Choosing the title here was a bit difficult, so just went with my feeling currently.

So I am currently sitting with the Solis S6 6kw, which are relatively cheap these days, and with (2 x (7 x Jinko 555w)) dolar panels. This has worked flawlessly over the last few years.

Fast forward to now, we are looking to purchase property, and the one we might buy has a victron system.

Multiplus 2 5kw

6 x 600w panels

Here is where the issue comes. Should I stay with solis, and add another 6kw, or sell the solis, and move over to victron?

When I started searching for an MPPT that would support my current array, the only viable option is the 450/200, these things cost 32K, only support 4kw per tracker, and a max output of 11kw 😂

To use the victron, I would have to get anoter multiplus and the 450/200 total cost of R48K, I could just add 3 more S6 S6kw, have a total of 24kw, and 38kw of solar, and 8 trackers)

I just feel that I am missing something crucial here.

33 minutes ago, Pho3niX90 said:

I just feel that I am missing something crucial here.

yes, well, there is no reason to throw everything at one MPPT... you could for instance consider doing 3 MPPT's, 2 X 250/100's (6S1P panels each, assuming the Voc fits) and one to suit the remaining 2 panels, there is more than one road that lead to Rome...

I also was of a similar feeling, specially since Victron was very expensive back in 2020/2021, but since their pricing has come down quite a bit and unlike your all in one outer-Mongolian units, are fairly EMI/RFI quiet, as opposed a lot of the all-in-ones/high frequency inverters.

Looking at just one MPPT does not make sense... lightning strike and the MPPT is gone... no panels will produce power, whereas if your panels are slightly spread out and running on 2 or more MPPTs, then you may at least still have some solar power being produced, if weather has struck...

Just because your 14 panels in a single string may fit the 450/200 (not sure, maybe its 7S2P), does not mean that this is the correct way to implement the solar power production side...

Here, FYI, I was running a 5k SunSynk, now I have 3 X Multiplus II 3000VA's in parallel and 2 X 250/100 MPPT's + 1 X 250/85 MPPT and a bunch of batteries... off Eksdom's infrastructure, of course.

Edited January 25Jan 25 by Kalahari Meerkat
assuming...

24 minutes ago, Kalahari Meerkat said:

yes, well, there is no reason to throw everything at one MPPT... you could for instance consider doing 3 MPPT's, 2 X 250/100's (6S1P panels each, assuming the Voc fits) and one to suit the remaining 2 panels, there is more than one road that lead to Rome...

I also was of a similar feeling, specially since Victron was very expensive back in 2020/2021, but since their pricing has come down quite a bit and unlike your all in one outer-Mongolian units, are fairly EMI/RFI quiet, as opposed a lot of the all-in-ones/high frequency inverters.

Looking at just one MPPT does not make sense... lightning strike and the MPPT is gone... no panels will produce power, whereas if your panels are slightly spread out and running on 2 or more MPPTs, then you may at least still have some solar power being produced, if weather has struck...

Just because your 14 panels in a single string may fit the 450/200 (not sure, maybe its 7S2P), does not mean that this is the correct way to implement the solar power production side...

Here, FYI, I was running a 5k SunSynk, now I have 3 X Multiplus II 3000VA's in parallel and 2 X 250/100 MPPT's + 1 X 250/85 MPPT and a bunch of batteries... off Eksdom's infrastructure, of course.

I do like the fact that it's modular. I suppose my fears come down to spending roughly 20-40K just to get the same performance I am currently getting.

One thing I also noticed is th TR vs MC4, is one better than the other in your opinion?

From my current stats, my one string (7 x 555w) produces 255v @ 15.8a, and I cannot seem to find specs that indicate if the 250v is a hard limit on those trackers, that is the only reason I went a step up to 450.

Then again 7 panels in series X ~50V (Voc) = 350V, so max 5 panels on a 250/100?

Edited January 25Jan 25 by Pho3niX90

13 minutes ago, Pho3niX90 said:

One thing I also noticed is th TR vs MC4, is one better than the other in your opinion?

I did not go the MC4 route, since that would require more plugs yet again... since the wiring comes from a circuit breaker, which does not use the MC4 connectors, I have stripped wire ends (without bootlace ferrules) going to the MPPTs and on the CBs end.

15 minutes ago, Pho3niX90 said:

Then again 7 panels in series X ~50V (Voc) = 350V, so max 5 panels on a 250/100?

Ideally we'd need to check your panels' specs, I just thumbsucked the number to make the point that all eggs in one basket is not the correct option, in my opinion.

If these are your panels, then 49.62Voc seems to be the number, call it 50V, so a maximum of 5 panels in series on the 250/whatever MPPT would be ok, I'd think. Now if you did 5S2P, then you'd come close to maxing out the 250/100, so one of those and another smaller one for the remaining panels or get some more panels and fill up another 250/100 for 10kWp MPPT/solar power...

Edited January 25Jan 25 by Kalahari Meerkat
route not router... fat fingers...

21 minutes ago, Pho3niX90 said:

I do like the fact that it's modular. I suppose my fears come down to spending roughly 20-40K just to get the same performance I am currently getting.

That has been my leaning as well, if one MPPT packs up it doesn't affect the others or the inverter etc. so a more redundant setup, sure, more individual components, but the same as with batteries, you have similar to my setup some home-brew EVE 300-odd Ah based batteries, if one goes south, BMS or one or more cells/whatever, you are not off, but inconvenienced and you can sort it out, without being without electricity...

Something else to consider - I have a Sunsynk 12kW single phase inverter that I installed in September 2024. This has been running quite well, but it has one "problem" (actually designed like that by Sunsynk) that has been frustrating me since soon after I bought it - it deliberately uses the grid as a buffer to even out short-term peaks and lows.

Even with full sunlight capable of supplying more than double the currently consumed load, whenever an additional (smallish) load is switched on, the unit will draw some of that load from the battery, and the majority from the grid, until the MPPTs have "latched on" and "stabilised" - doing this for a number of minutes whilst slowly ramping up the solar power until it carries the full new load - and wasting my money in the process. After going "off grid" some months ago, I noticed that the Sunsynk now happily use the batteries as a buffer (as it does not have a grid buffer to use any more...) under the same conditions where it had previously used the grid - so it is quite capable of adjusting to new loads by only using the batteries as a short-term buffer... so why use the grid (when available) as it's primary buffer?

A colleague of mine installed a slightly smaller Victron unit soon after I installed my Sunsynk, and his unit uses only the batteries as a short-term buffer, and only switches to Grid when the new load is so large that the batteries cannot cope. It is thus quite clear to me that the two manufacturers have widely differing philosophies (as could be expected, I suppose...), with Sunsynk figuratively saying "screw the customer's money, let's limit our risks as much as possible by always using the grid when the load changes", whilst Victron says "the customer has sufficient battery capacity for most changes in consumption, let's not waste his money by using the grid unless really necessary".

Now, given that my gripe is not sufficient reason to return the Sunsynk for a refund and buy a Victron, I would just have had to live with it if I did not by happy coincidence find a simple and free work-around by simply switching off my grid. So, ask yourself which of the above mentioned philosophies would you prefer?

15 minutes ago, HennieL said:

Something else to consider - I have a Sunsynk 12kW single phase inverter that I installed in September 2024. This has been running quite well, but it has one "problem" (actually designed like that by Sunsynk) that has been frustrating me since soon after I bought it - it deliberately uses the grid as a buffer to even out short-term peaks and lows.

Even with full sunlight capable of supplying more than double the currently consumed load, whenever an additional (smallish) load is switched on, the unit will draw some of that load from the battery, and the majority from the grid, until the MPPTs have "latched on" and "stabilised" - doing this for a number of minutes whilst slowly ramping up the solar power until it carries the full new load - and wasting my money in the process. After going "off grid" some months ago, I noticed that the Sunsynk now happily use the batteries as a buffer (as it does not have a grid buffer to use any more...) under the same conditions where it had previously used the grid - so it is quite capable of adjusting to new loads by only using the batteries as a short-term buffer... so why use the grid (when available) as it's primary buffer?

A colleague of mine installed a slightly smaller Victron unit soon after I installed my Sunsynk, and his unit uses only the batteries as a short-term buffer, and only switches to Grid when the new load is so large that the batteries cannot cope. It is thus quite clear to me that the two manufacturers have widely differing philosophies (as could be expected, I suppose...), with Sunsynk figuratively saying "screw the customer's money, let's limit our risks as much as possible by always using the grid when the load changes", whilst Victron says "the customer has sufficient battery capacity for most changes in consumption, let's not waste his money by using the grid unless really necessary".

Now, given that my gripe is not sufficient reason to return the Sunsynk for a refund and buy a Victron, I would just have had to live with it if I did not by happy coincidence find a simple and free work-around by simply switching off my grid. So, ask yourself which of the above mentioned philosophies would you prefer?

The issue you mention is present in the Solis brand as well. It's just a hard pill to swallow for the price difference. I have however decided to go with Victron, as it should be cheaper in the long run to expand only the specific areas as needed.

16 hours ago, HennieL said:

Even with full sunlight capable of supplying more than double the currently consumed load, whenever an additional (smallish) load is switched on, the unit will draw some of that load from the battery, and the majority from the grid, until the MPPTs have "latched on" and "stabilised" - doing this for a number of minutes whilst slowly ramping up the solar power until it carries the full new load - and wasting my money in the process. After going "off grid" some months ago, I noticed that the Sunsynk now happily use the batteries as a buffer (as it does not have a grid buffer to use any more...) under the same conditions where it had previously used the grid - so it is quite capable of adjusting to new loads by only using the batteries as a short-term buffer... so why use the grid (when available) as it's primary buffer?

This is interesting. My Goodwe works in a similar way to the Sunsynk. The way to get the best performance out of my inverter is to set it into off-grid mode. Pro: It now only deals with PV and battery. Con: Non-essentials now powered by grid (unless I switch off the main breaker, in which case they don't get any power at all)

Edited February 14Feb 14 by Bobster.

3 hours ago, Bobster. said:

Con: Non-essentials now powered by grid (unless I switch off the main breaker, in which case they don't get any power at all)

Fortunately, my system is large enough (12kW inverter, 20kWh batteries) that I could couple all my load (apart from the geyser) to the "UPS" outlet. On the positive side, the Sunsynk inverter also has a third "Auxiliary" port that can either be an input from (say) a generator, or a controlled outlet that is controlled by the battery SOC and the availability of sufficient solar power - and my geyser is connected to this Aux port (so that the geyser will operate normally from either solar or battery power, as long as the battery is above a set limit, and the PV input is also above a set limit).

I would still have chosen to go with a Victron (even at greater expense...), had I known about this "unnecessary grid using" issue when I installed my system - unfortunately only hindsight is 20:20, but this discussion can hopefully serve as a warning to new potential solar owners to think twice before buying the cheapest Chinese designed and manufactured brands...

It turns out, the house has a multiplus 1, and because it's a gen 1, the price is almost double. Therefore, the victron system makes no sense for me, I would rather replace the entire all in one inverter (solis) when something fails inside, for less money, than an MPPT or even a multiplus.

1 x 6kw solis cost max R19K

1 x 450/200 (11kw charge max) MPPT averages around 30K
1 x Multiplus Gen 1 averages around 20K (if you can find them)

Edited March 3Mar 3 by Pho3niX90