Mark R

Yes- primarily for two reasons. I installed solar to mitigate my carbon footprint, intending to use as little grid as possible. The inverter was incompatible with two US3000 Pylontech batteries - was only ever able to charge to a maximum of 32A. This led to prolonged charging times at the end of a battery cycle (which was mostly daily for half the year) during which time the inverter operated in line mode (with the panels only available for charging) until the SOC got to 60%, which was around midday. Plenty of morning grid use as a result. This despite an initially intact BMS-inverter connection. Had the firmware upgraded from China in about September, after which I completely lost the connection to the BMS and ran the system on voltages with worse efficiences. Learned a lot about solar generation during the year I had the system, and the sunsynk hits the spot. Except it is a hungrier voltage machine, so have come to the conclusion that I need to create a second string for the second MPPT which will need two more panels. Will have a go myself. Image attached describes the behaviour.

Chatted to installer who said that 3x360 panels runs the risk of not sustainably managing the start voltage and being 'kicked off' frequently. Would two more panels with a westerly orientation manage to avoid this? (I see start up voltage is 150V- are voltages for panels in series simply added together?)

Thanks for asking Tariq (and apologies to @Brani) - have confirmed with installer - all panels in a single series. (3 facing west, 6 North) Which makes me wonder about the shade effect of no sun. The installer joined the two strings into a single string because of the Sunsynk's greater voltage requirements. Have looked through my records and noted that the Growatt's best efforts at this time of the year were also just above 2kWh. Mark

Thank you for both replies. Don't completely understand the physics, but will take a stab at reasonable questions 1. Currently, isn't the West facing string of 3 panels in series being subjected to the minimum start voltage that the North facing panels are being subjected to by the MPPT by virtue of the two strings in parallel? If that is the case, is there anything to lose? 2. If the above is not the case, will adding them to a separate MPPT circuit result in a shorter more intense production day, rather than a more prolonged one (with the others), albeit in a less productive day in total? I am wary of more hardware (ie panels)- this is a rabbit hole whose bottom is proving illusory. Thanks again Mark

Dear All Would value your advice. Have upgraded from a Growatt to a Sunsynk 5kW Hybrid and all going well. Have two strings- the first, 6 x 360W panels in series facing North, and the second, 3x360W in series, facing west in Claremont, Cape Town. After installation of the Sunsynk, the second MPPT still remains unused. My production graph is attached. My roof pitch is approximately 22 degrees (and 16 deg Azimuth). On a sunny day like today, the total production from 3.2kW of panel was 9kWh. Peak production was at about 2kWh. Question- would I gain that much more out of my panels were I to connect the West facing panels to the second MPPT?

Beware.... <[email protected]> Mon, 19 Oct, 08:02 to me, 骆峰Martin Hi Mark， as we tried at noon，we have upgraded inverter BMS software to the newest version already， normally we suggest to install US2000 to work with inverter，US3000 isn't including in our supporting list，US3000 hasn't adjusted well enough yet，especially when two or more pieces US3000 work together，please kindly note， ---------------------------------------------- Any question, please do not hesitate to contact us. Yours sincerely, Mahone Wang | Africa Service W：+86 18668813227 W : www.ginverter.com Growatt New Energy Technology Co.,Ltd No.28 Guangming Road, Longteng Community, Shiyan, Bao'an District, Shenzhen, P.R.China.

What Growatt doesn't tell you at first. This after multiple tortured Teamviewer sessions with Mahone in China... (My system 3.2kW panel, 2xUS3000, and Growatt 5000TL-HVM Me Please Mahone Look at this that I have from April where you can see that my panels are locked in line mode until 60% SOC is reached after reaching full DOD. 1. Why line mode after DOD reached? 2. Why only 32A for charging as limit? (see attached pic of inverter behaviour- the 1650W flat line reflects the prolonged charging period at 32A. Only at 60% SOC are the panels 'released' to contribute to both load and charging) Mahone after many back and forths... 19 Oct 2020, 08:02 to me, 骆峰Martin Hi Mark， as we tried at noon，we have upgraded inverter BMS software to the newest version already， normally we suggest to install US2000 to work with inverter，US3000 isn't including in our supporting list，US3000 hasn't adjusted well enough yet，especially when two or more pieces US3000 work together，please kindly note， Summarised... Buyer beware. Mark

Have manage to update the Inverter firmware from Mahone, and can now drop the SOC to allow the panels to be 'released' by the BMS at a lower SOC. However still max 32A and what's worse is that SOC is read as 100% all the time. Inevitably total shutdown yesterday when batteries were truly emptied as they were never charged. Mahone in China says I need to update the BMS as well. Could you advise on how to do this? Do I update via the inverter or by plugging in directly to the battery Master? Thanks

And what makes just a little bit worse is that Manie from ICC software is not able support Growatt which would be a backdoor route to changing the inverter-BMS behaviour. Irritation value high, not sure if it warrants a new inverter or one of the more expensive versions. What is your way forward? Mark

I have a long running attempt to understand the relationship between my Pylontech BMS and the inverter settings. I have 2 x Pylontech US3000, the HVM inverter and 3.2 kW of panels. In the morning, particularly here in CT in winter, batteries get to to 22% DOD and from that point on, regardless of available panel charge, the BMS/Inverter will draw only 1650W until my lowest possible SOC of 60% is reached. At this point, suddenly the panels are then able to contribute to domestic load (see attached graphic). No attempt at changing settings is possible, beyond no. 12 being 22% and 13 being 60%. This particular event makes me circumspect about getting a third battery, as the charging time will become even longer should the DOD be reached. I am always able to get to full charge somewhere in the day (except on the darkest rainy day in the Cape) so this 'panel hijack' is deeply frustrating. Thoughts much appreciated.

Hello everyone Some questions and observations about the Shineserver app/web service. Do you have any idea how one would differentiate the daily/monthly contribution from PV directly to domestic load vs that to battery charging? Am finding the terminology in the glossary either very technical or lost in translation to English. I am trying to work out whether adding a 3rd Pylontech 3 kW battery would make any sense with the panel configuration (3.6 kW) I have. I have managed to fine tune the BMS/inverter settings to get to as little exclusive charging time as possible (DOD set to 22%, SOC up to 60%, only solar charge) to allow for as much panel contribution to domestic load. Rarely do I fail to complete 100% charging of the batteries although this winter in CPT has seen long wet periods. My ultimate aim is to use as little grid as possible which currently am unable to avoid after early hours of the morning until about midday. Many thanks Mark

Hello again. I have 9x360W Canadian Solar with 6 facing at about 16deg and the 3 facing just north of West. Live in Claremont. Then the Growatt SPF 5000 inverter with 2 x 3.5kW Pylontech batteries. Saw your thread about tripping. Had a trip this morning with very little else on when I put the tumble dryer. Error 07 (overload). System installed in Feb. Hope this doesn't recur. Mark

I am only surmising that from the steady current that the batteries seem to be drawing evidenced by the Table Mountain type shape of this on the image in my first post. During this time the household consumption is tracked almost exactly by grid supply until the batteries take over just before 12. This is the frustration, why can't the panels additionally supply the household needs when there is clearly capacity to do this in the middle of the day? As for new set up using your recommended settings, Cape Town just had it's first drizzly day in a long time and a late afternoon washing machine use has blown my best laid plans.

That is very helpful. Thank you. Interestingly, the SOC was locked at 95% when in exclusive solar charge for batteries (Sol in 14) but able to be manipulated once change to CSO. Looking good so far. Will post a picture of 24 hours of picture tomorrow. Still confused about why the draw from panels limited to 32A while in exclusive solar battery charging mode (Sol in 14). Any thoughts?

Hello I wonder if somebody could help me with the settings on my recently installed Growatt SPF 5000TL HVM 5kVA/5kW Hybrid Inverter with 2 x Pylontech US3000 batteries (and 3.2 kW of array)? I read with interest the topic initiated by @SiliconKid on the firmware update for the above combination. My intention to install SPV was not to beat loadshedding but to drop my CO2 footprint- i.e. use as little of the grid as possible. My problem stems from the way that I seem unable to harness battery and solar capacity to run household loads (washing machine etc) until the batteries are chargedto ~95%. I seem to have no control over the maximum current that the BMS imposes (32A, setting 11) nor do I seem to have the capacity for redundant solar charge to contribute to household load until battery charging is complete. The following might help to define: In the above, the ~ 9H00 surge in grid relates to when I changed the inverter from only solar to charge the batteries to both solar and utility (setting 14- SOL to SNU). 10H25 is the turning on of a borehole pump. Of course I could just buy an extra battery to allow for more capacity till the batteries are charged or schedule all loads till the afternoon - both options unreasonable! Is there any way that I could harness for household load the 1. Spare solar capacity (I have seen this approaching 3kW on a sunny day) or 2. Charge present in the batteries? I don't seem to be able to limit the Utility's supply to the battery which would potentially result in an early morning grid charged battery. I have DOD set at 25% and SbU for output source priority. Many thanks Mark