8 hours ago, Steve87 said:

Now, I love the quality the Sunsynk & the Deye have brought to the market. However, if a product doesn't meet you needs then you have the wrong product. @MKRandburghas a very specific requirement with what she wants to achieve. The Sunsynk I'm afraid does not meet that requirement. 

Further to the point, having played around In both the residential & commercial solar markets I can safely say that the Grid Tied architecture of the Sunsynk or Deye makes sense for the Commercial world & for one reason only. High constant loads. Makro & other large commercial institutions, the grid tied arrangement makes sense. They want to pay as little to Eskom as possible. The have a massive PV arrays on the car parks/ Car ports & these Grid tied Solar Edge inverters push as much energy as possible from the PV against the Grid so they pay as less as possible. 

When it loadsheds, the PV inverters turn off. It's a legal requirement. These machines are Grid interactive. The Sunsynk does the same, however, with a difference. It as they say a "True Hybrid" it can also have backup power via the battery. However, you only backup the Essential loads. Correct me if I am wrong @Sc00bsin this scenario, you cannot feed PV power to the non-essentials like the geyser???

At night with no PV you cannot serve the non-essentials with power from the battery but only from the GRID. In essence it loadsheds & you stuck with the essential loads on that battery. 

 

@Steve87 I think that you are looking at having the essential/non-essential loads ports as a disadvantage, There is no requirement to have your heavy loads attached to the non-essential side of the Sunsynk inverters. It is just an easy way for people to disconnect their heavy loads without having to either automate their disconnects using smart switches etc or run around switching geysers etc off manually.

The main thing on the Sunsynk's is that you do not want to be going over the maximum pass thru current limit on the inverter or the inverter will trip out to protect the relays in the inverter that switch between grid attached and island mode. Max continuous pass thru  on the 5kw is 35A which @ 230V is about 8kw, on the 8kw is 50A or about 11.5kw. So as long as you manage your loads to keep them under those limits you won't have any problems and can connect what you like. I have 4 geysers, a borehole pump, a 1kw pool pump and a pressure pump all connected to the essential side of my inverter. They are however all on automated smart switches and don't all try to run at the same time.  Having the loads and the non-essential connection moves them to the other side of the relay so when they are using power it isn't passing thru the relay, as you said thought the downside/advantage of having it connected this way is that they are not connected when there is load shedding.  

On the AXpert inverters I would imagine (please confirm) that you either have to have your heavy loads wired in before the inverter, in which case you cannot back feed them power at all or stay under the maximum power of the inverter in total and have to switch them off either with a smart switch or manually at night.

@Steve87 @BritishRacingGreen Can one of you confirm what happens if you exceed the maximum load on the Kodak/Axpert inverter, does it switch the load back to the grid or does it trip out? Alkso, can you confirm if when it is working in "Blended" mode, it is powering the inverters transformer with power from the grid  rather than power from the PV's/Battery, there is an efficiency penalty that you pay because of this if it is doing it that way rather than working in a grid-tie mode. 

Finally, What are @MKRandburg requirements that the Sunsynk does not meet? I am unsure as to what it is that she wants to do that the AXpert inverters do but the Sunsynk doesn't?  

9 hours ago, Steve87 said:

Yes it will work without the Grid present & power loads directly from the Solar PV. It is not a Grid tied architecture like the Sunsynk/ Deye. It will output AC power directly from PV to the loads. If you exceed the loads, she will just power trip. But, the joy of this is that most essentials like a fridge etc are low powered so is you have a decent sized Array & just need some essentials like the fridge, WiFi, TV & some odds & ends you have some good free energy & without Eskom being involved. 

Thank @Steve87 I have definitely learnt something 🙂, is an interesting use case

36 minutes ago, Sc00bs said:

@Steve87 @BritishRacingGreen Can one of you confirm what happens if you exceed the maximum load on the Kodak/Axpert inverter, does it switch the load back to the grid or does it trip out? Alkso, can you confirm if when it is working in "Blended" mode, it is powering the inverters transformer with power from the grid  rather than power from the PV's/Battery, there is an efficiency penalty that you pay because of this if it is doing it that way rather than working in a grid-tie mode. 

Hi @Sc00bslong story short, it renders the machine in overload and trips. Of course this is one of the disadvantage of offgrid type machine. This is also the magic of gridtie, it will push whatever it has against even a 30kw grid demand. So offgrid machine will typically need to match the load demand. 

BUT... here is the reason why gridtie does not work for me :

Forgetting for a moment the essential circuit of the gridtie machine, cause thats an offgrid function in my books. The nonessential circuit is only optimum during sunny periods,cause no battery input is part of this transfer function. I have mostly energy usage at night and little at sun peak. Now one can argue to shift loads from essential to nonessential, but thats just approximating offgrid style of operation. 

So having smart load switches in order to timeshift the replenishment of energy during pv yield is what works for me, hence my desicion to go for offgrid inverter vs gridtie. 

 

It also allows me to use battery power at night for nonessentials if i so require.  In fact ihis is the major advantage of the offgrid configuration. 

 

 

Edited September 16, 20223 yr by BritishRacingGreen
Extra info

5 minutes ago, BritishRacingGreen said:

Hi @Sc00bslong story short, it renders the machine in overload and trips. Of course this is one of the disadvantage of offgrid type machine. This is also the magic of gridtie, it will push whatever it has against even a 30kw grid demand. So offgrid machine will typically need to match the load demand. 

BUT... here is the reason why gridtie does not work for me :

Forgetting for a moment the essential circuit of the gridtie machine, cause thats an offgrid function in my books. The essential circuit is only optimum during sunny periods,cause no battery input is part of this transfer function. I have mostly energy usage at night and little at sun peak. Now one can argue to shift loads from essential to nonessential, but thats just approximating offgrid style of operation. 

So having smart load switches in order to timeshift the replenishment of energy during pv yield is what works for me, hence my desicion to go for offgrid inverter vs gridtie. 

@BritishRacingGreen Pretty much the same situation as me, all my loads are "essential loads" and I time shift them with smart switches toi ensure that they aren't running at the same time.  I think that the main advantage of the Sunsynk over the AXpert inverters is that have a buffer that you can exceed the inverters maximum power output with.  My house is often running in the 7-7.5kw range when the geysers/pool/borehole etc are all running, if someone switches the kettle on, it doesn't trip the inverter out,  it just pulls the power over 8kw from the grid. As long as the load doesn't go over 11.5kw there is no problem. During load shedding I obviously have to stay under 8kw.  

53 minutes ago, Sc00bs said:

Finally, What are @MKRandburg requirements that the Sunsynk does not meet? I am unsure as to what it is that she wants to do that the AXpert inverters do but the Sunsynk doesn't?  

Run in battery independent mode. I have an existing generator. So back up power is not my main concern - it's a 2.2kva - I'm used to reducing my load during loadshedding. Daytime loadshedding without running the generator would be a win. I also have a limited budget and want to do a phased approach. Without requiring backup, I just cannot justify my limited budget going to batteries. 

Edited September 16, 20223 yr by MKRandburg
typo

28 minutes ago, Sc00bs said:

@BritishRacingGreen Pretty much the same situation as me, all my loads are "essential loads" and I time shift them with smart switches toi ensure that they aren't running at the same time.  I think that the main advantage of the Sunsynk over the AXpert inverters is that have a buffer that you can exceed the inverters maximum power output with.  My house is often running in the 7-7.5kw range when the geysers/pool/borehole etc are all running, if someone switches the kettle on, it doesn't trip the inverter out,  it just pulls the power over 8kw from the grid. As long as the load doesn't go over 11.5kw there is no problem. During load shedding I obviously have to stay under 8kw.  

8kw sunsynk is an obvious good choice, best of both worlds, but sadly, an item my budget wouldnt allow. 

56 minutes ago, BritishRacingGreen said:

So having smart load switches in order to timeshift the replenishment of energy during pv yield is what works for me, hence my desicion to go for offgrid inverter vs gridtie. 

@Sc00bs @BritishRacingGreen @Steve87
Off-grid and grid-tie and essentials and non-essentials confuse me. 

If I use the off-grid Kodak - I can put whatever power tools on and it won't affect the inverter right? If there is grid - not during loadshedding.

If I had the sunsynk - I would be limited to what power tools I put on because it needs to be limited to whatever the top value is for the 5kw or 8kw? Is this right? Unless I put the garage and stuff on nonessentials on the SunSynk - then it's not a problem. Because I'm not going to be using my table saw during loadshedding either but I might want to put my geyser on, and with the SunSynk, it gets tricky - you have to put stuff in aux or something? 

Just want to check if I'm understanding this now.

4 hours ago, BritishRacingGreen said:

MKS3 upwards employs both DC coupled and AC coupled (gridtie) techniques to affect seamless blending. The pv and battery are mixed at the DC stage, and when inverted from dc to ac, its ac coupled with the grid input for further blending.  So although gridtie technique is used, this is internal to the machine, outside of it there will be no export of grid like in true gridtie.

Yes, though they can't guarantee absolutely no export of energy. No control system is so good that it can pull back the inverter power instantly when a large AC load drops off. So a little energy gets burped into the AC-in port now and then. If you have enough non-essential loads, this won't even back-feed to the meter and grid. Hopefully, when the grid goes away with load shedding, a relay drops out internally and prevents back-feeding into the now-dead grid cables.

I don't know how they handle the situation where just your house gets dropped off the grid. If the inverter is feeding power into a load and happened not to need any grid power when the grid disconnects from your house, I don't see how it would know that the grid has gone, so that cable will still stay energised. Hopefully they have smarts similar to on-grid models to figure that out and be safe in all conditions. Usually, a whole area will go down at once, so even if there are many grid tie inverters supplying power at the time, they likely won't be able to power the whole area, so the grid voltage will collapse, and the inverter realises that the grid has dropped out, and all is safe.

4 hours ago, BritishRacingGreen said:

EDIT:  about a year ago there was some members that report inadvertent exporting of their Axperts, this was probably a firmware bug of sorts at the time. 

No, it's simply not possible to prevent exporting small bursts of energy when large loads drop off. The devil is in the detail of how well they handle the various conditions.

2 hours ago, MKRandburg said:

@Sc00bs @BritishRacingGreen @Steve87
Off-grid and grid-tie and essentials and non-essentials confuse me. 

If I use the off-grid Kodak - I can put whatever power tools on and it won't affect the inverter right? If there is grid - not during loadshedding.

If I had the sunsynk - I would be limited to what power tools I put on because it needs to be limited to whatever the top value is for the 5kw or 8kw? Is this right? Unless I put the garage and stuff on nonessentials on the SunSynk - then it's not a problem. Because I'm not going to be using my table saw during loadshedding either but I might want to put my geyser on, and with the SunSynk, it gets tricky - you have to put stuff in aux or something? 

Just want to check if I'm understanding this now.

Hi @MKRandburg

Not 100% correct, maybe  @Steve87 or @BritishRacingGreen can confirm on the Kodak info about going over the inverter power limits? 

My understanding is that if you use the Kodak and you go over the maximum power for the inverter for more than 5-10 seconds, it will trip and doesn't switch the supply to grid (the part I am not 100% sure of). So, if you have a 5kw and you go over 5kw for any extended period of time it will trip the inverter out. 

That is not the case with the Sunsynk inverters as they blend in power from the grid up to the maximum pass thru current. This gives you some extra headroom over the rated power of the inverter. There are still limits,  on the 5kw it is 35A or +-8kw load & on the 8kw the max load is 50A or +-11.5kw, that if exceeded will cause the inverter to trip out but there is some extra space there. 

You can also put whatever loads you want on the "Essential" side, it is purely for your convenience so that heavy load items, which are not essential to the house and which would kill your battery, are automatically disconnected when running without the grid. If you prefer you can manage the loads yourself and just need to make sure you don't go over the limits of the inverter production when there is no grid to give you that extra headroom.  

There are also settings on the inverter for the non-essential side to prioritise  battery charging for example over running devices on the non-essential side of the inverter. You can set a battery level to be attained before it will start running the  non-essential side of things from Solar.  

The only thing that I can see the Kodak doing that the Sunsynk can't do is run an AC supply from solar with no battery or grid, something for which although it would not be very reliable, it does have use case for it (powering a standard pool pump for example) 

The Kodak Inverter is also obviously cheaper as well. 

I would be interested to know what the efficiency of the AXPert inverters when running a load on the inverter being power purely by the grid. So say a 1kw load on the inverter, what is the load the inverter puts on the grid? Maybe someone with one could tell me 🙂 

3 hours ago, MKRandburg said:

@Sc00bs @BritishRacingGreen @Steve87
Off-grid and grid-tie and essentials and non-essentials confuse me. 

If I use the off-grid Kodak - I can put whatever power tools on and it won't affect the inverter right? If there is grid - not during loadshedding.

If I had the sunsynk - I would be limited to what power tools I put on because it needs to be limited to whatever the top value is for the 5kw or 8kw? Is this right? Unless I put the garage and stuff on nonessentials on the SunSynk - then it's not a problem. Because I'm not going to be using my table saw during loadshedding either but I might want to put my geyser on, and with the SunSynk, it gets tricky - you have to put stuff in aux or something? 

Just want to check if I'm understanding this now.

I'm am not so sure about putting on any power tool. The total load being fed from the off grid inverter is still dictated by the size of the inverter. A 7.2kw Kodak even it it blends with the grid cannot provide more than 7.2kW towards loads. You are in the same position as a Sunsynk when grid is off. When grid is on the Sunsynk can provide its size in power from inverter but the rest is drawn from the grid. So with Sunsynk the limit is your utility main MCB.

This is how I think it works?

2 minutes ago, Scorp007 said:

I'm am not so sure about putting on any power tool. The total load being fed from the off grid inverter is still dictated by the size of the inverter. A 7.2kw Kodak even it it blends with the grid cannot provide more than 7.2kW towards loads. You are in the same position as a Sunsynk when grid is off. When grid is on the Sunsynk can provide its size in power from inverter but the rest is drawn from the grid. So with Sunsynk the limit is your utility main MCB.

This is how I think it works?

100% right except you are limited to the maximum pass thru current on the essential connection on Sunsynk, not your MCB. 

There is no limit on the non-essential side as it is essentially a grid tie so the only power going through the port it power going out and there is no pass thru.

10 minutes ago, Sc00bs said:

100% right except you are limited to the maximum pass thru current on the essential connection on Sunsynk, not your MCB. 

There is no limit on the non-essential side as it is essentially a grid tie so the only power going through the port it power going out and there is no pass thru.

Thanks for pointing out. I thought the max from pass through is as per spec of about 50A on the 8kW. On the non essential side you can draw as much as you want to up to what the source(grid) can provide. Thus no limit. The only limit is what you can get from PV and battery towards non essential.

Edited September 16, 20223 yr by Scorp007

5 hours ago, Scorp007 said:

A 7.2kw Kodak even it it blends with the grid cannot provide more than 7.2kW towards loads.

It can, I am just not sure for how long before it trips. My inverter exceeded 7.2kW for 3-4 minutes and actually ran at 8.0kW for a few seconds. See below. Did not trip. 

Hi, I have installed many of these cbi switches... If it shows "offline" on your app then there is either no internet or there is no power... If your geyser is on your non essential side during loadshedding then your device will be offline. The automation side pretty good as you can make a lot of "if this" "then that" programs. Comes in handy when you want to control multiple devices during certain weather conditions or loadshedding. If you just want to use it to add a timer to your geyser then there are cheaper options

 

 

 

 

On 2022/09/15 at 7:39 AM, MKRandburg said:

I want to control the geyser from the CBI - I don't want to have to flip the geyser switch on the DB - my thinking was - set the app to not auto restart the CBI after outage. So after the power goes down, the CBI will be off, no wifi and no power. Flip the changeover to gennie, wifi comes back on but CBI remains off, therefore no geyser because the CBI is off. 

MKRandburg did you find the issue, was it just the device restart status that was set to ‘on’ like Don suggested?

 

I had almost a similar issue this morning, we had load-shedding so my essentials were al powered by inverter but my wife wanted to use the tumble dryer which is on non-essential, I have enough capacity for one big appliance at a time so I switched the non-essentials over to the inverter as well but soon the inverter tripped, thats when I realized my Astute’s for the geysers and the underfloor heating that is on non-essential side switched on directly when power up. It was on restart status ‘on’ I set it to ‘off’ and inverter was happy the rest of the day.

1 hour ago, Gerrie said:

MKRandburg did you find the issue, was it just the device restart status that was set to ‘on’ like Don suggested?

 

I had almost a similar issue this morning, we had load-shedding so my essentials were al powered by inverter but my wife wanted to use the tumble dryer which is on non-essential, I have enough capacity for one big appliance at a time so I switched the non-essentials over to the inverter as well but soon the inverter tripped, thats when I realized my Astute’s for the geysers and the underfloor heating that is on non-essential side switched on directly when power up. It was on restart status ‘on’ I set it to ‘off’ and inverter was happy the rest of the day.

I believe it must have been. I've got it set to restart status off now and haven't had an issue, so it must have been on default status on and I just didn't realise it. It's all good! 

On 2022/09/16 at 6:51 PM, Don said:

It can, I am just not sure for how long before it trips. My inverter exceeded 7.2kW for 3-4 minutes and actually ran at 8.0kW for a few seconds. See below. Did not trip. 

Thanks. This still does not proof that it is rated at more than 7.2kw. It must be able to do it for hours on end. 

The question was if one can put any load through the inverter without it tripping. It was in that context that I indicated it is rated at 7.2kW. Yes according to the specs it can provide 7.5kW for 5 min only.

8 hours ago, Scorp007 said:

This still does not proof that it is rated at more than 7.2kw.

No, it is not. It is rated at 7.2kW. It can handle 7.2kW continuously without a problem and even if you exceed this limit up to 8.0kW for a few seconds, the inverter will not trip. That is the only point I was trying to make. 

18 hours ago, FSS said:

Hi, I have installed many of these cbi switches... If it shows "offline" on your app then there is either no internet or there is no power... If your geyser is on your non essential side during loadshedding then your device will be offline. The automation side pretty good as you can make a lot of "if this" "then that" programs. Comes in handy when you want to control multiple devices during certain weather conditions or loadshedding. If you just want to use it to add a timer to your geyser then there are cheaper options

 

 

 

 

What are you using for the  "if this" "then that" programs?

On 2022/09/16 at 6:51 PM, Don said:

It can, I am just not sure for how long before it trips. My inverter exceeded 7.2kW for 3-4 minutes and actually ran at 8.0kW for a few seconds. See below. Did not trip. 

I think running at 8.0kW for 3-4 minutes is quite restrictive. Hmmm, I'm a little worried about this. I want to still be able to pull as much from the grid as I want. Is this because there are batteries? I just can't get my head around this aspect.

2 hours ago, MKRandburg said:

I think running at 8.0kW for 3-4 minutes is quite restrictive.

I am not sure I follow you. How can a 7.2kW inverter running at 8.0kW for a few minutes be restrictive? Why would you want to run an inverter 10% above its rated power? If you want to run at 8.0kW, buy a 10kW inverter or 2x5.0kW inverters in parallel. 

16 minutes ago, Don said:

I am not sure I follow you. How can a 7.2kW inverter running at 8.0kW for a few minutes be restrictive? Why would you want to run an inverter 10% above its rated power? If you want to run at 8.0kW, buy a 10kW inverter or 2x5.0kW inverters in parallel. 

Yes, this... exactly what you said. It was what I was trying to understand. I know it makes sense to you and is easy for you to understand but for some of us, we need a bit more of an explanation to understand. 

I was trying to understand what the impact of having my house going through the inverter - now I know. I don't want to be restricted by the inverter - so clearly need to move some of the house onto another part of the db, or get a bigger inverter, or understand my loads better and shift them. At the time of asking the question, I didn't understand this - so your answer didn't make sense. 

But thank you for responding and adding to my understanding.

On 2022/09/15 at 12:39 PM, MKRandburg said:

The Kodak OSG5.6 is an off-grid hybrid that blends power between Eskom and inverter. But does not require a battery, where the Sunsynk does need a battery. So the problem I have is that the Sunsynk isn't flexible enough for me.

I have a Sunsynk and for 4 weeks while my battery was in for repairs, the inverter worked just fine.  I just ticked the no battery option.  Solar was fine to power the house during the sunlight hours.

35 minutes ago, JayN said:

I have a Sunsynk and for 4 weeks while my battery was in for repairs, the inverter worked just fine.  I just ticked the no battery option.  Solar was fine to power the house during the sunlight hours.

Even when the grid was down? During loadshedding?

Interestingly, last night the power went off for loadshedding. CBI app has been set with restart status as OFF for sometime now. When the power came back on, I switched the gennie switchover to grid and the mains tripped. It tripped a few times until I switched the geyser breaker off  manually (not the CBI one). When I turned the geyser on via the app this morning, all was good. I'm not sure it's related but maybe it is... going to keep an eye on it.