14 minutes ago, SilverNodashi said:

Are you converting? Nice touch

Nope ... but if someone does not want Victron, BEFORE they go Voltronic, go GoodWe or ABB. 😋

On 2019/04/05 at 8:45 AM, PlanB said:

Hi Forumites... I'm starting out on this journey and already have sooo many questions.. I've been lurking in the shadows, reading many posts and I want to know the following.

I'm on a smallholding outside Centurion.

 

I will try and answer as much as I can, and others have given some responses already

On 2019/04/05 at 8:45 AM, PlanB said:

I've been looking at the InfiniSolar Plus 3K  or maybe the Goodwe GW5048 Em 5KW or Infini Solar 5kW Dual MPPT Hybrid Inverter

1. Why would one want to have an inverter that can be connected in Parallel?  Would it not be better to have one 10Kw hybrid than 2x 5Kw

Simple. You might start out with a 5Kw today but decide to upgrade in future. Everyone doesn't want 10Kw so 5Kw is sufficient. Or you might want a 5KW on each phase of a 3phase setup. With a 3phase 10Kw you essentially have 3.3Kw per phase.

The Goodwe's can't stack.

On 2019/04/05 at 8:45 AM, PlanB said:

2. Almost in the same area; Why does some Hybrid Inverters have Dual MPPT?

 

This is quite handy if your roof isn't north facing and you need to install an East and West facing PV array. And also handy if there's bound to be some shade at some stage during the day - then only one string gets affected.

On 2019/04/05 at 8:45 AM, PlanB said:

3. There seems to be a few Voltage variables that Solar panels have; Voc(open Circuit) and then Operating Voltage (12/18/48)  Which one is most important when pairing a PV to the Inverter ?
 

As the name, Open Circuit, implies, this is the voltage that could potensially be reached when there's no load. Others have explained this in details as well. Both are important when calculating a system size.

On 2019/04/05 at 8:45 AM, PlanB said:

4. Some PV max voltage can harm the Inverter if it is more than the inverter can handle. How does this work (in which circumstances can this max voltage be "activated"?

In simple terms, on a clear sky, cool / cold morning, the system voltages can reach higher levels than what the MPPT can handle. This could happen at 7am when it's -2 degrees outside.

On 2019/04/05 at 8:45 AM, PlanB said:

5. It seems that very cold conditions also have an impact on the voltage , why is this ? ... Maybe in general if someone can just summarise the voltages, as my head is spinning from trying to make head and tails reading Wikipedia and other websites that explains PV panel voltages

 

As above.

On 2019/04/05 at 8:45 AM, PlanB said:

6. The InfiniSolar Inverters are sometimes branded as Mercer and sometimes Voltronic and sometimes ?? this seems confusing.. is there a Branding one should avoid (e.g. InifiniSolar 3K PLUS Single Phase Hybrid Single MPPT Inverter Charger bi directional with grid 48V DC(SOL-I-IS-3M)  .../// Mecer Infinisolar 3KVA . Plus Hybrid Inverter Single Phase)

 

Voltronics is the manufacture. Though MPPSolar also claim to be the manufacturere. Mustek, one of the big IT importers, re-brand most of their equipment and sell them under the Mecer (or Mustek) brand. Pinnacle rebrand their equipment under the Proline brand,hence having proline inverters in the market as well. It's still an Axpert or Infinisolar though. And I think Rectron sells it as RCT, which was the original brand of the first UPS' that Voltronics made, and can still be brought as RCT.

On 2019/04/05 at 8:45 AM, PlanB said:

7. From some posts it seems that Mono PV is better than Poly , but then someone mention something about operating temperatures ,, which is best for South Africa?

Polycrystalline tend to work better in the warmer areas of the country. Thin Film work even better with lower light so they produce a bit more power, earlier in the mornings and later in the afternoons / early evenings.

On 2019/04/05 at 8:45 AM, PlanB said:

8. I get my mains power directly from Eskom , I have 3phase power. In the main Box I have 3 meters, One is a grey box with a blinking light, the other 2 are the old type with the spinning wheel. I'm hoping that I can put all the loads that will be paired with my solar setup on one phase and install a hybrid Inverter and hope to push back power into the grid, making the wheel spin in reverse  during the day and forward during the night when I use Eskom power... As I'm not on Jhburg Power or Tshwane Power, will I have to register and apply for this from Eskom or do I just sneak this in and hope they never notice?

There are many more questions, but for the moment these are the few I find most pressing.

Hope the Forum will shed some light (solar) on these 🙂

Putting all your essential loads onto, say, the red phase and the non essentials split equally between yellow and blue is not that difficult. Just make sure the neutrals are split properly, and as far as possible that the loads are still balanced between the 3 phases.

I have not dealt with Eskom directly yet, so not sure what is involved.

On 2019/04/05 at 8:45 AM, PlanB said:

There are many more questions, but for the moment these are the few I find most pressing

Feel free to ask Perhaps open a new topic per question, as different people monitor different topics and will respond accordingly.

 

 

10 minutes ago, The Terrible Triplett said:

Nope ... but if someone does not want Victron, BEFORE they go Voltronic, go GoodWe or ABB. 😋

If it comes to Infinisolar, I would think again. ABB is in a bit of a different league though. In many cases Infinisolar has advantages over Goodwe. For one, the backup power is not limited to 2.3Kw or 4.6Kw, but limited to how much PV / battery power is available. And it can run off Lead Acid batteries, which Goodwe prefer not to.

2 minutes ago, SilverNodashi said:

... limited to how much PV / battery power is available.

Wonder if that will solve the max 3.5kw that the regulations stipulate ... 

On 2019/04/10 at 9:28 PM, The Terrible Triplett said:

Wonder if that will solve the max 3.5kw that the regulations stipulate ... 

I doubt it since the unit is rated at 4kw on the PV side. So then you need an 80A breaker

On 2019/04/06 at 2:03 AM, Coulomb said:

Mainly for expansion; you buy the 5 kW model now, and buy another 5 kW later when you can afford it.

But there is also the idle power drain; you can switch off one inverter at night (possibly automatically), and save the idle power load, if you don't need it. Our patched firmware (for Axpert off-grid models, not the hybrids you are considering) even has a facility called Dynamic Load Control, which allows you to turn on and off some of your paralleled inverters with a command over the RS232 port.

Hi Coulomb,

What would happen with the Goodwe 5kw inverter if your load was bigger than 5kw, would it trip or would it switch over to grid feed until the load was back within the inverter parameters? Not talking about it handling spikes, but a heavier load for 30 mins for example? 

1 hour ago, Kilowatt said:

What would happen with the Goodwe 5kw inverter if your load was bigger than 5kw, would it trip or would it switch over to grid feed until the load was back within the inverter parameters? Not talking about it handling spikes, but a heavier load for 30 mins for example? 

If the bigger than 5 kW load was on the "essential loads" output, it would have to trip. But presumably you'd organise your loads so that it was extremely unlikely that this would happen.

So let's consider that the >5 kW load happens on the grid side. Now the Goodwe doesn't care, as long as the grid can handle the load (and 5 kW is almost trifling for the grid, so let's say yes it can). But if the Goodwe has say 3 kW of solar power available, it can use that to partly supply the load, so the >5 kW load becomes >2 kW from the grid.

This is where hybrid inverters shine: any time that the total load exceeds that of the inverter's rate power. Even an Axpert King can't do much with that, other than hand the while >5 kW load over to the grid, and charge the battery if it's not already full.

But if you keep several large loads (e.g. geyser, oven/stove, large air conditioner) on the grid, then a 5 kVA inverter can likely handle most loads most of the time. In that case, the advantage of the hybrid starts to fade, and it has no advantage over the Axpert King (ignoring those few times when the combined load exceeds that of the inverter). Even ordinary Axperts do OK in this scenario, though it helps if your family is "load sensitive".

Thanks so much for that explanation. 

So with loading the on grid loads and only keeping lights and plugs on the off grid essential loads it should be easily achievable to use a smaller inverter like a multiplus II 48/3000 to run a medium size house without having to be too load sensitive? This might be a better way to start off my solar journey than by shocking our selves into a load sensitive lifestyle. Obviously ROI will just be longer?