0012

yes, that 3 stage method really is just a hangover from the lead acid era

You mentioned it was charged at high float voltage, what was the exact float voltage setting?

normal....

I think the answer is it depends. For me, I mostly interface with my system remotely, so it didn't make sense to get a local touch screen.

Is it cheaper to do say 15cell EVE batt with BMS 100Ah compared to just a pylontech 100Ah? Or is it more expensive, and if so, then what are the benefits to this DIY? Apologies if off topic.

Most definitely. There is a good chance that having the equipment (both the Victron kit and the batteries) installed by someone who is not an accredited installer will lead to the warranties not being honoured. Do not underestimate the value of a quality installation job. If you pay so much for the kit, don't try save cost on the installation and programming of it.

🤣

I don't know whether the 53.2V has anything to do with the swollen cells. However, it may be worth considering the 52.4V limit going forward? Even at 52.4V the SOC still reaches 100% on all batts.

Thanks. That is according to Pylontech's datasheet. Interestingly, Victron override this to 52.4V. When Victron detect it's a Pylontech connected, it automatically disregards the BMS's charge voltage limit of 53.2V and institutes its own limit of 52.4V https://www.victronenergy.com/live/battery_compatibility:pylontech_phantom

For interest, what was the Axpert voltage setpoint to charge the batteries to? Bulk/float charge voltage?

So mine is more like a complete system efficiency: 1442+6625-43=8024 6526/8024 = 81.33% So about 18.67% of my yearly energy (solar+grid) is just used to heat my garage 🤣 and most of that loss is the inverter/charger. Victron 10kVA Quattro, 250/100 MPPT, 4xUS3000 pylontech (3.5kWh each)

That looks so nice!!

It is dark and cloudy your side so that's why it stopped at 97% maybe. Anyway see how it goes. Definitely overnight with grid available the batt will just sit on 95% in status "idle"

Completely fine to opt for the "with BatteryLife" option, I just don't use it because I monitor often and don't let SOC stay that low. The result if used at 95% should be very similar to the "without BatteryLife" option anyway.

If you want the batts to go into idle... change the ESS to "optimized without batterylife" and set it to 95% unless grid fails. The batts will charge to 100% if there's enough solar, if there's not enough solar, they'll discharge to 95% and go into idle (taking power from grid direct to loads) unless grid fails then they'll start discharging further. This is what I did because I'm also not keen on the constant charge/discharge around 98-100% when in the Keep batteries charged mode. Mine is set at 85% now because we have consecutive overcast days with high chance of grid fault. But normally I set it to 25% and let the batts cycle down to that each night and minimise my power bill.

Awesome progress so far, enjoying this install!

Following and looking forward to the progress updates

Starting 1 Oct 2021 with 4x US3000 have now drained 2MWh from the batts

Oh dear, how old is the battery and how many cycles?

Is the battery possibly going into high voltage alarm? What is the max battery charge voltage? 52.5V is normally a safe setting for this

Some LEDs have horriffic power factor. Do a test at night. Switch all the lights off and compare W and VA readings. Switch on all the lights that are normally on, and compare W and VA readings again. That could possibly tell you whether you went too cheap on the LEDs A 5W LED bulb can draw as much as 40VA if it is cheap and nasty

https://www.victronenergy.com/solar-charge-controllers/bluesolar-pwm-charge-controller-lcd-usb Something like this, the charge controller can be programmed to disconnect load from the battery at 11.7V ?

Maybe what you're seeing is this... When the batt is over 90% full, the charge current limit set by the BMS comes down to 59.2A for 4xUS3000. From your screenshots, your batt was at 97% SOC.

Maybe only one batt's BMS is talking to the inverter, then the charge rate is limited to 37A for the US3000... who knows, more investigation required

And now, here is Feb: