1 hour ago, plonkster said:

Yup. In my experience the term "hybrid" got hijacked at some point.

Hybrid normally means a thing made by combining two or more other things. In this context, it means an inverter that combines the grid-tie ability of a PV-inverter (this is the name Victron uses to avoid confusion) with the backup capabilities of a battery inverter.

Then a few months later I saw someone advertise an Axpert as a Hybrid. Upon investigation, I found the reason for that is that it combines a solar charger and an inverter into one unit.

Roll on many years later and many people insist that the Victron inverters are not hybrids (they are) but that the Axpert is!

Talk about an inversion of meaning!

🙂

Edit: Just to add, the Infinisolar is indeed a hybrid. It ties with the grid like a PV-inverter, but it also has battery backup.

No you do not need another inverter to make use of the battery power with the infinisolar  plus 5k unit for power failures. It is grid tied unit with solar and battery backup with a 5Kw output. That diagram shown to me is confusing. Why would you not use the infinisolar for load.

Edited January 20, 20206 yr by Peter Topp

17 minutes ago, Pietpower said:

So it does not switch off when the grid goes down?

Perhaps saying "switch off" is not correct. The important thing is that a grid-tied inverter (be it PV or hybrid) must DISCONNECT from the grid when it goes down. Traditional PV-inverters do switch off as well, though some models may remain on and power themselves via PV.

The important part is the disconnection, not the switching off.

Hybrid inverters will have two AC connections, one is an input from the grid, and the other is an output for loads.

While the grid is up, it can feed power to the grid via the input connection AND power to the load via the output.

When the grid is down, it disconnects the input, and only the stuff on the output is powered.

The Infini, goodwe and Victron inverters all do this.

21 minutes ago, Pietpower said:

- It connects on the grid side so you don't have to split the DB

You probably still have to split the DB if you only want selected loads to have backup. You would put those loads on the output connection of the inverter.

22 minutes ago, Pietpower said:

- If your load is more than 5kW the balance will be from eskom

Yes.

22 minutes ago, Pietpower said:

- During power failure you are limited to 5kW thus need to manage heavy loads

Correct, hence the splitting of said DB.

 

49 minutes ago, Peter Topp said:

No you do not need another inverter to make use of the battery power with the infinisolar  plus 5k unit for power failures. It is grid tied unit with solar and battery backup with a 5Kw output. That diagram shown to me is confusing. Why would you not use the infinisolar for load.

Yup, I know, sorry if it didn't look like it 🙂

 

5 hours ago, Pietpower said:

Found this image on the forum

As per @Peter Topp, that diagram is crazy. Just ignore it.

28 minutes ago, Coulomb said:

that diagram is crazy.

I think I remember where it comes from. Some infinis (all?) can run without batteries. Then they work like a traditional PV-inverter and you have no backup. Someone was considering using the Infini sans battery in this manner, and then using an Axpert as the backup part. Why? No friggin idea... you could just use the Infini for backup. Maybe there was a reason, who knows...

8 hours ago, Pietpower said:

Does it need a secondary backup / off grid inverter to make use of power failures to draw from batteries?

No, The infini does it itself. So no need to have the Axpert in the system... [O wait, saw this was answered]

However, I really want to hit this home:

The Axpert is not a Hybrid at all, people advertising it as such is a bit ignorant of the internationally accepted nomenclature.

Even the makers of Axpert (Voltronic) does not call it a Hybrid, but an Off-Grid inverter. Massive difference. 

Hybrid can use both Grid AND Solar at the same time, Axpert can only use Grid OR Solar at a time. Yes, it switches between the two, so you either have Eskom power or you have Solar/Battery power. But not both at the same time

Infini is also made by Voltronic if anyone wondered...

 

1 hour ago, Pietpower said:

the Infinisolar is a similar hybrid to the Goodwe etc

I've never seen one in the Flesh, but since it has NRS097 compliance (2010), it must contain a redundant disconnecting relay set and therefore I must assume that it must be similar to the Goodwe, with a separate input and output.

1 hour ago, Pietpower said:

I think you just have one electrical cable from the inverter to the DB board?

Indeed, with a non-hybrid grid-tie there is just the one cable.

1 hour ago, Pietpower said:

Or can it still only do 5kW?

I don't know about the Infini, but I am pretty sure it will be similar to the Goodwe, Victron, etc. It has a single inverter component capable of 5kW. This is synchronised with- and tied directly to the grid (so grid, inverter and output are all tied together) and it can feed a total of 5kW into this combined connection. If you have 2kW on the output, then it can only feed 3kW into the grid. If you have more loads than that, the rest comes from the grid. If the grid fails, the total is still just 5kW.

Inverters may have different limits depending on whether the grid is there or not. I seem to recall the Goodwe's backup capability is lower than its grid-tied capability (someone correct me please?). The Victron is the other way round, it limits itself to 80% while grid-tied. But the basics remain the same: One inverter component is shared between grid and output.

15 hours ago, plonkster said:

Someone was considering using the Infini sans battery in this manner, and then using an Axpert as the backup part.

But the crazy diagram shows the battery connected to both inverters.

10 hours ago, DaveSA said:

Not quite so... the Axpert King does act as a Hybrid and even more ! 

Indeed, it seems that all the Axpert "off-grid" models that take up to 450+ V PV input have modes where they grid tie. They're a bit quiet about that, possibly because this is against regulations nearly everywhere (unless these Axperts have the appropriate certification, and that would send the price up too much).

9 hours ago, Pietpower said:

They told me the Goodwe have both the same. 4.6kVA each if I remember correctly. This a total of 9.2kVA 

If I recall the block diagram of that inverter... then no, still just 4.6. But I could be wrong, I don't know that unit very well.

39 minutes ago, plonkster said:

If I recall the block diagram of that inverter... then no, still just 4.6

correct.

14 hours ago, plonkster said:

I seem to recall the Goodwe's backup capability is lower than its grid-tied capability (someone correct me please?

Depends on the model, ES vs EM models. EM has full capability if I recall.

14 hours ago, plonkster said:

The Victron is the other way round, it limits itself to 80% while grid-tied

I was not aware that it reacts differently to when the grid is down? So it is not 80% regardless?

36 minutes ago, PaBz0r said:

EM has full capability if I recall

it is the other way around. The EM series has a lower maximum (50%) "back up" and battery charge output compared to the ES series.

1 hour ago, PaBz0r said:

I was not aware that it reacts differently to when the grid is down? So it is not 80% regardless?

Yes and no. It's rated to run at 80% power continuously, assuming ambient is not crazy. When you go over 80%, it starts to run hot and if you do this for too long (usually around the hour mark) it will overheat and shut down. But because in an off-grid application an inverter is sized for the peak power, and you generally run at the peak for only short periods, you're given that extra 20% without some electronic nanny stepping in and shutting things down.

But when running grid tied, it is permanently limited to 80% of the total capacity to keep it cool.

So yes, when running off-grid it can do 100%. But also no... it cannot do it continuously, so you could argue that it is always best to stick to 80%.

My 3kVA has done 3.2kW loads during load shedding for example. Really short periods though, boiling a kettle short.

16 minutes ago, plonkster said:

My 3kVA has done 3.2kW loads during load shedding for example. Really short periods though, boiling a kettle short.

I have seen the 5kVA run more than 4.3kW when the grid is up, so it makes sense that the ambient allows it to do so , so doesn't seem to be a hard hard stop

On 2020/01/16 at 7:39 PM, Rclegg said:

Great video, thanks for sharing it. It does help!

That's a deal breaker then. Did not know that!

So a hybrid system, is what I need then. I am going to go with a 5kVA until as well. As I am sure our usage will go up once the wife and I have kids etc. 

I was considering getting the PylonTech batteries. A 2.5kVa (I think) - I hear they will give me a longer lifetime (like 10 yrs - 6000 cycles?) - and as you say, can start off with one and add later?

Thank you very much for this @Rautenk - very informative. I've started logging usage and this weekend will test peak load in a load shedding scenario. 

Thanks @Marlonw - the Goodwe 4.6kw looks really good. However out of mu budget right now. Will something like the RCT 5000 or the Mecer ones work? And then perhaps I can upgrade it at a later stage?
also Where does one shop for panels? 
 

Hi @LPG I'm in Randburg, Johannesburg. 
Thanks for the info - I'll add your points to my list as well for this weekend to see what is needed and used etc. 

Seems its a hybrid system I want not a grid-tied setup. I will do more research into it. 

 

Thanks to everyone who has replied and given feedback / advise. I appreciate it hugely. 
I will update the thread next week once I have worked out the devices I need on and the max peak load we need to sustain during load shedding.

@RcleggI agree with most of the responses. To go Off grid/grid tied/hybrid is an expensive exercise, however, by starting with a reasonably sized inverter (5kw) is a good option for an average household household. Then expand from their onwards. (R23k)

Solar modules are relatively much cheaper nowadays and could be added as could be afforded.

please look at the attached datasheet, this could give you some insight of what is possible.

You would need to notify your Munic or Eskom and register your project. most have by-laws in place for embedded generation.

I would further advise to make use of qualified licensed electricians and someone with a PV Solar track record.

Good luck

 

Datasheet-MultiPlus-II-inverter-charger-EN.pdf

Look here for LIpo4 batteries, about 1/2 the cost per Kw of Pylontech batteries;

www.LithiumbatteriesSA.co.za

He can build them to your requirements as well. Apparently as long as your battery charger can specify charging voltage and current it will work.

 

 

30 minutes ago, FixAMess said:

Look here for LIpo4 batteries, about 1/2 the cost per Kw of Pylontech batteries;

www.LithiumbatteriesSA.co.za

He can build them to your requirements as well. Apparently as long as your battery charger can specify charging voltage and current it will work.

Excellent, thanks for this.

1 hour ago, DaveSA said:

The advert says 6000 cycles 90%  DoD, but their own spec sheet shows 2000 cycles. I have also found this same 2000 cycles quoted on many of the Chinese sites that supply similar to the Narada  and Meritsun, etc  48V LiFePO4 batteries - so not quite up to the Pylon standard rating (tho' we have yet to see this).

Hi @DaveSA,

Please note that this 6000 cycles claims is just a bunch of marketing bs.

The cells i sell are originally rated 2000 cycles at 100% dod and their remaining capacity will be 80%

Now for the latter, 6000 cycle at 90% dod and you will have 50% capacity remaining.

These are basically the exact same claim.

Hope this sheds some light on the cycle claims.

1 hour ago, DaveSA said:

I would be very happy with that

 

This is exactly my point... it's the same thing... my cells do the same... the bigger number just sounds better....

12 hours ago, Bain Viljoen said:

This is exactly my point... it's the same thing... my cells do the same... the bigger number just sounds better....

Hi @Bain Viljoen you are on the forum as well! 

 

You should have told me you are now shipping to Cape Town! Last time I asked shipping was for own cost... made me not consider your product this time around. 

I wanted also to point out that the DoD for testing to 2000cycles is 100%, so makes a difference if doing 80% DoD. 

Anyway, a few questions on that:

1. Does your BMS allow you to connect old and new batteries in parallel without affecting the new ones.

2. Are you planning on integrating a "smart" BMS and Control system that can do communications (CAM-bus i think is the standard) to any of the main inverter suppliers (or that ICC used with the Axperts).

 

At this stage, I believe the units are sold as "dumb" batteries, fully controlled by the Inverter voltage setting and then heat protected by the internal BMS. 

 

ps. I would still recommend that someone use your batteries due to the price! 

Hi @Rautenk

My BMS would allow this, i am uncertain as how much current will be drawn from the old battery vs the new one.

I would suspect that if you use a 60ah(Old) and a 120ah battery together that the 120ah would be pulling 2/3 of the load and the 60ah 1/3 of the load.

All that my bms will do i stop you from doing overcurrent, under and over voltage.

It does not know that there is another battery connected, it only knows what you are trying to put into it or take out of it.

If attempting to do this you must charge both batteries to a near exact same voltage or you will be having a bad time with the BMS's.

My current batteries do not have heat protection built in. 

I am considering getting a smart BMS but i don't want users to be able to alter the batteries settings. this is my worries...

And honestly i don't have enough capital for so much R&D. I am still in infant stages.

On 2020/01/21 at 7:14 AM, plonkster said:

If I recall the block diagram of that inverter... then no, still just 4.6. But I could be wrong, I don't know that unit very well.

I am running a Goodwe GW5048D-ES with 5.6kWp PV panels and 16.6kWh Pylon battery bank.

In the spec sheet for the inverter it documents that;
the unit can supply 4.6KVA backup power (6.9KVA for 10s)
with grid connected the unit can supply 5.1KVA 

In practise though, with the grid connected and the inverter running at 53Deg C I have seen the unit happily supplying 5.4KVA for over 30min without drawing on the grid.

On 2020/01/20 at 7:04 PM, DaveSA said:

Not quite so... the Axpert King does act as a Hybrid and even more !  It's like a  Grid Tie and UPS combo, and it's been available for about a year already. So all the available solar is utilized and the shortfall comes from the Grid. Have installed many and they are all running perfectly without any issues whatsoever.

 Can anybody else confirm this? 

I can works well

5 hours ago, DaveSA said:

Download the Manual 

Very helpful 🙄

It seems it can blend grid and solar, but it's not true 'grid tied'... it doesn't blend AC but DC. It converts the grid to DC and then inverts to power your load. So you can't have loads higher than the inverter's max (5KVA) connected to solar power. Still useful! Although the efficiency will drop a bit.

Does anyone know if this setup requires registration/sign-off from authorities in some areas?