RobN

NE facing panels make more sense than NW facing panels, so I would have thought directly over the X. E facing panels catch the morning sun and start charging batteries early, when most needed; also more efficient as its cooler. My 2 pennies worth and also no expert in any way

Anyone know if the Deye and OHM (also made by Deye and appear identical) inverters share the same firmware?

They may discharge up to 50 W to supply the power needs of the inverter if the PV power capability is close to the Load requirement. If there is more than enough PV power, then the batteries' SOC stays at 100% with no discharge.

I'm not sure if this will make a difference; BUT if you have an "off-grid" system then "Prioritize Load" should be ticked in the work mode settings (next to Zero Export). In an "off-grid" setup, you typically want to power your load in preference to charging batteries, and only use surplus PV power to charge batteries. Your system is similar to mine, also running Solar Assistant and that's the way mine is set-up (but I have supported pylontech batteries). My 2 pennies worth.

Dear @zathras I am no expert, but here are my 2 pennies worth of comments. No experience with the panels you mentioned, but they have a high max current of >10 A. The Deye / Sunsynk inverters will only take a max of 18 A per MPPT, so you can only hookup 1 input per MPPT (each MPPT has 2 inputs). I have an OHM inverter (same as Deye / Sunsynk - all made by Deye and there are many other brands), but I have noticed that only Sunsynk has any form of support and/or regular upgrades, so would agree with you about going for the Sunsynk above the Deye. Good luck

@Leslie Just did a rough calculation on your setup and if the ambient temp is about 10 C, then your predicted max PV Voc will be about 580 V, which happens to be the maximum V the ESS Smile will handle. The solution, I think, is to split the array into 2 strings (6 panels in series) in parallel. This will halve the PV voltage, but double the Amperage which will have to be taken into account if you have fuses and cable sizing.

Hi @Leslie Are your 12 solar panels in a single string? If so, you may be exceeding the maximum Voc of the MPPT. The weather is colder at the moment and when the batteries are charged, there may be be a much lower load, resulting in the inverter limiting the MPPT and causing a rise in the PV voltage. This is worse if the PV cell temperature is cooler and might explain why you are only seeing it now. My 2 pennies worth. I'm no expert, so apologies if this sounds simplistic. Where are you based? Here in the Cape it's decidedly cooler and I have noticed an increase in my PV voltage, especially when the batteries are full and stop charging.

My solution to the Neutral-Earth bond in the OHM 8 kW inverter. Decided to mount the power relay inside the inverter, rather than in the DB (as suggested by @Vassen). Appears to be working well with no voltage potential between Neutral and Earth in either grid-tied or off-grid modes. Took the signal from the Grid input of the inverter. This version of the Deye / SunSynk / Ingwe / OHM / Sol-Ark / etc. etc., does not have the ATS 240 pins, nor the ability to upgrade the software (not anywhere I can find that is). This lack of obvious software support for the various models (all made by Deye apparently) is a strong indicator to opt for the SunSynk brand, as they do have an active support team and forum with a recent upgrade to the software that addresses this very issue. My 2 pennies worth. Thanks to @Halcyon and @Vassen for their suggestions and input. Keep safe

@Vassen, Neat! It might be the solution for me. Did you cable-tie the relay to the DIN rail? Although the OHM is supposedly identical to the SunSynk, it isn't and is more like the Sol-Ark sold in America. There are no ATS240 pins that I can see (see attached picture) and the software is of the Ingwe / Deye type, which I have not yet seen any support or upgrades for. Currently, I have a permanent Neutral-to-Earth bond in the inverter; as I feel that this is safer than a floating Neutral. I am 90% in "off-grid" mode and only need the relay when needing the grid during days of no / little sunshine. Thanks for the input, but it looks like I will need to take the signal from the grid. Keep safe and regards, Rob

The only difference that I can see, (there are some hardware differences with my OHM), between SunSynk and their brand clones is in the software interface. SunSynk uses the same software as Sol-Ark in the USA; whilst OHM, Ingwe and Deye use a different but similar and I think more intuitive interface. However, the SunSynk interface appears to be better supported and has had software upgrades with some improvements (including a software option to use the GEN signal for a Neutral-to-Earth bond relay when in "island" mode) and has an active forum on their website. I have not located such activity for the Deye, Ingwe or OHM brands. I have the OHM 8kW inverter and am very happy with the way it's performing, although mainly in off-grid mode (CoCT requirements if inverter exceeds 3,6 kW with a 60A main breaker).

Hello @Vassen, Interested to know how you got on with that relay from Communica? The suggestion by Halcyon is a neat solution, but I noted that the Axpert grounding box is only rated for 4,8 kW; so not sure how safe it is using it for my 8 kW OHM inverter. Regards, Rob

@Halcyon I have the OHM 8 kW inverter which I run mainly in off-grid mode, but occasionally need grid power to charge batteries when the weather is not co-operating. After reading about the issue of neutral - earth bonding, I tested my setup in off-grid mode and found V readings as follows L - N = 244, L - E = 50 and N - E =18 (On-grid it's L - N = 244, L - E = 230 and N - E = 1). Testing the E/L unit (button on the E/L) in the downstream DB, it trips as expected, both off-grid and on-grid. To me it appears I have the floating neutral problem and was wondering about how you connected the Axpert earthing box relay you mentioned to the inverter, and where did you get it? Regards, Rob

I have bought from ArtSolar on a number of occasions. Excellent service and very fast delivery, IF they have stock. My original deliveries were delayed because of the general Covid 19 lockdown, but that was hardly their fault. Delivery costs are calculated before checkout, so you can check. Strangely, you can save a fair amount in delivery charges if you order the panels in small batches (3 was the best in my case - came to about R540-00 for 3 panels delivered to Cape Town, 4 panels was double that. I think it goes on weight and if you exceed a certain weight then you are at the next level with an exponential increase in cost). Panels are working fine and delivering the expected power. I supported them as they are a local manufacturing company that actually produce a quality product. Only time will tell how they fare for longevity, but they provide a very decent guarantee / warranty.

Dear Forum, Slightly off topic, but a question of compliance (please move to more appropriate forum if required). Is it compliant if the earth leakage unit is wired unconventionally with the LINE from below and the LOAD to the circuit breakers from the top? The E / L is non-polar (does not stipulate a LOAD or LINE side) and is tripping as expected with earth faults. Browsing the internet, it appears not to be a problem (provided the unit does not stipulate a LINE / LOAD requirement); but would it be compliant and could a CoC be denied for this reason? Thanks for a great forum.

Halcyon, I read your other post in connection with your 5 kW Sunsynk inverter, but must admit that my setup has only just gone on-stream and I have not delved too deeply into the inverter settings yet. At the moment it is purely in UPS mode and appears to be functioning as such. The readings on the inverter appear to correspond to the usage meter I have connected (also an Effergy) Also OHM, although the same as a Sunsynk inverter, has a slightly different user interface and will require some puzzling out as I cannot find an OHM manual, only the Sunsynk one. Rob

Halcyon, Thanks for the reply. CoCT, in their wisdom and the way I understand it, won't allow the inverter AC grid feed to remain connected to the main supply, once the solar panels are installed. If the system is to be classed as "off grid", it has to be completely isolated. If there was a changeover switch, then the PV cells could be disconnected and the grid-feed reconnected on non-productive days and the system would revert back to being a UPS (it might require changing the inverter mode). I do not believe that my system will be permitted to operate in "Grid-tied with no feed-in" mode, as the inverter (on the CoCT approved list) exceeds their limitation (although neither the solar panels nor the batteries will initially be able to exceed 3,5 kW). I have a 60 A main breaker on the DB, although it appears that the supply point breaker is 80 A single phase; which implies either a 3,5 or 4,5 limit. I agree that "Grid-tied with no feed-in" would be first prize, and once operational I may well jump through the hoops to see if they will permit it; but in the meantime I am designing this as an "off grid" system. If you see any other way round the regulations, I would be pleased to hear them. Regards, Rob

Dear forum, I am new to the forum, but have been lurking for a while and have learnt a considerable amount. So, I have installed a UPS with a hybrid inverter (OHM aka SunSynk 8 kW) that is fed from my main distribution board and feeds to a sub board to supply most of the household. Currently only have a 3,5 kW/hr Pylontech Li-ion battery, but intend sourcing a second unit as soon as the current situation situation allows it. System is working, but not tested under load-shedding yet (temporarily suspended), but cannot use high-draw appliances (kettle) with the current limited battery storage. There is a manual changeover switch on the sub board (1 - 0 - 2) to bypass the UPS/inverter supply. The plan is to add PV panels soon and use those for charging the batteries instead of the grid as is the case now. To meet the City of Cape Town's regulations, I suspect that I need to keep the setup as "off-grid". My question: Is there a changeover switch available that will allow switching between PV panels (400 V DC) and grid (230 V AC) supply to the inverter? I foresee a situation in Winter, when there are a few cloudy/rainy days with no sunshine to recharge the batteries from solar, that I would need to use the grid to do so. I expect Eskom will continue to have load-shedding once this Corona virus lockout is lifted and industry will be playing catch-up. To be provocative, I have thought of a possible solution that may horrify the sparkies. Mount an appropriate AC isolator and a similar appropriate DC isolator side-by-side, but upside-down, on the DIN rail and then connect the handles with a connecting bar, obviously suitably labelled with warnings etc. Probably not a true "break before make" switch though. I suspect this would be non-compliant, but am interested in hearing the comments/outrage at this suggestion Thanks for a great forum, Keep safe, Rob N