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so is it solved ?

@TaliaB I have been busy lately and haven't been following the forum. I wish you a full recovery.

Interesting What about your home battery BMS

I see your point In general, smartphones , EVs .., etc tend to decrease the charging rate in based in the SOC or the voltage, And I have found that my BMS do the same , so I am wondering if this feature useful in home LFP case or it only applies to NMC , lithium polymer in phones or LFP but with 2C car super fast chargers

@TaliaB @Stefan Cornelissen @Steve87 @Beat I’ve changed the requested charging voltage from the battery side to 56 volts. Since then, I’ve noticed an improvement. It appears that the BMS only balances the battery when there’s charging current, and the battery SOC isn’t 100% (maybe). Now the delta dropped significantly

I’m curious about BMS designs that gradually reduce the charge current based on State of Charge (SOC), rather than the normal tapering that naturally occurs as the battery voltage approaches its final value. ( like what iPhone battery controller do after 80%) For example, some BMS limit the current to 20A during the last 15% of charge regardless of the voltage. Has anyone used such a BMS? What are the pros and cons? Does it affect cell balancing or battery performance?

Here are the steps and settings worth checking: Step 1: Disable Battery Saving Mode Go to: Battery Settings → Battery Saving → OFF When this is ON, the inverter intentionally draws a small amount of power from the grid to power inverter circuits This is often the main hidden source of continuous import. Step 2: Adjust Export Settings (If Import Persists) If Battery Saving is already OFF and you still see ~75W import: go to: Storage Mode → Allow Export: Enable Max Export Power: 100 Export Calibration: -100 These settings help “push” the system slightly toward export, effectively eliminating small residual imports caused by measurement offsets or inverter control tolerance.

But I have to mention But gotta say, I've seen Felicity batteries with better balancing, like my neighbor's one for example

@TaliaB @Steve87 Thanks for help Love the vibe here! Info's on point and the convos are lit 🔥. Appreciate the help!

@TaliaB I have charged it up to 100% and then slightly discharged it by exporting to the grid several times today. This led to a noticeable, though slight, improvement. At least this shows that the balancer is working. However, during the winter period, I didn’t allow it to charge to 100% very often.

So, do you think most LFP packs will perform similarly, but the absence of an active balancer here emphasizes the issue?

Hi, I’ve noticed a clear difference between generations. previous S5 unit was practically silent, even under load. However, with the S6, the noise is quite noticeable—I can hear it from about 10 meters away، I install it in my parents home and it starts to be annoying for them I did check the datasheet noise specifications, but I assumed that level would represent a worst-case scenario, not something I’d experience during normal operation. Now, with spring approaching and longer solar charging periods, the inverter runs under load for extended hours, and the noise becomes persistent and quite disturbing—especially during PV charging. Is this considered normal behavior for the S6 series? And are there any practical solutions or settings (e.g., fan control, firmware, installation adjustments) to reduce the noise?

@TaliaB The cells are well balanced and behave identically under high load, even near the lower end of their capacity. I’ve also verified this down to around 44.8V. The voltage delta only appears when the battery is at full charge, and it drops back within seconds once charging stops.

the same situation I have

55.9

Last update 26/03/2026 ( I managed to reduce the cell delta to 15 mv ,and the delta is still decreasing, by changing the requested chargeing voltage to 56 for 1 week and keep it balanceing ) I’m experiencing significant cell imbalance with my 48V 350Ah battery. The imbalance is most noticeable in the last seconds of charging, and the differences start to decrease once charging stops, even without discharging the battery. It seems that the battery’s built-in balancer is very slow, and charging stops when any single cell reaches 3.6V. Balancing only occurs during charging, which makes the problem worse. I tried keeping the charging voltage slightly lower to allow more time for balancing. I even disconnected the BMS cable and set a float charge around 58.8V. However, charging still stops when the battery reaches this voltage, so the balancing process halts as well. In other words, there’s no way to keep balancing active for several hours. One potential solution could be installing an active balancer, but opening the battery would void the warranty. Has anyone dealt with this issue? What would be the best way to improve cell balancing without risking the warranty? Thanks in advance.

💯 true It seems the parallel concept is sometimes misunderstood, and eliminating a single point of failure is underrated.

I have a simple question. When someone buys an inverter air conditioner, is the main reason to save electricity, or mainly to avoid the frequent compressor startups of a traditional AC? In other words, should we think of inverter AC primarily as an energy-saving technology, or as a way to eliminate on/off cycling and high starting current? I would be interested to hear opinions

Hey In some forums and discussions about photovoltaic systems, I have seen installers and users advising people to manually open the PV DC breaker (disconnect the solar panels from the inverter) when a thunderstorm approaches. The reasoning usually given is that the long DC cables between the PV array and the inverter can act like an antenna and may pick up electromagnetic pulses or induced surges from nearby lightning activity. According to this argument, disconnecting the array could reduce the possibility of a surge entering the inverter. However, I am personally skeptical about this idea. Lightning is capable of traveling through kilometers of air, so it is difficult for me to believe that a small air gap of a few centimeters inside an open DC breaker would meaningfully stop or block such energy if a strong surge actually occurs. From a physical standpoint, it seems unlikely that opening the breaker alone would provide real protection. At the same time, I have seen at least two installers who strongly recommend this practice during storms, claiming that it can help protect the inverter in some cases. Because of this conflicting advice, I am trying to understand whether there is any real technical basis for this recommendation or whether it is simply a precaution that people repeat without clear evidence. So I would really appreciate hearing the opinions and field experience of engineers, installers, and long-term PV system operators:

Can this feature make the 2 MPPTs work together for the same string ( load sharing)

That what I thought when I chose to install all on one MPPT I assumed that working around the nominal voltage (300 ish) would be better than ( 120) and more efficient

Hi everyone, I’m seeing a flat plateau in my PV production curve during peak hours (as shown in the chart from 2026-03-10), and I’m trying to understand the root cause. My system specs: ∙ Inverter: Felicity 5kW with dual MPPT inputs, each rated at 15A max ∙ Array: 7 panels × 580W = 4,060W total ∙ Measured voltage during plateau: ~300V ∙ Measured current: 11.2A – 11.8A Observations: ∙ Production ramps up normally in the morning, then hits a hard ceiling around 3,500W and stays flat for several hours instead of forming the expected bell curve ∙ pleaee ignore a noticeable dip and spike around 15:25 , it is because the battery almost full+ no load and grid was off ( so can’t export ) My questions: 1. Is this classic inverter clipping caused by the array’s power exceeding the inverter’s rated output? 2. Could the 15A per MPPT limit be the bottleneck here, even though my measured current is only ~11.8A? Any insights would be appreciated. Thanks!

Felicity T-REX 5 K inverter With Felicity FLB48100 battery My setup is Felicity T-REX 5 K inverter but with 16 kWh battery

it is winter now, so I am testing the worst scenario

Thant is the answer that I was looking for , thaaaaaaaaaank you 🤩. maybe operating near nominal voltage increase the MPPT efecincy and reduce thermal stress the looses wont be that much indeed !