Hello everyone,
I have had some odd behavior happening with my 6000xp inverter specifically on the charging once the battery reaches max voltage. For reference I am using a lithium-Ion battery (14s 51.2v nominal) with 6000 watts of useable storage that has a 100 amp bms. While I do realize that my battery a bit under sized for my setup the Inverter should still handle these issues better.
With charge settings at 58.8volt max and 58.0v float.. The follow occurs: The pack charges normally until voltage hit 58.5-58.8 ever so breifly then charging stops for about 2-3 seconds then charge ramps back to full utilizing all available PV. Ramp up takes about a few seconds until max voltage is hit again then repeats..
In attempts to negate this behavior I lowered the max voltage to 58 and float to 57.5.. This setting is better behaved however at times I do still see pulse charging ie. input charge drops by upto 500 watts then back to full in 3-5 second intervals. Again for reference my bms app updates in 1 second intervals.
Now while the charging annoying and does not seem to follow a proper CC/CV charging profile the second issue is much worse.
On the discharging side of things.. I have my On Grid EOD Voltage set to 48 volts. Also not having a settable return to battery voltage field makes this huge problem even more so in the winter. Once the battery pack discharges to low state sub 20% capacity remaining a 1500-2000 watt load does make the battery voltage sag a good amount usually around 1-1.5 volts depending on the draw. With lithium-ion the voltage curve is not as flat as Lifep04 batteries and also after the load is removed the battery pack does recover upto 2 volts in many cases.
The behavior I have been seeing is as follows: battery reaches 48v. Inverter transfers to grid and now that the load is off the battery voltage increases to 49-49.5 or 50V in cases of heavy loads removed. battery creeps back to 51v and Inverter transfers back to battery and the cycle repeats.. Usually this cycle happens once every 5 to 10 minutes until the last 10-15 amp hours of the battery has been used and does not recover to 51 volts. With this being winter time my mini-split will use more power at night and as the battery gets lower I have seen this cycle be as low as 5 seconds. This 5 second cycling has occurred at least 3 times in which I had to step in and change discharge settings.
In an attempt to stop this cycling effect I have enable ac charging to start at 48v and stop at 57v with a charge setting of 1 amp.
I have had a 6000xp for about 10 months. The first unit fine for about 3-4 months then developed an issue an was rma'ed after extensive back and forth. The first unit did show the charging issues from above however I did not see the discharge to grid issues. I will also say the first unit was on the previous firmware from the current as of today except for the last week before the RMA.
My current unit has always been on this latest firmware.
I would like to hear what the expect behavior should be for both of my issues.
Thanks
Jared Spires
