Sunsynk Hybrid with other inverter acting as gris supply?

[Northern Optimist]

Does anyone know if I can use a smaller inverter, instead of the grid through the grid port. Got 8kw Sunsynk Hybrid with matching array and battery bank. All currently off grid. Aquired additional grid tie inverter with its own smaller array. I think I can connect this as an input to the Aux port if I check the specs of the new one, but I would like to keep that free for output to the heat pump. So, can I connect it to the grid port, leaving the smaller unit with the only grid tie and the auxilliary port still outputting? Would really appreciate your input. Thanks

 

[timselectric]

Grid-tied inverters require a "grid source" to operate.
They won't turn on without it, for safety reasons.

 

[houseofancients]

Grid-tied inverters require a "grid source" to operate.
They won't turn on without it, for safety reasons.

Does anyone know if I can use a smaller inverter, instead of the grid through the grid port. Got 8kw Sunsynk Hybrid with matching array and battery bank. All currently off grid. Aquired additional grid tie inverter with its own smaller array. I think I can connect this as an input to the Aux port if I check the specs of the new one, but I would like to keep that free for output to the heat pump. So, can I connect it to the grid port, leaving the smaller unit with the only grid tie and the auxilliary port still outputting? Would really appreciate your input. Thanks

Add another sunsynk ( deye/sol-ark) would very much be preferred..
If you need to add a grid-tie inverter ( i.e. ) you need to connect it to the aux ( smart port) to create a mini grid, controlled by here's.

If you connect any but the grid ( or generator) , both you new inverter and sunsynk will not work , as the sunsynk will simply shutdown the grid port

 

[houseofancients]

To add, your heatpump should be connected to the non-essential side of things ( i.e. grid port)
Controlling heatpumps by an aux port is an extremely bad idea, and inefficient at that

Smart ports ( or aux) can be used for electric waterheating elements, or pumps, that again are non-essential.

I am guessing you need the head pump for heating your home..
Usually when that is needed, there isn't much sun, so it will simply not run

 

[Northern Optimist]

Ok seems I have somehow mislead you a little. We currently have an 8kw array with 30kw batteries. With half that storage capacity we got through last winter and this grey summer completely disconnected from the grid. We only used the aux power supply to keep the batteries heated inside their winter cubicle. We did go back on grid very briefly due to manufacturer faults being fixed. As you will no doubt know, some of the coldest days (ie clear and freezing with snow on the ground produced as well as mid summer) The heat pump is a new addition and was bundled with the extra array and grid tie inverter. The heat pump is feeding a heat store supported by a wood stove back boiler using wood from our own managed woodland. If we use the Aux port for the heat pump and set it to run when batteries above 60%, we should still have more power left for the rest of the house than we had last year..Especially with the extra power from the new array. Aux port can be used for output or input upto 4kw, but not both. The Sunsynk inverter runs quite happily off grid. Obviously the grid tie inverter will need to remain connected to the grid.We will use grid tie for export only, mainly during summer months until we find a use for the extra power generated at this time. So my question is I guess, does the grid port know it's power supply is not coming from the grid, but another inverter with it's own grid tie. Is there something unique about the Aux port that makes it ok to get supply this way, but not the grid port.

 

[houseofancients]

Ok seems I have somehow mislead you a little. We currently have an 8kw array with 30kw batteries. With half that storage capacity we got through last winter and this grey summer completely disconnected from the grid. We only used the aux power supply to keep the batteries heated inside their winter cubicle. We did go back on grid very briefly due to manufacturer faults being fixed. As you will no doubt know, some of the coldest days (ie clear and freezing with snow on the ground produced as well as mid summer) The heat pump is a new addition and was bundled with the extra array and grid tie inverter. The heat pump is feeding a heat store supported by a wood stove back boiler using wood from our own managed woodland. If we use the Aux port for the heat pump and set it to run when batteries above 60%, we should still have more power left for the rest of the house than we had last year..Especially with the extra power from the new array. Aux port can be used for output or input upto 4kw, but not both. The Sunsynk inverter runs quite happily off grid. Obviously the grid tie inverter will need to remain connected to the grid.We will use grid tie for export only, mainly during summer months until we find a use for the extra power generated at this time. So my question is I guess, does the grid port know it's power supply is not coming from the grid, but another inverter with it's own grid tie. Is there something unique about the Aux port that makes it ok to get supply this way, but not the grid port.

Did you check the startup amps of your heatpump ?

Just to add, have almost the same setup as you, just more batteries and bigger inverters ( 2*12k 3 phase sunsynk), and a heatpump.

Unless you put something like a microwave ( or similar Schneider inrush limiter) , or a true inverter heatpump, the compressor startup will get you far over 4 kw

 

[timselectric]

So my question is I guess, does the grid port know it's power supply is not coming from the grid, but another inverter with it's own grid tie. Is there something unique about the Aux port that makes it ok to get supply this way, but not the grid port.

Ok, I think that I understand what you are trying to do.
You can connect the grid-tied inverter in front of the SunSink hybrid. (Between the grid and SunSink)
And this will work as long as the grid is on. Both the grid and grid-tied inverter will provide power to the SunSink grid port.
If the grid is down or turned off. The grid-tied inverter will shutdown and the SunSink will continue to provide power to its loads. If your heat pump is connected ahead of the SunSink. It will only have power when the grid is up/on. Powered by the grid and/or grid-tied inverter.

 

[Northern Optimist]

Did you check the startup amps of your heatpump ?

Just to add, have almost the same setup as you, just more batteries and bigger inverters ( 2*12k 3 phase sunsynk), and a heatpump.

Unless you put something like a microwave ( or similar Schneider inrush limiter) , or a true inverter heatpump, the compressor startup will get you far over 4 kw

Thanks. That makes sense, but I'm not sure Aux output is limitted. I thought it was just input. I will try and check. Plus if I'm using Aux for output and Grid port for input, perhaps the 4kw doesn't apply?

 

[Northern Optimist]

Thanks. That makes sense, but I'm not sure Aux output is limitted. I thought it was just input. I will try and check. Plus if I'm using Aux for output and Grid port for input, perhaps the 4kw doesn't apply?

Extra info from Sunsynk- the grid port can also be used for a generator if not on the grid so perhaps another inverter supply is also possible?

 

[Northern Optimist]

Ok, I think that I understand what you are trying to do.
You can connect the grid-tied inverter in front of the SunSink hybrid. (Between the grid and SunSink)
And this will work as long as the grid is on. Both the grid and grid-tied inverter will provide power to the SunSink grid port.
If the grid is down or turned off. The grid-tied inverter will shutdown and the SunSink will continue to provide power to its loads. If your heat pump is connected ahead of the SunSink. It will only have power when the grid is up/on. Powered by the grid and/or grid-tied inverter.

Close. hat's really helpful, but I'm looking for the holy grail and ideally don't want anything powered by the grid (ever) . As we are now, before the heat pump installation. I might see if my supplier can give me an off grid inverter instead as the feed in pay back isn't likely to be more than £600p/a and we're looking to expand our activities to use the extra free electric in the summer months and maybe even charge a vehicle.

Did you check the startup amps of your heatpump ?

Just to add, have almost the same setup as you, just more batteries and bigger inverters ( 2*12k 3 phase sunsynk), and a heatpump.

Unless you put something like a microwave ( or similar Schneider inrush limiter) , or a true inverter heatpump, the compressor startup will get you far over 4 kw

It seems only input through Aux port is limitted to 4kw. Output can go to 8.8kw. which I hope and am checking is sufficient for Aerona 3 R32 heat pump startup. If so and it looks like I can connect other grid tie or off grid inverter to the grid port, all is hunky dory.

 

[timselectric]

Just an FYI,
Anything you connect to the grid port. Will need to be AC coupling capable. Otherwise you will fry it ,if you send power to its output.

 

[houseofancients]

Just an FYI,
Anything you connect to the grid port. Will need to be AC coupling capable. Otherwise you will fry it ,if you send power to its output.

And to add, anything AC coupling capable ( including the sunsynk grid port) will not work if there is no grid, as the sync to the grid feature, and if that is not there the islanding is activate..

So your choice here is on of 3
1 connect second sunsynk and do it properly
2 connect some sort of other hybrid and risk frying everything
3 connect micro inverters/grid tie inverter without grid, nothing will work...

 

[timselectric]

And to add, anything AC coupling capable ( including the sunsynk grid port) will not work if there is no grid, as the sync to the grid feature, and if that is not there the islanding is activate..

It would have to be a hybrid AIO. It would have to form a micro grid and accept AC coupling.
But this is also problematic, when it's batteries get full.

 

[Atetra]

And to add, anything AC coupling capable ( including the sunsynk grid port) will not work if there is no grid, as the sync to the grid feature, and if that is not there the islanding is activate..

So your choice here is on of 3
1 connect second sunsynk and do it properly
2 connect some sort of other hybrid and risk frying everything
3 connect micro inverters/grid tie inverter without grid, nothing will work...

Are you sure about this? From my understanding the sunsynk with batteries simulates a grid so the micro or string inverters will work because as far as they are concerned there is a grid! I think what you described only happens when you are running a system without batteries. The scenario where I believe you would be correct if if his batteries are dead in which case his system would be down.

I have seen a few setups like this including Andy’s garage where he uses a phoenix inverter as an AC feed into his multiplus. There is also a video on YouTube where Keith of sunsynk says while it is ideal to ac Couple via the aux port for max control, you dont Have to, just that the sunsynk won’t have control over the micro inverter.
From my understanding so long as the micro/string inverters see a grid, they will work. They don’t know if it is your mini grid or the national grid.

 

[houseofancients]

Are you sure about this? From my understanding the sunsynk with batteries simulates a grid so the micro or string inverters will work because as far as they are concerned there is a grid! I think what you described only happens when you are running a system without batteries. The scenario where I believe you would be correct if if his batteries are dead in which case his system would be down.

I have seen a few setups like this including Andy’s garage where he uses a phoenix inverter as an AC feed into his multiplus. There is also a video on YouTube where Keith of sunsynk says while it is ideal to ac Couple via the aux port for max control, you dont Have to, just that the sunsynk won’t have control over the micro inverter.
From my understanding so long as the micro/string inverters see a grid, they will work. They don’t know if it is your mini grid or the national grid.

are you sure you want to blow up your expensive sunsynk, because that is what will happen if there is inflow of power on the load port

Keith is mentioning connecting both sunsynk and micro inverters to the grid in port, which requires a grid connection, but won't work if there is no grid ...

grid failure/off grid = loss of power from both microinverters and sunsynk
be smart, do it the way it is supposed to be done

 

[Atetra]

are you sure you want to blow up your expensive sunsynk, because that is what will happen if there is inflow of power on the load port

Keith is mentioning connecting both sunsynk and micro inverters to the grid in port, which requires a grid connection, but won't work if there is no grid ...

grid failure/off grid = loss of power from both microinverters and sunsynk
be smart, do it the way it is supposed to be done

What I am questioning here is your assertion that

grid failure/off grid = loss of power from both microinverters and sunsynk

..and I am saying that conceptually and from evidence from others on YouTube and systems I have witnessed myself physically you are wrong.

The microinverters are designed to shut down if there is no grid, I agree that’s how they are designed to work but what I am saying having witnessed this myself is that if thre is another system that can provide a “grid” e.g a hybrid inverter with batteries simulating a grid the micro or string inverters will continue to work.

I have physically witnessed a system with AC coupled fronious string inverters and Victron Quattro with battery back up in total off-grid mode. It works there is no grid connection in that installation. If the batteries get depleted the system shuts down as there is no “grid” and then they need a diesel generator to recharge the batteries to “wake up” the grid and then the AC coupled fronius will come alive again if there is sun.

again I gave the example of andy of off grid garage, he is also off grid, not only is he using a phoenix inverter to simulate generator AC power into his multiplus when he needs a boost but he also has microinverters with frequency shift control via his multiplus. His system is off grid hence the name of his channel.

finally conceptually the micro inverter or string inverter needs to see a grid to work. it does not know if the grid it sees is utility grid or a micro-grid. AC power is AC power and so long as the voltage and frequency is within spec and ther is sun it will come on.

edit: and no neither will the sunsynk shut down, the only difference between off grid and on grid is with off grid you can frequency shift your AC coupled inverters with the sunsynk so long as they are connected to the aux port whereas on grid you cannot. In the instance I gave in my initial post (Keith) where the AC coupled inverter were not connected via the aux port, then on or off grid you cannot control the micro or string inverter because but they will still work

 

[houseofancients]

What I am questioning here is your assertion that

..and I am saying that conceptually and from evidence from others on YouTube and systems I have witnessed myself physically you are wrong.

The microinverters are designed to shut down if there is no grid, I agree that’s how they are designed to work but what I am saying having witnessed this myself is that if thre is another system that can provide a “grid” e.g a hybrid inverter with batteries simulating a grid the micro or string inverters will continue to work.

I have physically witnessed a system with AC coupled fronious string inverters and Victron Quattro with battery back up in total off-grid mode. It works there is no grid connection in that installation. If the batteries get depleted the system shuts down as there is no “grid” and then they need a diesel generator to recharge the batteries to “wake up” the grid and then the AC coupled fronius will come alive again if there is sun.

again I gave the example of andy of off grid garage, he is also off grid, not only is he using a phoenix inverter to simulate generator AC power into his multiplus when he needs a boost but he also has microinverters with frequency shift control via his multiplus. His system is off grid hence the name of his channel.

finally conceptually the micro inverter or string inverter needs to see a grid to work. it does not know if the grid it sees is utility grid or a micro-grid. AC power is AC power and so long as the voltage and frequency is within spec and ther is sun it will come on.

edit: and no neither will the sunsynk shut down, the only difference between off grid and on grid is with off grid you can frequency shift your AC coupled inverters with the sunsynk so long as they are connected to the aux port whereas on grid you cannot. In the instance I gave in my initial post (Keith) where the AC coupled inverter were not connected via the aux port, then on or off grid you cannot control the micro or string inverter because but they will still work

we are talking about deye/sunsynk/sol-ark here, not victron ....
you asked a question, you got an answer, do whatever you like with it

 

[Atetra]

we are talking about deye/sunsynk/sol-ark here, not victron ....
you asked a question, you got an answer, do whatever you like with it

You made a generic claim about off grid and AC coupling with hybrid inverters, I countered it.

having said that it is the same principle at play with the Victron, they are both biderctional inverters, you could say Deye/sunsynk were designed to offer the functionalities of Victron sat a cheaper price point. furthermore these issues are well documented by Keith the owner of Susnsynk. You can watch the videos where he talks about it. If I have a minute I will post the videos. There are even official videos from Deye which illustrate AC coupling when the grid goes down.

1:02 grid goes down, micro inverter still working

 

[houseofancients]

You made a generic claim about off grid and AC coupling with hybrid inverters, I countered it.

having said that it is the same principle at play with the Victron, they are both biderctional inverters, you could say Deye/sunsynk were designed to offer the functionalities of Victron sat a cheaper price point. furthermore these issues are well documented by Keith the owner of Susnsynk. You can watch the videos where he talks about it. If I have a minute I will post the videos. There are even official videos from Deye which illustrate AC coupling when the grid goes down.

you are missing the point of the different in and output ports of the sunsynk...

i highly suggest you look at the manual, the installer courses again...

there is 1 bidirectional port on these inverters : the grid port...
the grid port senses the availability of the grid, is that not there , it will shut down

there is a load port that will keep working in a grid down situation, but this cannot handle incoming flow of power

there is an aux / smart port which can be programmed to be either an output port ( smart) or an input port, not both

you should connect you micro inverters to the aux port, so that the inverter can control them based on frequency and so they will not shutdown when there is no grid.

this mostly comes down to you not having a clue how these devices work

 

[Atetra]

you are missing the point of the different in and output ports of the sunsynk...

i highly suggest you look at the manual, the installer courses again...

there is 1 bidirectional port on these inverters : the grid port...
the grid port senses the availability of the grid, is that not there , it will shut down

there is a load port that will keep working in a grid down situation, but this cannot handle incoming flow of power

there is an aux / smart port which can be programmed to be either an output port ( smart) or an input port, not both

you should connect you micro inverters to the aux port, so that the inverter can control them based on frequency and so they will not shutdown when there is no grid.

this mostly comes down to you not having a clue how these devices work

See video above