My choice of buying the Schneider XW Pro with MPPT 100 600 charger was based upon the reputation of the hardware reliability. And I have to say that the hardware has been flawless thus far. It still amazes me that the inverter even fires up my 6 HP air compressor which has a locked rotor current of 94 amps.
However, my overall experience has been disappointing because of the horrible firmware! It has taken me a full year to figure out various tweaks to make the system work right.
I am writing this in hopes that others using this system can benefit from my very expensive education in all things Schneider Solar. If you are using this equipment in an off-grid way, then this does not apply to you. This post deals with exporting to the grid and how badly XW Pro handles it.
My configuration:
I found this to work quite well and would be curious if others found the same settings or if you had a cycling system and you implemented these settings if it would work for you. I should add that a friend of mine has an identical system as mine, and it worked for him as well.
However, my overall experience has been disappointing because of the horrible firmware! It has taken me a full year to figure out various tweaks to make the system work right.
I am writing this in hopes that others using this system can benefit from my very expensive education in all things Schneider Solar. If you are using this equipment in an off-grid way, then this does not apply to you. This post deals with exporting to the grid and how badly XW Pro handles it.
My configuration:
- One XW Pro inverter
- One XW MPPT 100 600 charger
- Four EG4-LL LIPO4 batteries
- Insight Home
- My system is grid-tied
- Batteries are only used for backup purposes
- Sufficient solar panels to provide all the power I consume and then some
- Schneider documentation does not match the current firmware.
- Schneider support has never been of any help, even though I have logged at least 25 hours on the phone. They have been only incidentally helpful by providing certain hints which allowed me to go on experimenting on my own.
- There are numerous bugs and “undocumented features” in the firmware.
- The batteries are capable of closed loop interaction but the system does not work properly… so I run them in “voltage control”.
- I recognize that my main problem stems from the fact that I am grid tied. I believe for people that are completely off-grid can make the system work just fine.
- While exporting power, and if there is not sufficient power from the panels because of a cloudy day, the system “cycles”. In other words, it does the following:
- House is powered from the grid, while the battery is allowed to charge up to the “grid support voltage”. Once that voltage is reached, the inverter consumes power from the DC bus by using energy from the panels and the battery… the inverter “thinks” there is lots of power available and ramps up the grid export current to the export amps setting.
- This quickly discharges the battery to be below, the “grid support voltage” and the inverter stops using power from the DC bus and entirely powers the house from the grid.
- This crazy cycle keeps repeating! If you look at the graph of the “battery summary” you will see a crazy loop of charge/discharge… repeat.
- There is a cryptic note in the firmware release notes for the XW Pro that indicates this is a known problem.
- It is now the end of April 2024! In July 2023 I have been told by the tech support that there will be a new release that will fix this problem. I am still waiting and all we have is crickets! I have heard rumors that Schneider is “abandoning” this product line…. I sure hope this is a false rumor!
- Forget closed loop operation (turn off SOC control) and just run this in “voltage control”
- Set the charger in the MPPT for 3 stage charging and the charger settings in the inverter to 2 stage. (even though the Inverter charger will not be enabled)
- In the MPPT, set the Bulk, Absorb and Float to 54 volts (this is for the EG4-LL batteries, modify accordingly to other batteries) Set the same voltages in the inverter charger.
- In the MPPT set battery capacity to 0. This will prevent absorb switching to float based upon voltage and will only switch based upon the timer setting which must be set to the maximum time of 8 hours (setting is in minutes).
- In the inverter, set the Grid support voltage to 53.5
- For what ever crazy reason, the cycling only takes place if the charger in the MPPT is in Float mode! So the objective is to keep it in Bulk or Absorb! However, my solar day is longer than the maximum timer setting of 8 hours! So, we have to trick it to go back to starting the charging cycle all over again. This is done by setting the Recharge voltage to 53.7 (this works for me put you will have to play with this depending on your system size, etc.) So what happens is that after the 8 hours, the system switches to Float and the voltage will drift down (don’t ask me why since all charging mode voltages are the same). When the voltage goes below the Recharge voltage, the charging cycle will begin all over again and the timer for the Absorb to Float will be reset.
I found this to work quite well and would be curious if others found the same settings or if you had a cycling system and you implemented these settings if it would work for you. I should add that a friend of mine has an identical system as mine, and it worked for him as well.