Hagu13

OK after reading Sarel's thread and the other comments I think I should have given more info
Although the new system will be at a new house it's the same family so a lot will be the same.
We're light on juice. We consume about 300kWh per month total. More in summer as we pump water for irrigation and sometimes use AC. But there's always excess generation for this. Water heating is solar supplemented by gas, cooking is gas, space heating with wood. New appliances selected for energy efficiency, LED lighting, etc.
We don't select essential or non essential loads. The jacuzzi is on a changeover switch so we have the ability to run it direct from grid when we want to run the 4kW element. The daily filter cycle is run on the solar though.
The whole house is on the 5kVa Axpert. We typically don't have throughput issues and we're used to shifting loads around, but more size here would mean less management of the females in the house which can be akin to herding cats at times
We have a grid connection, don't want to backfeed, just want reliable electricity and low bills. We get the battery full around lunch time for 8 months of the year so beyond the point of diminishing ROI with more panels. But I'm not dead against more and would like the capacity for it in case I get bored or have money burning a hole in my pocket.
We run on batteries at night and usually make it, except in winter when we're not getting them to 100% before sunset, or when the girls insist on doing an oven cooked supper after the sun has gone. 50% more battery would resolve those issues.
So I really have enough but more would make things go a little smoother and require less tweaking and management. From that perspective as well I have one of those dinosaur Axperts and needed to buy a RPi and ICC to make it less dumb and more Pylontech compatible. Where are we on the newer inverters in this regard? Do I still need the same add on or can the inverters talk to apps and IOT devices directly?
 
 
 
 

Most new inverters comes with a wifi dongle and you can monitor everything via an app but the apps can't switch loads on and off yet.

THanks all
 
Plenty to research now but please keep the suggestions rolling in
 
as 87 Dream put it, I don't want to make a less than optimal decision out of ignorance. I could slap in a new Axpert which has bigger MPPT than my existing one and some extra panels and 3 Pylons this time and I'll be ok. But there's scope to do better things and functionality I haven't even considered, so this is all great at targeting my reading from here.

I can only show you a photo or two of the bloudraad en tang affair we temporarily put up here, as for moving it, I'm doing this by hand at the moment, long term I'll be looking at a larger structure where I'd have all panels swinging back and forth and driven by a worm gearbox with, possibly an Arduino as the controller and with some near realtime clock data to determine the best angle, I don't care about getting maximum smoke down to the last watt out of the panels, as long as I'm getting within 200W of what it can achieve, I'm fairly happy. (One can mount a sensor and follow the sun, but I reckon, waking up every 10 or 15minutes and moving the array onwards a little bit, would be more than perfect, since right now, doing this manually, I have them east, by 9-ish I move them, again by 12-ish lay them flat, by 1400-ish I point them 45 degree to the west and by 1600-ish make them face west and it works fairly well.)
I'm attaching two photos that show the panels to the east, just before I turn them to app. 45degree up to the east and then after I turned them, the 9 panels to the left in a row of the 4 and 4 rotatable ones, are fixed app. North.
The attached power curves was for yesterday the red line, obviously being the panels that change orientation and the blue cuve are the 9 fixed panels, at peak the 9 panels produced app. 2k2W and the 8 panels just shy of 2kW, 1971W to be exact. Either way, if you look at how much earlier and how much later the 8 panels make electrons run around the cables, it seems like more for less, but one would have to put up a somewhat sizeable structural marvel to ensure that winds & all don't cause any grief.

I currently have all 6 facing north but I've looked into east west arrays and I like the idea. Very likely I'll be pointing the existing panels east and the new ones west, and I'll be very slightly over the 3kw rating, perhaps not in that layout

Just a thought, the panels lose efficiency after about 3-5years and drop by around 5-10% anyway, so get panels that wont exceed your VOC, 335w or similar,try to keep each string the same, and add to existing array.
Alternatively if you had multiple arrays pointing say east and west, one could use existing panels to carefully oversize an array, position the panels in such a way that enough get direct sunlight say in the morning, the oversized portion getting less light, and it swops around in the afternoon, that way it will give a you a more flat peak on your PV curve, you will generate on one array for more hours, and not exceed your MPPT limits? It will depend on your system  configuration, and may need some experimentation.

These
https://www.solar-shop.co.za/canadian-solar-panels/80-canadian-solar-305w-poly-kupower-half-cell.html
may be an option and may not be too far off your existing ones...

I think there is a line that one should not cross. AIUI the batteries take a knock if run down to less than  (about) 10% SOC. 

Hagu13, I think you are set up nicely and as you said when there is loadshedding, you can plan for that with the needed SOC
Unfortunately for us here in rural Limpopo, infrastructure maintenance is a huge problem so it's almost always a gamble with how deep you discharge your batteries as one storm, one gust of wind, one fart in the wrong direction can mean anything from 1 to 24 hours without grid, and this happens a lot.
So I run my batteries from 2am (can probably start at midnight rather), then wait for PV to start up after 6am, charge batteries during the day, which is usually done around mid day on a good day, then we add load as needed to maximize PV and switch back to grid around 5pm.
I can extend my night hours on the batteries, but then we have no backup should something go wrong and there is a rainy day or two. Here in the Lowveld it gets seriously overcast some days, we had two weeks now with very little sunshine and lots of rain, but we do not complain as we are coming from a severe drought. Unfortunately it is under these conditions (wet/damp) that we experience most of the grid cable faults, potentially leaving you without grid for a long time.
All this said, it basically just comes down to different circumstances, there is no one correct answer for everyone and it seems you understand your needs and risks well and plan/run your system accordingly

There was 'n long discussion on this a few weeks back. Best to do a search, but I think is was @phil.g00 who has good background in doing this

This depends on the specification of your inverter. For your 145V model that is the very max, and you should stay with around 118V as max. This means 2 panels in series and not 3. So I would not change this setup if I were you. 
If you do go with 3s, you might actually have more losses as you are using the same cable for more current than with 2s. With 2s you just have more cables spreading the load. 
This is true, but in practice does not make that big a difference. You will see that as soon as the sun hits the panels it will just to it's preferred voltage. It is just the current that is low. So having the sun hit the panel at more of a right angle will give you more current, and that is what you want. Adding panels that catch the very early morning rays at a right angle (close to 90deg) will give you more current than rays at a very small angle (10deg). So I will say add panels east and west. 

I would have thought that these two would have been exactly the same.
But the effect is the same: self consumption comes from the battery, thanks to the lack of an AC power supply since models manufactured about 2014.

The Axpert draws its self-consumption always from the battery - even if it is running in utility mode. So yes, this is perfectly normal in your case

I'm new to the forum but I've been getting sent here by Google more and more so it was time.
Very interested in giving less money to Eskom (my employer, for my sins) and started automating and tweaking more and more in lockdown as I'm working from home. Where I'm at at the moment:
Water heating by 2 solar flat panels with 150l geysers in series (professionally installed) with a 5l/min gas geyser downstream when needed (self installed) Currently manually controlled but automation is in its future.
Electrically I'm on a 5kVA Axpert (whole house except jacuzzi) with 2kW of solar and a 3.5kWh Pylontech, watched over by an ICC Pi. All self installed about 5 years back. I'm new to the Pylontech and ICC. One day when I'm big I'll get another battery and more panels and stay off grid at night.
Downstream of that I've been playing with a multitude (mess) of cheap Chinese smart bulbs, Sonoffs for other lighting and jacuzzi control, Sansui smart plugs to make the coffee and a Broadlink RM Pro for the AV stuff and ceiling fans. Loosely and unreliably bound together by Google home. I can still more or less understand this lot so I'll doubtless be complicating it further soon.
Future plans include integrating the ICC into the automation. in fact automating and linking everything that will stand still long enough. And more solar and batteries, and world peace.
 

Comms are reestablished and Riaan is as efficient and pleasant as I'm used to. 
Great guys to deal with.
 

Comms are reestablished and Riaan is as efficient and pleasant as I'm used to. 
Great guys to deal with.
 

I will respond to the last mail received from you now, I have checked spam etc, and cannot find anything more than that. I drive around with your cable in my vehicle, and admittedly, it has quite a couple of km's on it at the moment 🙃

Give HomeAssistant a try, if you haven't already. It makes controlling and automations all the smart devices much easier. I have ICC sending data to my HomeAssistant to then automate stuff based on PV production and inverter mode etc. 

I'm new to the forum but I've been getting sent here by Google more and more so it was time.
Very interested in giving less money to Eskom (my employer, for my sins) and started automating and tweaking more and more in lockdown as I'm working from home. Where I'm at at the moment:
Water heating by 2 solar flat panels with 150l geysers in series (professionally installed) with a 5l/min gas geyser downstream when needed (self installed) Currently manually controlled but automation is in its future.
Electrically I'm on a 5kVA Axpert (whole house except jacuzzi) with 2kW of solar and a 3.5kWh Pylontech, watched over by an ICC Pi. All self installed about 5 years back. I'm new to the Pylontech and ICC. One day when I'm big I'll get another battery and more panels and stay off grid at night.
Downstream of that I've been playing with a multitude (mess) of cheap Chinese smart bulbs, Sonoffs for other lighting and jacuzzi control, Sansui smart plugs to make the coffee and a Broadlink RM Pro for the AV stuff and ceiling fans. Loosely and unreliably bound together by Google home. I can still more or less understand this lot so I'll doubtless be complicating it further soon.
Future plans include integrating the ICC into the automation. in fact automating and linking everything that will stand still long enough. And more solar and batteries, and world peace.