA]

MESSAGE TO EXPERTS:
FEEL FREE TO CORRECT OR ADD TO THIS INFO AS YOU DEEM APPROPRIATE.

There is so much wrong information in here with respect to Enhanced Grid Support, SOC and Float.

 

[GRMRC]

Grid Sell happens during Bulk, Absorption and Float as long as SOC is above Grid Support SOC.
65v setting to enable Enhanced Grid Support is laughable and is not required.
For those of us with more than one XWpro there more options for maximizing AC production and Grid Sell regardless of PV production from the 600/100’s.

I just wonder why people try to make things more difficult than it needs to be with all these “you must do this” type statements.

 

[lopezv]

Grid Sell happens during Bulk, Absorption and Float as long as SOC is above Grid Support SOC.
65v setting to enable Enhanced Grid Support is laughable and is not required.
For those of us with more than one XWpro there more options for maximizing AC production and Grid Sell regardless of PV production from the 600/100’s.

I just wonder why people try to make things more difficult than it needs to be with all these “you must do this” type statements.

Never said that "grid support sell" would not sell to the grid under bulk, abs or any other mppt charge controller setting when in THAT mode. "Grid Support" uses the settings in the XW ONLY. So, if you set SOC SELL to 99% it will sell, BUT its going to do it at the MAX AMPS set on the XW and drain the batteries down until they fall BELOW sell SOC (unless there is sufficient solar production and batts to handle the full load).

In "ENHANCED Grid Support", The XW will use the settings of the MPPT controller to determine what to SELL (AMPS) and how to sell (float voltage).

The XW is told to initiate Enhanced Grid Support if the grid support voltage setting is set above 65+v.

The XW will only change from "grid support" to "Enhanced Grid Support" AFTER it runs a test at max sell amps. This takes time. I dont know how long.

If youre running your system in basic "grid support" mode (Grid Support set to ON AND Grid Support Voltage below 65v (actual should be much closer to batt resting V in this case) the XW will likely fluctuate between sell and charge (using all sources) as the battery bank rises and falls above and below the sell parameters (voltage OR SOC) set in the XW.

If you run sell to grid in "Enhanced Grid Support" then the MPPT Charge controller must be in FLOAT AND XW must have SOC above sell SOC setting (only if using SOC) before it will sell IN ENHANCED GRID SUPPORT and the XW will use the settings in the MPPT controller to manage the sell rate and voltage.

 

[GRMRC]

Never said that "grid support sell" would not sell to the grid under bulk, abs or any other mppt charge controller setting when in THAT mode. "Grid Support" uses the settings in the XW ONLY. So, if you set SOC SELL to 99%, it will sell, BUT its going to do it at the MAX AMPS set on the XW and drain the batteries down until they fall BELOW sell SOC.

In "ENHANCED Grid Support", The XW will use the settings of the MPPT controller to determine what to SELL (AMPS).

The XW is told to initiate Enhanced Grid Support if the gris support voltage is set above 65v.

The XW will only change from "grid support" to enhanced grid support AFTER it runs a test at max sell amps. This takes time.

If youre running your system in baeic "grid suppor on" mode, the XW will likely fluctuate between sell and charge (using all sources) as the battery bank rises and falls below the sell parameters (voltage OR SOC).

If you run sell to grid in "Enhanced Grid Support" then the MPPT Charge controller must be in FLOAT AND XW must have SOC above sell SOC setting (only if using SOC) before it will sell IN ENHANCED GRID SUPPORT.

My system will grid sell continuously for 5 - 7.5 hours depending on length of day. Loads are met, batteries are 100% SOC and excess PV gets sent to grid. I routinely produce more kWh than I consume. True Up is <$0. You are welcome to run your system however you want.
I would suggest there is a great deal more for you to learn about these DC coupled Schneider systems.

 

[lopezv]

I am very happy for you.

ENHANCED Grid Support mode is especially useful for people who have smaller setups, like mine (1 Inverter, 1 MPPT controller, 7kw array, 400Ah battery bank).

Your system is apparently large enough to support all loads without a significant battery draw when selling at MAX amps OR your sell amps setting is very low, or both. But your system is not operating in "Enhanced Grid Support" mode. It is operating in basic "Grid Support", which sells at max amps USING THE BATTERIES if the sell AMPS setting is higher than what the PV is providing throughout the day BECAUSE it is only using the XW settings (max sell amps) and not adjusting for the data from the MPPT controller (ie, letting the mppt controller manage the sell function).

 

[GRMRC]

I am very happy for you.

ENHANCED Grid Support mode is especially useful for people who have smaller setups, like mine (1 Inverter, 1 MPPT controller, 7kw array, 400Ah battery bank).

Your system is apparently large enough to support all loads without a significant battery draw when selling at MAX amps OR your sell amps setting is very low, or both.

Yes. I designed the system to meet my power consumption needs AND zero my electric bill. The system was physically over paneled slightly.
It is currently configured to be “electrically” over paneled as well. Rather than needing 1,000 W/m^2 to produce kWp nameplate power, I am producing and exporting power with anything above 450 W/m^2. My system as configured is very tolerant to overcast days and bypassing clouds. As currently configured I produce 1.6x the kWh I consume which is the amount needed to zero out true up and NOT power the whole neighborhood. Details of my system can be found in the sig below.