Thatdamnjoe

Check section 3.1 in the coct sseg doc- they have a table for max sizes according to the size of your incoming breaker Why? Not sure but could take a guess Grading- If you somehow stuff up backfeed and feed back to minisub at more than what the incomer is graded for you could create a problem upstream.

Received some feedback from Sunsynk that it is "it is a contact that is normally open when grid is on and normally closes when grid falls away ", but nothing indicating that this functionality doesnt exist in the 12kW inverter. Assuming form their statement that it is a dry contact- Have not retested yet, but fairly certain it did not act as advertised when I last tested

According to the manual yes, but practically, it doesnt appear to work at all

Did you ever resolve this?

@Hitech Exact same issue - ever get it resolved? I made a post now and it was mentioned that the 12Kw sunsynk doesnt have an ATS240. Have sent query to poster @Steve87 for clarification

Hi @Steve87, Thanks I have sent a PM. That certainly would help explain why its not working as the manual suggests. It leaves some questions about the documentation quality of course.

Recently installed Sunsynk 3ph 12Kw inverter. Requested installer to use ATS240 to do neutral earth bonding. My understanding is that the inverters wets the connection and I should just connect a coil of an external relay to actually switch the E/N bridge. So if Eskom falls away I should measure 220V on the ATS terminals. However- if you read the function port definition it says the contact is a dry contact only. Problem is: It appears ATS240 is not switching correctly if Eskom falls away(yes, islanding mode tickbox is ticked). I can hear an internal sunsynk relay switch but nothing on the terminals. Tested for voltage (in case wet contact) and conneciton(in case dry contact) - neither seemed to work. Installer reckons "this a problem with all the 12Kw sunsynks he's installed- its a common issue" and I should just use an external relay linked to Eskom to do the bonding. This is the current setup - however, it is my understanding that this also means you dont follow NRS 097-2-1 Any thoughts how to address? Installer not making much headway in terms of clarifying this with Sunsynk as in his eyes the problem is resolved since the external relay using grid availability to make bond is acceptable. I said if the inverter isnt working we need to ask Sunsynk whats going on since its a brand new inverter-they should replace it if this one's ATS240 relay isnt working. From the myriad of posts both on this forum and elsewhere suggesting SUnsynk tech personnel are making recommendations to permanently bond E/N I dont have much faith that this will lead to a conclusion either. Thoughts? Appendix- sunsynk inverter manual showing ATS being wet contact Appendix- terminals showing dry contact

Came across this post and wanted to point out to @Kalahari Meerkat that you cannot assume the earth bond from the municipal side is always available even if power is off- cable theft is a reality in many areas. This is also the reason why you should not permanently bond your earth to neutral as you could unwittingly become the earth point for your entire neighborhood when the "permanent" bond at the municipal connection is stolen upstream.

This is correct, it shouldnt be earthed permanently. The sunsynk needs to connect earth to neutral only when eskom is down. Also, it sounds like a floating neutral problem for the 80V

Best I can figure from the Sunsynk datasheet it doesnt allow overspeccing to the same degree eg 15kw on the 10Kw inverter. Sunsynk goes to 13Kw on the 10Kw inverter, max input voltage of 800V vs the 1000V of the huawei. The big differentiator appears to be the passthrough performance of the sunsynk, I cant find any numbers for the huawei. Off-grid both deliver max Ac current around 15A ~16.9A, I dont know if thats per phase though, but I'm starting to guess it must be? Both are 10KW inverters, could this stat be per phase instead of in total? Huawei 10KW inverter looks like roughly ~R30k Sunsynk 10kw cant find a price immediately. but the 8KW is already around R40k so guessing around R50k 41-Sunsynk-10kw-12kw-Data-Sheet.pdf SUN2000-3-10KTL-M1.pdf

its 3-ph. Dont have the per phase breakdowns, probably the next step The Huawei comes in many flavours, but they definitely have Hybrids which work with Batteries. Here are some reviews/ I have also attached a datasheet. The off grid output specs of that datasheet is what concerns me as it appoears that in off-grid mode the 10kW inverter can only supply 3KVA, which would be odd indeed. I cant find another datasheet however so not sure if this is correct. I would prefer getting something thats going to find local support so the sunsynk is very much on my radar. Can one also "overspec" its PV side to the same extent as the Huaweis. Ie, install 15Kw of PV panels for the 10KW inverter, so even on overcast days one can get more power out of your system? Also curious if the sunsynk has a similar feature re: optimizers(see datasheet attached). My understanding is that these optimzers allow greater flexibility when placing Panels as it can in effect cancel out the effect of shade on one panel but still getting good output out of the string, like a local bypass for a shady panel if you will. SUN2000-3-10KTL-M1.pdf SUN2000-450W-P2 600W-P Datasheet.pdf

bump, any ideas?

Looking to install a fairly large hybrid system and need some advice. Firstly, The large system will be overkill, I dont use that much power but I also really dont want to run into cutouts due to hitting inverter limits, lots of breathing room then, but I am aware that means overpaying for largely unutilised capacity, i'm ok with that. Loads are all single phase- include Swimming pool pump Borehole pump 2 x geysers box freezer 3x fridges 1x freestanding freezer 4xtvs Washing machine dryer dishwasher 6x aircons, rarely used though ~80 downlights(mostly LED's) + 20 outside lights some underfloor heating almost never used Get a single large inverter (12kw/15kw) or rather parallel two smaller(8kwx2)? Not many options when you get to >10kW hybrids vs smaller sizes single unit is cheaper vs parraleled options Redundancy if one paralleled unit goes down extra wiring for paralleled more MPPT's so more string/layout options if paralleled Huawei 3-ph hybrids up to 12kw. sun2000-8-12 KTL M0 or M1 These inverters have pretty high efficency and it appears their capability to "over-install" on the PV side, ie put 20kw of panels for a 10kw inverter is appealing. as well as the neat integration with their LUNA batteries. Expecting some problems with shade so using their optimisers with some panels placed in different orientations or optimisers on the shady ones seems like a good fix. Are there other inverters that allow optimisers/overinstalling on the PV side? BUT Huawei inverters have the following on their datasheet which appears to show that when operating off-grid, (ie during loadshedding?), the output capability falls to 3300 VA? That would defeat the purpose of a large hybrid inverter for me during loadshedding so I'm confused by this limitation or I'm misreading it Had a goodwe ES some years back which didnt have similar constraints, ie 5KW on or off-grid as long as the loads were on the backup side as far as I recall Sunsynk inverters have an aux output which can act as a load dump, does nayone know if the huawei does similar, cant find anything on it? I see blue mountain energy 3ph inverters with local suppliers but cant find much online about these- is it a rebranded inverter from somewhere else? Any experience on these?

Curious, why did you say the property is on three phase power? If the incomer breaker isnt three phase? Or its terminating all three phases from outside but only connecting one of the phases to your loads?

Thats what I mean. If you have three phases available, then you try and balance across the phases. Some loads on the red, some on the white, some on the blue. Thats typical. You typically wouldnt max out the red before starting to load the white, although common sense isnt that common so anything is possible of course.