Another issue is the speed at which it can reconnect the grid when overloaded. Will sometimes trip in overload before it can reconnect.
If you go that route, you’ll have to teach the fam things like “If you want to use the kettle and the microwave at the same time, turn on the kettle first” so that the inverter switches to grid with the kettle load only instead of trying to do it with the microwave already running, and then adding to kettle.
Boom. (Well… click.)
How sure are you about that? That ”at the same time" seems pretty significant and deliberate to me.
There you have it – weasel-words which are impossible to objectively quantify until you buy the thing.
You don’t have these issues with more reputable brands. We know from experience that Axpert & Voltronic inverters cannot blend, so for them “at the same time” means the system will automatically select without user intervention, but won’t blend.
The Growatt is (was?) a rebranded Axpert, so logic follows that it will have the same limitation, but it may not. Because the cheaper manufacturers tend to use weasel-words like this in marketing and manuals, it’s impossible to know until you have the thing, even if it ends up being what you want.
If you’re willing to risk it, please report back, that’s how we learn.
Speedster, get an inverter with an NRS certification.
Ok. Time that i comment. Stay away from Growatt. If you want to pay school fees, then you can play there, if you don’t want then go Sunsynk.
There is loads and loads and loads and loads of more complaints on the other forum and fb. It’s a undercover voltronics unit. It’s a hit and mis with the growatt brand. I know someone that installed one and i told him his going to have a s^#*@ load of problems, but the installer is the pro and i know nothing, and this with revov batterye, the guy next to him did the same install setup. 4 weeks later he came nocking on my door to help him. His using more grid then ever and nothing is working correct. The guy next to him already removed and moved over to sunsynk.
I have no personal experience of this so going via google-Fu…
The 5000 SE 5000 ES can technically use grid and solar at the same time BUT it is dependent on the battery being actively charged. If the battery is fully charged the solar gets shutdown - so you to have to manually every night make sure to set the system to discharge the battery, so that in the morning the battery will require a recharge where you once again have to make a setting change to the system (reference - about the 6th post the member posted details to be able to view system details → when you go back to first week of September 2021 you can see the difference the settings made to solar production).
Also, when connected to lithium bms systems the system might do things you did not expect (and options like limiting charging current is out of your control).
A definite drawback of the growatt system is that whatever you want to power through the help of solar must be connected to the output - which if you include geysers and ovens can make for some interesting overload scenarios.
If the cheaper growatts don’t blend, then your perceived savings ( which doesn’t seem that much in the bigger scale of things) are going to be eaten up over time with the additional draw from grid.
It’s also not nrs certified so when the politicians get their act together eventually, you are going to be forced to remove it. If you cannot get a coc for it, means your insurance becomes a risk should something happen.
I think most of the comments on this thread have suggested to get the sunsynk.
If you are still willing to get the growatt, then it’s best to speak to someone who has one and look at the cost savings vs disadvantages but bear in mind, most people that have it are not going to say it was a bad purchase. That’s unfortunately human nature.
Agreed. If you want to get an off-grid inverter, you do just that. Go off-grid. Flip the main breaker and run your whole house. Otherwise that few thousand you are saving will be penny wise and pound foolish.
That said, there are Growatts that seem to be copies of the Goodwe, but they also look like the Goodwe, so it is easy to spot.
Indeed. And I’ve even seen rebranded versions of the Axpert King, which I am also told can “blend” power (but it has other limitations, a maximum power limitation for example since everything passes through the HVDC bus).
Let me just say, lest it seems like I am supporting a unit from a competitor: There is a reason the Blue Inverter is so popular. It is well supported, it’s good quality, it has an excellent warranty, a good track record. If it was me, I’d install a PV-inverter now (since that is your primary concern) and add backup later. But of course I am biased… 
I contacted the Growatt technical support engineer for South Arica and herewith his initial response to my email. Doesn’t exactly fill one with great confidence as to the support going forward.
Good morning
I have received conflicting reports so thought I’d find out directly from the source - is the SPF 5000 ES NRC approved?
Kind regards,
Hi Speedster
I am not sure if i understand you.
The rest of the conversation wasn’t exactly inspiring either.
Well, at least he was able to help you with your decision…
Is the earth neutral bond on the Sunsynk only necessary if there are loads before the inverter, or is it a standard requirement?
Its a standard requirement. You need to bond the earth and neutral in the event of a power failure to ensure that the output earth leakage still operates correctly.
You can use a normal 25A or 40A contactor with a 240volt AC coil
You are the second person to mention something like this in the last week. I don’t know where this info is coming from.
The neutral earth bond is actually required when the inverter is in islanding mode. In this case, the loads before the inverter are anyway isolated so it doesn’t matter.
What does matter is the loads after the inverter. Depending on the type of electrical installation, you either have a earth spike in your property or it comes from the council.
In the case of my house, the earth is coming from the council and is bonded to the neutral at the main distribution box somewhere on the street. That’s the reference for earth and the neutral will be close to zero volts because of the bond. So when the grid fails, the inverter is in islanding mode, meaning that the inverter output neutral and live is disconnected from the grid live and neutral which also means that the inverter neutral is not at the earth reference of almost zero volts and the live also has no reference.
When I did my install, I had 230v between live and neutral, and around 120v between earth and neutral and 120v between earth and live. So the earth neutral bond is used to bring the inverter output neutral back to earth and create a reference.
There’s some installers and some electricians that will tell you that it’s not needed. Most, don’t know why it’s needed or how to properly test. I’m pretty sure that it’s a requirement from SANS perspective and it’s relatively cheap in comparison to a inverter install. Some will also tell you that the sunsynk has it built-in which isn’t true.
Please don’t waste your hard earned cash on the box that the other forum sells for around R2500 -R3000. All you need is a contactor or relay with a 220v coil. I’ve used a 40A relay from communica that is around R350 (when I purchased 2 months ago).
Remember, you can only bond the output of the inverter and only when disconnected from grid. The sunsynk inverter controls the coil and you connect the load side neutral and earth to the 2 terminals of the normally open relay / contactor.
I just want to add, since these are kinda related…
Do not disconnect the grid earth under any circumstances. You should bond your post-inverter (load side) neutral to earth if and only if you’re islanding, i.e. disconnected from the grid as @Vassen said.
I’ve seen people take this to mean that you’re creating a new earth, which is not the case, you’re shifting the bonding point from the somewhere upstream to a local point, but there is still only one, and it is still the same earth.
(In some circumstances you may add extra earth rods or mesh grids or so-on, but I’ve never seen someone create an entirely separate earth and live to post about it.)
If it is connected to the house, it needs to be TN bonded.
It is also required for reliable RCD operation. On this topic I need to elaborate a bit. An RCD (or earth leakage) will work even if there isn’t a TN bond. The RCD’s job is to disconnect the supply if it sees 30mA or more difference between the two supply lines.
In an unbonded system with a single earth fault (you, with your bare feet, touching a live wire), the impedance might be too high to pass 30mA, and so the RCD will not trip. But… you likely won’t get killed either, since the current is too low.
Now say your cousin, touching the neutral wire, is also standing barefoot in the slightly damp soil. Now you have TWO earth faults, and now the odds are that both of you is going to feel a bit of a tickle. If that tickle is above 30mA, the RCD will do its job and protect both of you from dying.
BUT… it takes TWO earth faults before the RCD can do its job, and that is not on. And that is WHY we bond T and N. It is so that a single earth fault of 30mA will disconnect the supply.
And this is why I cannot understand how people can spend 50k+, sometimes 150k+ and skip something that is <R500 ignoring the legalities of not installing it.
Each to their own though.
I’ve given up trying to convince people who have their minds made up.
Well put…
Actually, in that case the two faults will largely cancel each other out. Your cousin needs to be touching neutral at some point before the RCD for it to work…