Axpert inverters any good?

Tim_vb

Tim_vb

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Tim_vb said:
Hi All, Are the Axpert inverters any good? It seems they are a Chinese rebrand by Rectron so it hard to find any reviews of them. I like how they integrate grid tie solar as well as battery backup options.
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You must not have been looking very hard.
https://powerforum.co.za/forum/9-inverters/
http://forums.aeva.asn.au/viewtopic.php?t=4332

Literally thousands of these things have been bought by people all over.
General consensus is they are reliable.

The thing to watch out for is the MPPT, all failures I've seen are as a result of the MPPT going bad.
Not that there are many failures but when it happens it is usually the MPPT.

Tim_vb said:
I like how they integrate grid tie solar as well as battery backup options.
Click to expand...
It is not grid tied. Gried tied means the device back feeds into the grid. Axpert inverters do not do that.

Tim_vb said:
My concern is that they will burn out in 4-5 years and it would have make more sense buying a more expensive model.
Click to expand...
You will be hard pressed to find an inverter that guarantees operation after 5 years. Even among expensive inverters.
Some people have been running Axperts for 5 years now.
But certainly there is no guarantee.

If you spend twice as much that means you could have bought two Axperts.
And new products are coming out all the time.

I wouldn't waste money on a device because they "promise" better reliability.
It either needs a 5 year warranty or it is as good as the Axpert.

More importantly, in 2-3 years there will be more efficient and feature rich products available so what justifies the price now?
 
Grid Tied means you don't have batteries, you rely on Eskom for your device to work.
If there is load shedding your system shuts down.
 
Chuckmyster said:
Grid Tied means you don't have batteries, you rely on Eskom for your device to work.
If there is load shedding your system shuts down.
Click to expand...

Would the Axpert be able to automatically switch from solar to grid if there is insuficient supply from solar panels?

I see Infini and Goodwe do support both grid tie and solar-battery backup programs, switching between these as utility power is available - at a significantly higher cost though
 
All Grid Tied Inverters will switch to Eskom when the demand is there.
ie, your 4kw Grid Tied Inverter is chugging away nice and merry during a beautiful day with your air-con running (2000w) and your swimming pool pump (1300w) is running all day and here comes the In Laws and switches on the kettle (2200w) for a cuppa tea.
You are producing 4000w from the sun.
Less the aircon and pump 3300w.

You have 700w to spare but the kettle (2200w) got switched on.

Your inverter digs into Eskom for the outstanding 1500w to boil for that cuppa tea. Once kettle has boiled your system goes back to solar only.

That is a very very basic briefing on grid tied.
 
Chuckmyster said:
Your inverter digs into Eskom for the outstanding 1500w to boil for that cuppa tea. Once kettle has boiled your system goes back to solar only.

That is a very very basic briefing on grid tied.
Click to expand...

So not to be an ahole but your description is off.
Grid-tied doesn't act as a gating mechanism as you imply.

A grid-tied inverter is in parallel to Eskom. Meaning if your inverter is supplying 2kW then it is adding 2kW to the grid.

If your demand is 3kW, that power isn't running through the inverter.
That is not true as you state it.
The inverter simply adds 2kW in parallel and the other 1kW will be sourced from Eskom.

The inverter adds more power to the power lines, at no point is all the power running through the inverter at a single point.

That is also why grid-tied cannot work if utility power is not available (IE> Eskom).
It isn't a source, it is a supplemental supply.

Axpert inverters on the other hand are UPS with a MPPT controller integrated allow some of the UPS power to come from Solar.
So it acts as a power source.

Completely different design
 
Gnome said:
So not to be an ahole but your description is off.
Grid-tied doesn't act as a gating mechanism as you imply.

A grid-tied inverter is in parallel to Eskom. Meaning if your inverter is supplying 2kW then it is adding 2kW to the grid.

If your demand is 3kW, that power isn't running through the inverter.
That is not true as you state it.
The inverter simply adds 2kW in parallel and the other 1kW will be sourced from Eskom.

The inverter adds more power to the power lines, at no point is all the power running through the inverter at a single point.

That is also why grid-tied cannot work if utility power is not available (IE> Eskom).
It isn't a source, it is a supplemental supply.

Axpert inverters on the other hand are UPS with a MPPT controller integrated allow some of the UPS power to come from Solar.
So it acts as a power source.

Completely different design
Click to expand...
We are on the same page, my description appeared off-putting but yes, the 2 work together, a grid tied system relies on Eskom at all times.
Excuse my way of putting it, not the same as yours.
 
Gnome said:
The inverter adds more power to the power lines, at no point is all the power running through the inverter at a single point.
Click to expand...
Now this part I did not know, I was under the impression that if you generate say 4kw and are consuming less than 4kw then you are off Eskom for that duration
 
I am confused here, if anyone with more knowledge can please share. :)
Is it true or false that if you generate say 4kw and are consuming less than 4kw that you will not be using Eskom power?
https://solaradvice.co.za/shop/solar-power/inverters/grid-tied-inverters/
from website it says: If the alternative power being produced is insufficient the deficit will be sourced from the electricity grid.
 
Grid-tied inverters are parallel.

sma-grid-tied.png


The inverter can supply up to its maximum rating to the grid.
If you need more power in your house than the inverter outputs, that extra power comes from the grid.
If you produce more power than is required by your house, it is exported to the grid.

I can't really explain it simpler than that.

Some "hybrid" inverters allow you to connect equipment to the inverter to prevent export to grid and it will only import from grid.

Really there is no easy way to explain this, you need to understand electric systems to understand these installations.

Axpert inverters are not grid-tied, they are closer to these "hybrid" systems. To use an Axpert you must connect the equipment downstream from the inverter.

But for grid-tied, you wouldn't need to do that, you connect it in parallel and your power usage will go down and your meter starts running backward when you produce more power than you need.
 
Then it is all exactly as I thought. Except for the part on Axpert not been grid-tied, I don't know their products at all.

I know about feeding back into the grid if your electricity meter is still the old analogue type, but Im not sure about feeding back into grid where it helps us. This is a dark topic that has little answers here in South Africa.

I know in USA you get credit when feeding back into the grid. From what I understand your meter can go backwards here but no credit as in money. Then again I am not 100% sure on this, would be interesting to hear from someone that has expereinced this.
 
Gnome said:
Grid-tied inverters are parallel.

sma-grid-tied.png


The inverter can supply up to its maximum rating to the grid.
If you need more power in your house than the inverter outputs, that extra power comes from the grid.
If you produce more power than is required by your house, it is exported to the grid.

I can't really explain it simpler than that.

Some "hybrid" inverters allow you to connect equipment to the inverter to prevent export to grid and it will only import from grid.

Really there is no easy way to explain this, you need to understand electric systems to understand these installations.

Axpert inverters are not grid-tied, they are closer to these "hybrid" systems. To use an Axpert you must connect the equipment downstream from the inverter.

But for grid-tied, you wouldn't need to do that, you connect it in parallel and your power usage will go down and your meter starts running backward when you produce more power than you need.
Click to expand...
I love SMA systems, I want to get the 3kw system in a few years time https://www.sustainable.co.za/sustainable-co-za-3kwp-grid-tied-system-solar-power-kit.html :)
 
Chuckmyster said:
Then it is all exactly as I thought. Except for the part on Axpert not been grid-tied, I don't know their products at all.

I know about feeding back into the grid if your electricity meter is still the old analogue type, but Im not sure about feeding back into grid where it helps us. This is a dark topic that has little answers here in South Africa.

I know in USA you get credit when feeding back into the grid. From what I understand your meter can go backwards here but no credit as in money. Then again I am not 100% sure on this, would be interesting to hear from someone that has expereinced this.
Click to expand...

From what I've heard is, the new digital type will turn off your power when that happens.
Unless you got one that allows it and word is they only install those if you register your system.
And when you register your system you need to pay a fee for the "privilege" to export power to the grid.

IIRC in Cape Town the fee is something like R400 a month just for the honor of exporting.
You also cannot earn money, you can only reduce your usage.

Overall unless you are on the old analogue meters I would say grid-tied for now in SA is not economical unless your monthly bill is crazy.

My monthly bill is like R300-400 so this whole fee is just going to make my situation worse.
As such I would do better with a downstream system that reduces my usage and doesn't export.

And I think most households probably fall into that category
 
Gnome said:
From what I've heard is, the new digital type will turn off your power when that happens.
Unless you got one that allows it and word is they only install those if you register your system.
And when you register your system you need to pay a fee for the "privilege" to export power to the grid.

IIRC in Cape Town the fee is something like R400 a month just for the honor of exporting.
You also cannot earn money, you can only reduce your usage.

Overall unless you are on the old analogue meters I would say grid-tied for now in SA is not economical unless your monthly bill is crazy.

My monthly bill is like R300-400 so this whole fee is just going to make my situation worse.
As such I would do better with a downstream system that reduces my usage and doesn't export.

And I think most households probably fall into that category
Click to expand...
mmmm that's great info
Yeah my bill is R350 a month but I want my geyser off the grid 1st.
I know it is cheaper and is more efficient to get the standard solar geyser systems everyone has but I want to go different as I fear having all that hot water on my roof and on a very hot day be at risk of a water burst.

https://www.sustainable.co.za/geyserwise-pv-solar-water-heating-kit-for-100l-geyser.html

Perfect for me as a bachelor - just a PV system running a 900w DC probe to warm the geyser for the once a day shower.

But yeah to invest in so much solar as you say is not worth it unless you have a big electricity bill
 
Gnome said:
Grid-tied inverters are parallel.

sma-grid-tied.png


The inverter can supply up to its maximum rating to the grid.
If you need more power in your house than the inverter outputs, that extra power comes from the grid.
If you produce more power than is required by your house, it is exported to the grid.

I can't really explain it simpler than that.

Some "hybrid" inverters allow you to connect equipment to the inverter to prevent export to grid and it will only import from grid.

Really there is no easy way to explain this, you need to understand electric systems to understand these installations.

Axpert inverters are not grid-tied, they are closer to these "hybrid" systems. To use an Axpert you must connect the equipment downstream from the inverter.

But for grid-tied, you wouldn't need to do that, you connect it in parallel and your power usage will go down and your meter starts running backward when you produce more power than you need.
Click to expand...


Thank you very much for the detailed explanation. I was always under the impression that grid power ran straight into the inverter. But in this sense, how do the appliances know to take inverter power over grid power if they bother running in a parallel?
 
calypso said:
Thank you very much for the detailed explanation. I was always under the impression that grid power ran straight into the inverter. But in this sense, how do the appliances know to take inverter power over grid power if they bother running in a parallel?
Click to expand...
Let's say electricity is water.
And I get some of my water from my solar water generator.
How much water I get from the "water grid" is determined by a meter.
Also let's assume the water is identical between the two.
Does it matter which one it "came from".
 
using the water analogy above, a Meter cannot determine which amount / percentage comes from the Eskom grid and how much from the solar panels - it would be the job of a Valve or Tap to do that.

The question is: if I consume 4kW, would 2kW (exactly half) come from the Eskom grid and 2kW from the solar panels (this would imply a Parallel connection);

…or would the algorithm in the inverter’s program know to use all it can from your solar panels, say 3kW (save maybe a pre-determined amount to trickle charge the Lithium cells), and therefore only draw the shortfall (around 1kW) from the Eskom grid ?
 
Space said:
using the water analogy above, a Meter cannot determine which amount / percentage comes from the Eskom grid and how much from the solar panels - it would be the job of a Valve or Tap to do that.

The question is: if I consume 4kW, would 2kW (exactly half) come from the Eskom grid and 2kW from the solar panels (this would imply a Parallel connection);

…or would the algorithm in the inverter’s program know to use all it can from your solar panels, say 3kW (save maybe a pre-determined amount to trickle charge the Lithium cells), and therefore only draw the shortfall (around 1kW) from the Eskom grid ?
Click to expand...
I think the most stable supply will lead the way, and that's Eskom AC, at the end of the day it is a parallel connection as you say, AC is most consistent and will simply reduce as the AC from solar comes in. I don't think there a complicated algorithm, it's the principle of demand and supply.
 
Takealot is selling a 5.5kW Axpert-type inverter today for R10 000

Not sure whether this one has the programs discussed above allowing you to:

1) draw your max requirement from your solar panels and only get any shortfall from the Eskom grid, therefore realising a large saving on your monthly Eskom/municipal consumption, or

2) choose to use it as a UPS during loadshedding, keeping as many of your devices running as possible with power from the solar panels & Lithium cells combined for the 2-4 hours that there is no grid power, or

3) while there is grid power to choose to re-charge your Lithium cells either from solar, or from grid (batteries only when dark, obviously), or both.


All I know is that 5.5kW inverters are usually upto 3 times this price.

Any opinions / comments / alternative suggestions from the experts ?


30118D53-9E8D-4654-9A91-B21A54DBD44F.jpeg
 
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