WeNotGood

After some playing around, here is how the PV Master app works with "Economical Mode" under "Basic Setting" in the "Settings" menu, there is a distinct lack of documentation so I thought it may be handy. If there are any corrections please advise.
My big problem with the app is that there is no way to prevent the battery from discharging or charging under Economical Mode (as first priority) and have PV and Meter (only) supply Load.
As far as I know, there is no option to prevent the battery from discharging or charging as a first priority for example (1) PV => LOAD and (2) METER => LOAD, and to have the PV supply the Load (house). The app needs to be corrected to address this, the charge discharge menu is really non-intuitive and flawed. Rather a priority system should be used for the three power source INPUTS (meter, battery, and PV) and the three power OUTPUTS (load, battery, and meter) with an associated time schedule and power limits. This is a system seen elsewhere, unlike the methods Good We have adopted I have no idea why Good We resorted to such a complicated and clunky system. Example: For me after taking into account the total lifecycle of the battery and the initial purchase cost, the battery costs about 21.6c AUD per kWh to use, using the battery is not free, not for me, and not for you. Before 7am I can use off-peak power for around 15c per kWh. Solar is free (0c per kWh).
In this off-peak time I would rather have the battery neither charge or discharge, and have the PV reduce my load with the remainder from the Meter (grid) at 15c per kWh during off-peak. There is plenty of time for the battery to charge during the day from solar.
If I charge the battery during off peak this means a cost of 21.6c + 15c per kWh i.e. 36.6c per kWh, this makes no sense when the grid price can be less than that at some times.
In the end I am using Charge and 1% Rated Power meaning I am buying all of my power at 15c per kWh before 7am, with the PV charging the battery before that time. This is not optimal in the slightest as there are a few hours between sunrise and 7am where I am paying for the power I use, instead of getting it free from the solar panels. Note we have little to no export incentive where I live. ECONOMICAL MODE SETTINGS
A] Charge and 1% Rated Power (special)
METER => LOAD ~~Meter (grid) supplies 100% of Load (house) (PV => BATTERY) ~~100% of PV generation (PV solar panels), if any, charges Battery, excess (subject to limits or if battery is full) is exported to Meter (grid) if there is any. B] Discharge and 0% Rated Power (special)
(1) PV => LOAD ~~100% of PV generation (PV solar panels) supplies Load (house), excess is exported to Meter (grid) if there is any. (2) BATTERY => LOAD ~~If PV generation cannot cover Load (house), Battery supplies remaining shortfall. At night time this means the battery covers the entire load. (3) METER not used ~~Meter (grid) not used, unless battery State of Charge SOC is too low, then the grid covers the shortfall. C] Charge and 2% or greater Rated Power
METER => LOAD ~~Meter (grid) supplies 100% of Load (house) METER => BATTERY ~~The Meter (grid) charges the battery up to the Rated Power.  If your inverter is a 5kW inverter (5,000 Watts) and 10% rated power is selected, then the battery will be charged at 500 Watts. If the Load (house) is 900 Watts, this means a total of 1,400 Watts instantaneous power will be drawn from the grid (if no PV generation). (PV => BATTERY) ~~100% of PV generation (PV solar panels), if any, charges Battery, excess (subject to limits or if battery is full) reduces the load (if the PV cells are supplying 250 Watts, and the rated power is 10%, 500 Watts will be fed into the battery from the grid, for a total of 750 Watts). D] Discharge and 1% or greater Rated Power
(1) PV => LOAD ~~100% of PV generation (PV solar panels) supplies Load (house), excess is exported to Meter (grid) if there is any. (2) BATTERY => LOAD ~~If PV generation cannot cover Load (house), Battery supplies remaining shortfall only up to the rated power. If your inverter is a 5kW inverter (5,000 Watts) and 10% rated power is selected, then the battery (itself) will only cover an instantaneous load of up to 500 Watts roughly, the remainder will be covered by the Meter (grid). No power will be fed into the battery. (3) METER => LOAD ~~The meter will cover any shortfall, not first covered by the PV cells, or the battery up to the rated load. (if the PV cells are supplying 250 Watts, the Battery is supplying 500 Watts at 10% rated power, and the Load is 900 Watts, then the remaining 150 Watts will be taken from the Meter (grid). E] (Nothing selected)
Operates the same as Discharge and 0% Rated Power F] (Charge and 0% Rated Power)
Not selectable  

You could potentially do this with "smart" switches that will proportionally send power to the geyser(s) only once you start to export power to the grid, and only the amount that would of electricity that would have been exported otherwise, the below two products are available locally as far as I know, could be others also:
Solic200 - Single channel unit, no programmable timer
https://re-volt.co.za/Store/index.php?route=product/product&product_id=636
Apollo GEM - Dual channel unit wit a programmable timer, can also be fitted with a temp sensor.
https://www.apollosolarelectric.co.uk/products/ - Got mine from Rubicon in Cape Town, dealt with Nick Roche there
 
 

You could perhaps also generate a graphical report from SEMS from the time you are having issues, suggest start of with a wider date range, I also suspect SEMS is based on a time zone in Asia so you may have to select a time a few hours ahead for a recent event:
 

 
Make sure to select curve along with max 2 parameters (when generating a curve)

 
You can Zoom in and out of the area of interest using the sliders below:
 

 
 
 
 
 

You could perhaps also generate a graphical report from SEMS from the time you are having issues, suggest start of with a wider date range, I also suspect SEMS is based on a time zone in Asia so you may have to select a time a few hours ahead for a recent event:
 

 
Make sure to select curve along with max 2 parameters (when generating a curve)

 
You can Zoom in and out of the area of interest using the sliders below:
 

 
 
 
 
 

Thanks for the link, from the last report from the link:
The only two battery packs that made it through unscathed during phase 1 and are still going strong are:
Samsung Sony GNB PbA The only two battery packs that made it unscathed through phase 2 are:
GNB Li-ion Pylontech These large price tag batteries available also in SA, alas, did not manage to go all the way through phase two, which is worrying:
BYD LV - Suspected internal BMS failure of one battery module. BYD states all modules faulty due to cell imbalance Tesla PW2 - Battery not cycling as it cannot be externally controlled, but could have been a dud and was replaced, the replacement is still going strong. These once does not seem to like the higher temperatures, maybe best for the coast then:
Alpha ESS - Battery pack cycling affected by over temperature, Alpha removes its batteries  
The survivors from phase 1:

 
The survivors from phase 2

 
The Round Trip efficiency for the contestants

 
Hysterical laughter when you realised your overpriced, premium battery did not survive its phase and was outperformed by a battery that now cost 50% less!:
🤪😂
 

Hi @Bobster
I have noticed the same both with importing and exporting,
From observations the "leakage" seems to be a bit more pronounced when there are large loads switching on and off, e.g. our one 4kW geyser, and the larger the load the more the "leakage".
While most of the PV generated goes into charging the battery the "leakage is much lower if not zero, once the system start to export and the loads come online, the "leakage" seems to increase.
Purely a guess (without running tests), is that this is a way for the inverter to help balance and protect itself, rather than absorbing the surges (and compensating for short "dips") caused by especially the larger loads switching on and off and which will require extremely fast "reaction times", it uses the grid, while connected, as a bit of a buffer.
 
 
 
 
 

Quite an eye-opener. The article is a little out of date though, newer reports (Sept 2020) are available from the ITP site.

Thanks for the points mentioned:
1. The battery's warranty: as per data sheet it is a 5 year product warranty and a 10 year performance warranty. I am not sure exactly what this means, does this include the 8000 cycles quoted, and at what capacity level? Further research required.
Yes the warranty terms is expressed somewhat oddly and it would be worthwhile to clarify before jumping in and buying one.
2. It's a large "chunk" to buy in one go, and further expansion would probably mean another one of the same size (and cost). By contrast, the other options listed in the possibly outdated Goodwe datasheet (such as Pylontech) are smaller and thus easier on the pocket when expanding.
The price per kWh (~ R5000) is pretty good and kicking of with 10kWh capacity (at a similar price to what my 5 kWh modules cost just over 18 months ago) should be sufficient for most, sure the price will come down even more the next 12 -18 months should someone wish to expand.
In terms of Size, the narrower depth may even be an advantage for some installations
The Goodwe GW5048D-ES specs look quite strong and can handle a significant amount of PV (550V). Is it possible to put multiple units in parallel like the Sunsynk 5.5K?
Unfortunately the Goodwe does not Parallel, not to big an issue for myself and probably the majority of people who have one. The 4.6 kW Back Up output is a decent amount and with a bit of planning using appliances during load shedding it can easily support either using the Washing machine or Dishwasher or  Microwave / Kettle  during load-shedding (although not all a the same time 🙂 and the mix will need to be chosen carefully).
Another advantage of the 5048D-ES is the ability to charge at a decent 100A, while not the only 5kW Inverter able to do this, it is one of the few I have noticed withthe ability.
 

Interesting results out of Oz, not sure if Sony, Samsung is available in SA and how the prices compare with e.g. Pylontech
Would imagine that in terms of price vs. performance Pylontech must be the clear winner out of the below bunch, pity we do not have something similar for the batteries available in SA.
Top performers
Models that demonstrated superior performance:
The Sony and Pylontech battery packs have so far demonstrated superior capacity retention; that is, their claimed capacity didn't significantly diminish over time. The Sony, Samsung, Tesla Powerwall, BYD and Pylontech have shown high reliability. The Samsung and BYD have shown consistently high efficiency. This is a measure of how much of the energy put into the battery is actually stored and able to be extracted for use again. Most of the batteries have efficiencies around 85% but these two achieved about 95% efficiency. Added the price per kWh that i could find in brackets below
BYD B-Box < R8400 / kWh (not sure if the price is incl. VAT)
This battery has run without problems, and demonstrated high efficiency, though its capacity fade appears to be accelerating over time.
Pylontech US2000B < R5100 / kWh (not sure if the price incl. VAT)
This battery has had no problems in the test, and so far is showing very good capacity retention.
Samsung AIO10.8 - Available in SA?
This battery has proved very reliable and has had no operational issues. It's showing excellent efficiency so far. The battery is now sold under the brand name Hansol (a Samsung partner).
 
Sony Fortelion - Available in SA?
This battery has had no problems in the test, and so far is showing excellent reliability and capacity retention. Unfortunately, it appears to no longer be available in Australia.
Tesla Powerwall
This sample of the first-generation Tesla Powerwall has proved challenging to control for testing purposes, as it is not compatible with the SMA inverters used in the test lab. A Solar Edge inverter was used instead. While ITP is able to control the Powerwall to some extent, their only option was to have the Powerwall charge and discharge at its maximum rate, which is not ideal and may be accelerating its capacity fade. Nevertheless, so far this Powerwall has performed reliably and in line with its claims, with no operational problems. This model is superseded by the Powerwall 2.
Tesla Powerwall 2 < R10600 / kWh
Similar challenges were encountered as with the original Powerwall above. Also, a fault occurred with the first sample delivered to ITP; this was replaced by Tesla. The new sample has been on test since November 2018. There's not enough data to comment on its performance to date.
https://www.choice.com.au/home-improvement/energy-saving/solar/articles/solar-battery-trial

I have leds installed to indicate which circuits are live. As well all the switches have labels to indicate their functions.

😀 can imagine! Hopefully it was lead-less solder wire!

Agree, very nice install, also like the additional "heatsink" idea on the SmartSolar 250/100 MPPT.
Perhaps a silly question, but why the two DC fuse boxes used  with 5 kVA inverter?

Ah. That's an Axpert VM III. Equivalent to the PIP-5048GK, as you can see from this handy post. Sorry, I had confused the models also; I should have checked that post myself. I've not heard of that brand, so you might want to check out my Do I Own a Clone post.
Oh. That should be plenty. And Voc is only 360 V @ 25°C, some 385 V @ 0°C. So it's not shutting down through over-voltage.
That's quite strange. I don't think it's like the dips others have been seeing. [ Edit: I know that the linked post refers to a completely different model, but many of the non-MK models seem to be exhibiting these dips and freezes. ] For example, the period around 8am here:

Note how the PV volts stays high, as you'd expect from no load. Yours shoots down to 120 V, which happens to be the minimum MPPT voltage. It's as if the panels have gone high resistance, such that the slightest load from the MPPT, which presumably starts at 120 V, causes the voltage to collapse. So the MPPT keeps the current very low to prevent that voltage collapse, achieving a maximum power point that is so low it reads a zero.
That suggests a panel fault (some sort of intermittent high resistance connection or diode). If you used eight of those panels for the PIP-5048MS test, perhaps one string went open circuit, and you would not notice because the other string still produced. It would be good to test the nine panels in series on another string inverter, if possible.
How about their performance in shaded conditions (as opposed to cloud, i.e. some solar cells in good sun, others in shade). I can imagine an open circuit diode causing production to plummet in shady conditions. However, you seemed to be talking about a uniform grey sky. There could be an unusual problem with cabling, connectors, fuses, etc.
Unfortunately, firmware update files are very hard to come by these days. There was an Axpert VM III firmware published here, but it's for a fairly old firmware version (20.59). No patched firmware is available for this model.
[ Edit: 5058 → 5048. Sigh. ]

You could perhaps order one of these "electric showers" from the UK 🙂 They heat as you use the water. Not sure if they are available in SA.
https://www.screwfix.com/c/bathrooms-kitchens/showers/cat820272
But then again if you can heat the geyser with excess produced renewable electricity (if you produce excess energy) then it acts as as a "store" of energy and the hot water is pretty much free.
 

The reason for the two element geysers, in the UK at least is that you have the option to get "Economy 7" supply when the electricity is cheaper from midnight to 06:00 or 07:00 in the morning, during the day the top geyser element will switch on according to the thermostat setting, heating only a little amount of water, due to stratification, during the cheaper tariff the bottom element will be switched on, and heat a larger volume of water,  and that is also why they are vertical. This option is mostly when you have an electricity only energy supply.
https://en.wikipedia.org/wiki/Economy_7
The geyser @Vasan has shown is used when you also have a gas supply and uses a gas boiler for water / room heating, the electrical element is mostly for backup as the price for gas in the UK per kWh equivalent is far less that electricity per kWh and probably now also less than we pay per kWh for electricity in SA, last time I checked it was around 5 pence per kWh equivalent i.e. ~ R1.10. also depending on supplier as you can actually choose from a number of suppliers.
https://powerforum.co.za/topic/5431-geysers-with-two-elements-in-south-africa/?do=findComment&comment=83693
So much then for Eskom argument of our Electricity being relatively cheap, when you can get cheaper energy using gas in Europe.
 

The reason for the two element geysers, in the UK at least is that you have the option to get "Economy 7" supply when the electricity is cheaper from midnight to 06:00 or 07:00 in the morning, during the day the top geyser element will switch on according to the thermostat setting, heating only a little amount of water, due to stratification, during the cheaper tariff the bottom element will be switched on, and heat a larger volume of water,  and that is also why they are vertical. This option is mostly when you have an electricity only energy supply.
https://en.wikipedia.org/wiki/Economy_7
The geyser @Vasan has shown is used when you also have a gas supply and uses a gas boiler for water / room heating, the electrical element is mostly for backup as the price for gas in the UK per kWh equivalent is far less that electricity per kWh and probably now also less than we pay per kWh for electricity in SA, last time I checked it was around 5 pence per kWh equivalent i.e. ~ R1.10. also depending on supplier as you can actually choose from a number of suppliers.
https://powerforum.co.za/topic/5431-geysers-with-two-elements-in-south-africa/?do=findComment&comment=83693
So much then for Eskom argument of our Electricity being relatively cheap, when you can get cheaper energy using gas in Europe.
 

Or you could monitor the flow between the UK and other European countries, if you wished:
https://extranet.nationalgrid.com/RealTime
Makes you wonder why we are so limited just trying to contribute to the local grid!

Also looked at their system with the PTC element for the second Geyser (which is in a flat, attached to the house we rent out).
We have the Geyserwise Delta T, with the circulation pump, which is another pain during load shedding as the pump did not work during loadshedding.
The advantage of the Apollo GEM and similar is that you can really get the maximum out of your system in term of self use, before we had the Apollo GEM our self use was around 50% during summer and 70-80% during winter, now it is >90% during winter and expect it to be >70% during the summer.
From other people's replies re CoCT, they do ironically seem to be more of a hindrance than a help, especially with getting people weaned of Escom but then again it is probably in their own interest to restrict people as much as possible when it comes to renewable energy.
With the limits CoCT impose it may be difficult to fully optimise a system, but CoCt restrictions aside, knowing what I do now,  I would not consider a Geyserwise again but rather increase the capacity of the PV system with a Apollo GEM or equivalent and/or add battery storage with the Geyserwise money or even another Geyser in series to be heated with the excess energy.

You could also use a device that send power, that will otherwise be exported, to the Geyser(s).
We have installed an Apollo GEM with two geysers connected and it has diverted over 1 MWh of energy to the Geysers in just over 6 months, keeping in mind this covered the winter period.
Another option is the Solic 200 which looks like a very robust unit, but only has one channel. It also does not have a timer function, but rather a manual "boost" function.
 
 
 
 

While shopping around I noticed the Solis inverters one of the very very few that appear on COCT's infamous list with NRS-097-2017 certification.
This got me interested in the 15KW three phase model which seems OK on paper and remarkably affordable.
I have a question that appears to be partially answered by going carefully through their installation manual.
I would need to control the power during an islanding situation with the inverter connected to the output of a victron Multiplus - the latter configured to be a simple UPS, excess power from the Solis fed to the grid (if available) through the inverters transfer switch.
During grid fail the transfer switch is open and the Victron inverter does its UPS thing. This allows the Solis grid tie to continue operating. However power needs to be throttled to that required by any loads. The Victron, fitted with the PV assistant, uses frequency shifting to control a grid tie at its output (typically between 51 and 53 Hz with 53 Hz being "off"). Excess power during load dumps is simply shunted into the battery. 
So, anybody used the "Freq Derate" option selectable in the Solis setup ? It appears you can set the min/max frequency for control but the manual is a bit thin in this regard. Anybody have such a grid tie and in familiar with the settings ? Anybody have a contact to somebody knowledgeable perhaps  - not to importers that just move boxes please.