Stranger

OK so a lot of water has run into the sea in the past few weeks.  I've gotten quotes upon quotes and finally got bank approval on a loan for both the property and a solar system.  The solar system's allowed price is, for all intents and purposes, R200,000.  That would include a generator connection, but not the generator, I have that already.  It it strong enough to produce twice my load easily, and around 3-4 times the load of my entire house when it's idling.  In other words, if I'm not running high current appliances like the stove or geyser, the generator can run my entire house's usage 3 to 4 times over, maybe even more, with regular use (water pumps, lights, fans, computer and internet access, TVs, etc).
What I planned on getting is the following:
1 x 8kW inverter.  Right now Deye looks to be the most promising, although Sunsynk seems to be a bit cheaper for some reason on my quotes.  I prefer the Deye software though, and Sunsynk's app looks like it's offline a lot these days.
4 x 5.12kWh batteries.  I planned on Deyness for the 10 year warranty, but I can get 2 x 10kWh from Sunsynk with the inverter for the same warranty as well.  I was quite set on this, but now I'm considering actually reducing this to 3 x 5.12kWh batteries and using the R18k from the battery to purchase and install a heatpump for hot water instead of just brute forcing the water heating through the geyser.  To me, this makes a lot of sense as I can get a 3.6kW heatpump with installation for that price, and it uses around 860W nominal, or around 1.1kW peak.  That's power I can easily run off the generator or even sacrifice 3kWh on the batteries for, if need be, to get a full geyser boiling hot.  The heatpump also works at night, when there's no solar, and it works even in rain, cold, etc.  I need advice here for this.
16 x 550W panels.  Brand doesn't matter much, this seems to be a common factor in terms of pricing so I'm happy with this. I'm planning two strings, one facing East-North-East and one facing North-North-East, but this is debatable and optional and whatnot.  I can tweak this, but I'm clueless as to how to plan for it.
 
 

Is this the same make and model as you already have?
under LiFePO4 batteries you get 15 cell versions, 48V nominal and 16 cell versions 51.2V nominal, they do not co-exist on the same inverter(s)... you also get NMC type Lithium Ion batteries, usually 13 cell batteries, probably around 48.1V nominal, either way these 3 batteries will not co-exist, so for your setup, you'd need to ensure that whatever you are adding to your existing battery, is the same cell chemistry and number of cells in the battery...
If you have ordered the same make & model battery as you already have, then you can ignore the above paragraph...

Any 5kW (or larger) inverter is likely to be 48V, so your existing battery won't do... also... 5kW Deye and Sunsynk inverters, are not really ideal for the current crop of 500+W solar panels, since they usually do 13+A Isc and the 5kW inverter were originally limited to 11A on the Solar panel side, Deye will either have to redesign the solar DC end to cater for higher current or you may need to look at some other or larger inverter, the 8kW Deye I think can handle higher current on the Solar input end, which would work with the larger solar panels.
If money were not all that important on going solar, my suggestion would be to look at Victron MPPT and Victron inverter with some self assembled LiFePO4 batteries using EVE cells with a JK BMS... Victron pricing has improved, compared to when I first went this route in 2020 and getting EVE cells from some outfit like Apexium can certainly save you a bundle, compared to a prebuilt battery that most likely will come with a poor excuse for a BMS.
Either way, good luck on your setup, may you get to the point where I am, off the grid and keeping the lights on...

You don't say where you are, but you should take some precautions and expect some visits to inspect the meter.

Your useage and thus your purchases are going to be low. This will likely cause a blip on the service provider's system and they will send people out to have a look. They are looking for bridging of the meter. It is nothing personal - don't feel accused. The guy who comes out is just investigating. There is another, legitimate reason why your use is low, so they should not find against you.

From that comes another concern. Here in Johannesburg, in the areas serviced by City Power, if you don't feed your meter for (I'm told by one of their technicians) three months then their systems flag you for disconnection. Check with your service provider and see how long you can leave it. Or just buy a small amount each month.

They now know you have solar installed. I speak again as COJ customer. In theory, for some years now, inverters and batteries do not have to be declared, but any system that generates power  (which would include roof top solar) and has any sort of connection to the grid (even if you don't use that connection) has to be registered with the municipality. This is not an entirely bad thing (in Jhb) as part of the registration process involves them testing various safety features of your system. So I now have a nice letter saying that my system is fully compliant and I have given my insurers a copy. In Johannesburg, at the moment, they are allowing retrospective registration. IE you installed without applying first (which is how it's supposed to happen), but you're talking to them now and they will register the system as long as it passes muster (you also need an engineer to sign off). At some time (unknown to us) they may start enforcing this by-law more vigourously, and under those by-laws they do not have the right to remove your system, but they do have the right to disconnect you from their grid. 

If you are feeding back into the grid, the new meter is probably going to block that. Either by tripping, or by just not allowing any flow from the house to the grid. This is the situation I have, but (again, in Johannesburg) the tariffs are so unattractive that I have no interest in feeding back, and so I have set it not to, which gives my inverter a breather when the battery is charged.

There is always some curve ball in life that upsets the plans. Yesterday there is commotion in the street as the pre paid meter squad is ripping out meters out of the street box.

My neighbor who has the same system as me is one of the victims. The contractor handed him a pre paid meter and said plug this in, it should work.

Issue no 1

Non of his plugs would work to power this thing. The contractor is saying that he needs a direct to Eksdom plug. Like me his system is all on essential there is no split DB.

How do we fix this ?

Issue no 2

I have ordered a 2nd 120 amp battery. Please let me know if this is right.

Switch everything off

Connect red to red

Connect black to black

Connect communication cable

In my manual for the battery it states for ADS, set dip switches

0 off, off, off, off
1 On, off, off, off

Turn on inverter

Turn on batteries

Turn on PV

Turn on AC

Does this sound right to you.?

Thanks in advance.

This is a common issue with pre-paid meters. The interface unit (what you use to enter the tokens for your purchases) communicates with the actual meter via the house wiring. The moment you have anything other else between the interface and the unit the communication breaks down and although the meter itself will still work (whilst you have a credit) the interface unit will have no communications with the meter because of all the circuitry between the two. Remember that in your scenario, everything is connected to the output side of an inverter.

I had a similar problem when I got a new pre-paid meter fitted earlier this year. One solution for me was to just plug the interface into a non-backed up circuit. EG the outbuildings. But that would be a problem for the wife. Everything inside the house is backed up, so I had an electrician fit one  plug that is directly connected to the incoming grid feed. This is clearly labelled as being connected to the grid, not the inverter, and has it's own breaker.

Problem solved. The meter now stays fixed to the wall, next to the inverter, and I don't have to run around in the dark (and sometimes the wet) to load a purchase. A beneficial side effect is that the meter has it's own power/status LED. Now nobody has to decode the row of LEDs on the front panel of my Goodwe, or consult an app on their phone. If that LED is off then the grid is down.

Try and get the batteries up to the same voltage, otherwise you get a big spark and might cause issues, do you have a busbar that you connect them to? Did you mean 120 KWH battery, that is huge?

Pre-paid meters (at least in Zimbabwe) come in two parts; the main part that is connected to the utility directly and power runs through to your house/loads and a second human machine interface (HMI) unit that allows you to enter recharge codes, check balances etc. The HMI is typically plugged into a free socket and communicates via the socket wiring back to the main unit. You do not need the HMI connected at all times but to check balances, enter voushers etc it needs to be connected to the main unit. When an inverter is inverting and supplying power, it may or may not break the connection back to the utility depending on inverter design and/or anti-islanding requirements. I suspect this is why the contractor said you need an Eskom only socket.
Hopefully your installer included a bypass switch for your inverter so that you can remove the inverter from circuit and run solely on Eskom? This would accomplish the requirement of having a Eskom only socket and allow communication between HMI and main unit when it's needed. It is a good back up to allow your system to run while the inverter is being maintained or if there is a failure. You might want to have an Eskom only socket fitted near your utility connection to leave the HMI plugged in for ease of use?
Regarding your new battery:
Double check warranty and wiring regulations regarding fusing and battery connection. Some manufacturers require independent fuses and connections to a bus bar per battery I would typically recommend that the batteries are turned on before the inverter Other steps all seem fine. You should also check the maximum allowable charge current to the battery. This may need to be adjusted.

2 pole WEG 1.1kw
AC Supply: 1ph, 230V, 50Hz 
Rating at 230V 50Hz: 1.1kW 2880rpm.
Power Factor: 0.92
Efficiency: 81%
High starting torque: 194%.
Full Load Current: 6.32A Start Current 20.13A for 0.8s
Locked Rotor Current: 46A for 6s
Full Load Torque: 3.34Nm

So make sure your pump or bearings are not causing the motor to be locked in start up. Do a physical check on motor and pump by turning the impeller by hand it should be nice and smooth.

Below spesifications for a WEG 1.1kw capacitor start/ capacitor run motor.
 Supply: 1ph, 230V, 50Hz 
Rating at 230V 50Hz: 1.1kW 1650rpm.
Power Factor: 0.91
Efficiency: 76%
High starting torque: 200%.
Full Load Current: 6.92A.                  Start Current 20.76A for 0.8s
Locked Rotor Current: 44A for 6s
Full Load Torque: 3.65Nm

You can work on 6x1.1 kW for less than 3 sec. Thus we'll inside the max that the inverter will allow provided no other high power loads on or a fridge starting at the same time. 
It is all a sum of numbers game. 

Do you have grid? 
Test the pool motor on the grid then you will know if the cap is faulty. 
Caps can go for many years. My lawn mover is now going for 34yrs. Even with the vibration. 
 

Thanks @Sc00bs
Appreciate the comments
 

Update:
I bought a Pro 5 data logger and with a little help I have managed to get it all connected for the app Smartess and the web dessmonitor.
So far so good, I can pull much more info than just from the panels on the inverter and battery.

I am no expert but felt sufficient enough to DIY a system. For this I chose the Solarwize 5.5kva inverter, the 120 amp Lithium battery and the 440 W panels.
I installed in Feb 2023 and to date have had a very pleasant learning curve and am more than happy with the results. The inverter is a full hybrid that allows for AC, PV and battery and if I understand correctly it also allows blending other than just a straight bypass.
The battery is not Lifepo, it is NMC and is very robust. Having 120 amps gives me enough to use the SBU setting early mornings when there is not enough PV. As soon as PV is enough the battery recharges quickly and even with a 3kw geyser, I rarely go below 50% DoD. The battery has a panel for monitoring SOC and overall and individual cell charge and the BMS works well for balancing. All the usual over/under V protections are there.
It also has a SOL setting that allows for PV to power everything and will also recharge the battery with anything not used for the load. The panels are 2 strings of 5 into a combiner that gives 240 V and I have limited the amps to 30.
Cost of this system for the three components, inverter , battery and panels was R65 000 and around 20K for the balance of the install, wiring, fuses, breaker boxes for AC/DC, changeover switch and automatic voltage control.
There is a dongle available but I am struggling to get this to work on account of me being BBC (born before computers)
Time will tell but for the cost I am more than happy with the end result and the daily functioning of the system. I am also about 2 thirds less on my Eskom bill than pre system.
Does anyone else have Solarwize products and would like to share.

I agree with @Bobster.  I think using the gennie is likely to be problematic.

There are 4 possible solutions.  All problematic in one way or the other:

1. Mechanically - Modify your generator to have a very large flywheel.  Any load variation will be dampened and the AVR and governor will have enough time to keep the speed and voltage within acceptable norms.

2. Electronically - Replace the genie with a so-called inverter generator.  Simplistically you can see that as a conventional generator with an AC/AC inverter.  These generators are expensive.

3. Electronically - get yourself a 230VAC battery charger that is rated for 2KW or thereabouts.  For example, there is a 48V 100A EG4 "Chargeverter".  These are also very expensive and will cost as much as a smaller inverter.

4. Electrically - If you don't have solar panels you could possibly use the MPPT input.  I am not familiar with the specifications of the Luxpower so you would first need to check the maximum MPPT input voltage.  In theory, you could rectify the genie AC to DC and then fit an electrolytic smoothing capacitor to create a 320VDC voltage.  However, MPPTs seem to be very temperamental regarding their input as well.  SunSynk apparently recommends connecting a 1 or 2KW "resistor" in series to simulate a power source that looks more like the output of solar panels.   Also, 320VDC is more dangerous than 230VAC and one would need to look carefully at the various parameters of source impedance, power, voltage, input current, etc.  It would also be hugely wasteful in power.  That 1 KW resistor would act like a heater.  This might be the cheapest solution, but I would not recommend it.

Generally a generator cannot be modified sine due to the rotation through a magnetic field. 
Modified sine are electronically created with components in inverters as pure sine is a lot more expensive. 

I don't think it's case of dirty V pure, but certainly inverters tend to be picky about their input.

My inverter, for example, disconnects if voltage gets too high or too low, or if frequency drifts away from 50Hz. IOW it wants input that is within certain parameters.

If anything drifts outside of those parameters, the inverter stops accepting the input, but keeps on it monitoring it. If things improve and stay improved then the inverter will reconnect.

I think this is the general area that is likely to be problematic. The load on the generator will not be constant, so it's output will be varying, and if the voltage drops (or rises) by too much, or if the frequency varies only a little from 50Hz, then the inverter decides to disconnect.  So unless you can get a fairly stable output from the generator (which will react to the load), it is likely that the inverter is going to connecting and disconnecting a lot. .

And settings on the inverter may need setting. My inverter running in it's default mode will draw from the batteries rather than charge if "grid" is present and PV can't meet the load, and it will do this until SOC goes below 40%. At that point it starts drawing from the grid, but will only draw enough to service the backed up loads, it still doesn't charge the battery. I can make it charge the battery, but it requires intervention by me, it won't sommer just happen. Also it will likely draw at least 2kW for the battery, over and above the other loads, so the generator has to be able to handle the combined load.

And now I can see a scenario where the inverter starts charging, load on the gennie goes up, so the gennie's output drifts and the inverter disconnects. At which point the load on the gennie decreases until the inverter reconnects and starts charging again. At which point the load on the gennie goes up. And so we continue the unhappy dance.

OK... Eskom are running generators, but big-ass generators that can handle a large load and (mostly) stay within the bounds of what my inverter deems to be an acceptable signal. So maybe if your generator is big enough... Since a 5kW inverter can back up 5kW, and can also recharge at 5kW, a 3.2kW gennie seems likely to be too small, unless you are willing to turn everything in the house off and just recharge the battery.

Even assuming a big enough gennie, we also have the current load shedding schedules with multiple slots per day, and the timing of the slots varying almost every day. So my manual interventions have to be planned, and I need to be able to do that at the correct times on any given day. So that will not be good for my blood pressure.

Or do I have it all wrong?

not with a buck converter type MPPT charge controller, it'll take the 70-odd Volt by 3.8Amp around 266W and bring that down to, let's assume around 14V and thus 266W/14V=18A or so, the conversion ain't 100%, so you need not parallel up the panels, since the charge side specifies
the 18A is based on great sunshine and the panels facing the sun directly...
however, if you want to parallel up the panels, I don't think there's a problem with this, just a whole lot more copper from the panels to the MPPT to cater for the higher current...

The best person to confirm what is inside the compressor housing would be Johan in Pretoria as he has been repairing these units for very long and at any time he has a garage full of fridges submitted for repairs. 
It does not sound practical to use 220C AC to step down to 12V and rectify to DC just to convert back to 3ph AC inside the compressor housing. 

My Waeco CF80 fridge/freezer works from 230v ac or 12V dc or 24V dc. The 230v ac gets converted to 12v dc which runs the 12v dc Danfoss compressor. The original power supply stopped working on 230v Ac and cost a arm and a leg to replace. I bought and wired a cheap 230v to 12v dc 20A powersupply,  from the china mall, in its place and it has been working wonderfull sofar. 

Perhaps one should look at what the OP mentioned. His fridge as with most camping fridges Do work with a compressor. Your example of 40 years ago is not commonly used on fridges and for sure not on camping fridges. These days the 220V is going through a step down power supply that provides the 12V from AC and the 12V battery input powers the compressor directly. 
For sure no fancy inverter system to start the 12V DC compressor. 

when you measured the voltage of the panel strings was that disconnected from the inverter? if so,  they were not producing power, or at least the potential power was not being used/consumed and they should have been in Voc state, Voltage Open Circuit, if this was the case, you should have seen 49.57V x 5 panels being 250-odd Volt, but even under load/producing power their Voltage should be 41-odd Volt per panel and thus be sitting at more than 180V per string...
 

Hi, not sure what you mean by not producing power.
If for example I run my home office, which is around 400 W and then put on my 1.1Kw pool pump, I can see generation of around 1.5Kw coming from the panels. I can see this when load shedding is in effect. The inverter, if I am reading it right shows nothing being drawn from the battery.
The most V I have seen is around 220V, the most amps I have seen is around 12 A.
I have the system on solar priority, then utility, then battery. My battery is almost always full.
Thanks for all the replies, it goes a long way to understanding the system.
If we don't speak again today, have a great weekend.
PS: regardless of whether I have a perfect system or not. It beats the hell out of 8 hours or more a day load shedding.