MPP 10K 3phase is the right for me ?

curto

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Guys,

We are in Australia and are looking to replace our current small 3kw solar system.

We have 3 phase to our house and a number of 3 phase appliances so i would like to go 3 phase hybrid.

We currently use an Electricity provider Amber Electric - they pass through whole sale rates to us - which can fluctuate wildly dependant on load on the grid etc. at rhe most extreme in the evenings the price per Kw/h can go to $16 - however - the FIT rate for solar at that time is also very high.

They have an API that i am using in Node-red to access their forecast data on a sliding 12 hour window.

I intend to implement a battery system (i am not that DIY on hardware so will probably end up buying a packaged system) and want to be able to do the following

1) Command the inverter to not feed to the grid at all (in the case of negative FIT) when excess energy is in the grid
2) If execess energy on the grid and there is a negative FIT - command the inverter to charge the battery from the grid (rather than solar)
3) If FIT rates are high then command the inverter to push xKW from the battery bank to the Grid (whilst still powering the house)

I have seen many of the more mainstream inverters that can do some of these - but the only one i have found so far that appears to do them all is the GoodWe ET series - however i am waiting on information as to whether if can be controlled programmatically rather than having to use an app/web interface to set schedules (which will not work as the rates and times are variable)

I have then come across this forum and the SIS project and this seems very promising - i am just wondeirng if the ability to control the inverter has been published and/or documented somewhere - rather than just monitoring the data coming from the inverter.

I have sent an email to australian distributor - not sure how helpful they will be at this point.

Craig
 
Hey
Im the one behind sis.

The MPP work "Kind of like you want but not all the way".
Let me explain

MPP MPI:
* It have an idle consumption of around 240w. ANd total per day calculate 7kWh losses....
* 1 year warranty only
* its 10kW MAX... Nothing else. I e 3.3kW per phase no matter is max
* You can only controll sending back with around 1kW per phase max in manuall mode and max 1time per second can this be changed though it looks up easy so every 3-4 seconds is best
* If you want full 0-meter function and feedback with more than 1kW from battery you need to use automatic mode with an SDM630.. BUT you cannot controll this behavious at all or see it in their api.

So is this inverter the right for you? I wouldnt say so if you looked at alot more expensive ones. I think Victron or other are better. But yes the mpi can kind of work for you. If you need more info i can help you with it. But beware that their software on those inverters are buggy.
And yes there is just a mention in the code that you can do it. Same as in the docs for the protocol. I have had to guess and figure it out...


The GoodWee operates with high voltage batteries....
 
daromer said:
Hey
Im the one behind sis.

The MPP work "Kind of like you want but not all the way".
Let me explain

MPP MPI:
* It have an idle consumption of around 240w. ANd total per day calculate 7kWh losses....
* 1 year warranty only
* its 10kW MAX... Nothing else. I e 3.3kW per phase no matter is max
* You can only controll sending back with around 1kW per phase max in manuall mode and max 1time per second can this be changed though it looks up easy so every 3-4 seconds is best
* If you want full 0-meter function and feedback with more than 1kW from battery you need to use automatic mode with an SDM630.. BUT you cannot controll this behavious at all or see it in their api.

So is this inverter the right for you? I wouldnt say so if you looked at alot more expensive ones. I think Victron or other are better. But yes the mpi can kind of work for you. If you need more info i can help you with it. But beware that their software on those inverters are buggy.
And yes there is just a mention in the code that you can do it. Same as in the docs for the protocol. I have had to guess and figure it out...



The GoodWee operates with high voltage batteries....
Daromer,

Thanks for taking the time to respond and coming back so quickly.

I thought the warranrty looked strange when everyone else was doing 5 or 10 years - the Australian distributor offers and option to extend it by 3 year for another $350

Thats a lot of energy that is wastes 240w every hour just sitting there - what is it doing to use that much energy ?

I would not need to change the settings more than once every 5 minutes or so i think

Is the 1Kw per phase on the grid output purely from the battery bank or is that also from Solar ? Seems a very strange and arbitrary limit to set - any idea why they did that ?

Can you turn manual and automation mode on and off from the API ? i. infer from the way that you said it - that in automatic mode the unit will be able to push more current out to the grid ?

Our energy meters are all net at meter across phases - so does not really matter from that point of view. I thought the SDM630 was single phase only - does it need one on each phase ? to get true Zero watt ?

I assume i can charge the battery from the grid under API control ?

Can you point me to the Doco so i can read up on the API and what is there ?

I have started digging through your SIS project and looks good so far - but what i have seen so far - all appears to be Reading only ?

Craig
 
240w reffers to roughly 80w per phase and is quite standard on cheaper equipment in this genre.

Yes warranty out of the box is 1 year and some dealers add to it for a HIGH cost.

1kw dont know why. Never got their answers on that... No you cannot switch between their built in automatic and this way. There is no way to internally see that the inverter even talks to the SDM630 unless they released a new firmware i havent seen.
I tested it and 999 was max :)

SDM630 is pure 3phase. The MPI is also 3 phases in one unit. therefore max 3.3kW per phase is the limit in the software. So its not 10kw total....

Its a common bidirectional bus. So yes Solar > battery > grid is possible in all scenarios

You can charge from grid and turn it on and off via its api BUT its very weird and you need to change mode when doing it so its not in battery mode any more. So it will switch its internal relays.....

You have the protocol in the solar-sis

Yes 99% is reading since most people dont know how to do writing to it and its pretty sensitive.
You can find examples of the r/s/t phases and how i set them there. You can also read through the raspbery solar thread where i have added some examples how its done.
No its not very good documented :) Feel free to document or help out :)
 
Ok thanks Daniel.

Lets say i do this another way as i am resigned to the fact that i can not find a 10KW 3 phase inverter with battery output that will let me do what i want.

Instead if i buy a cheap 10KW 3phase inverter and just use that to feed my solar into my house - i already have an IOTAWat on the way so i will be able to measure everything i need in terms of power draw from the grid, power input from the solar and power useage in the house so i should be able to automate everything i want that way

I then buy a reasonable Battery monitor/charger/inverter that i can programatically control for the batteries i.e.

So i would want to charge the batteries at X KWs, discharge them (into the grid) at X Kws etc

What would you recommend for that charger/inverter for 3 phase ? for a LV battery connection with say a max output of 8kw from the batteries

Craig
 
I have found your raspberry thread also am reading my way through that for all the info and background i can get on the mpp units

regards

Craig
 
I havent scounted all the genre on what can do this. But many Hybrid systems can. Victron you can build your own setup with the components needed.
Beware of that transfering energy from AC to Battery back to AC isnt the cheapest on 48V systems since you have some losses there. Just an FIY :)
 
daromer said:
I havent scounted all the genre on what can do this. But many Hybrid systems can. Victron you can build your own setup with the components needed.
Beware of that transfering energy from AC to Battery back to AC isnt the cheapest on 48V systems since you have some losses there. Just an FIY :)

OK thanks Daromer.

Just out of interest how does the MPP know how much power i am using - presumably it has some form of clamp or Power meter it interfaces to ? If so - does it do that through RS485 or Modbus over TCPIP ? If it was either it might be possible to hack it and sit in between and then lie to the inverter about how much power the house is using so it pushes out more when i want to dump my batteries to the grid ?

I just had this thught last night and was going to start doing some research on it
Craig
 
When using the 0meter system you hook up an SDM630 meter and buy their modbus card.. If it actually works and what not i dont know. Since you cannot see it in the interface nor configure it i ditched it. Their support could not even tell how its supposed to work

But there are people using it... Black Magic?
 
daromer said:
When using the 0meter system you hook up an SDM630 meter and buy their modbus card.. If it actually works and what not i dont know. Since you cannot see it in the interface nor configure it i ditched it. Their support could not even tell how its supposed to work

But there are people using it... Black Magic?
HMm,

I was under the impression this was what fedback to the inverter how much power was needed for the load when you it in the mode of Solar, Battery, Grid - maybe i have got that wrong

Unless is has some form of active energy monitoring i do not understand how it would know when to kick your batteries in to supplement solar and reduce imports from the grid ?
Craig
 
Normal hybrid will kick ALL energy that are excess to the grid. Thats how grid-tie works

Solar > battery > grid.
On your load side thats where you use the priority

If you want 0 meter you need to add a meter on the outside as described. Otherwise it wont work. Using the Load port is something else.
 
Wow... that's a lot more idel current than I though, but its still a good value if you are not limited by panels I have limited space so my array is not that large.

I was thinking of getting a LC2424 off grid model for emergency power its single phase over here. Does that mean I wont see more than 80 watts idle current?
 
The 2424 is alot lower Idle consumption. Perhaps 20w or so?
 
In Australia you do NOT need to go 3 phase for
Your solar system or battery system even if you have 3 phase power. We bill differently to many other countries.

You can for example run a 10kw appliance on L1, have a 5kw solar system on L2 - feeding back 100% to the grid and your only billed the difference (5kw)

So, to make things simple, go single phase.


If you want local info Ive done a bit of research and can help.
 
slimf said:
In Australia you do NOT need to go 3 phase for
Your solar system or battery system even if you have 3 phase power. We bill differently to many other countries.

You can for example run a 10kw appliance on L1, have a 5kw solar system on L2 - feeding back 100% to the grid and your only billed the difference (5kw)

So, to make things simple, go single phase.


If you want local info Ive done a bit of research and can help.



Yep i was aware of that thanks - BUT we are limited to a max feed in on 5KW to the grid on any single phase - so if i go for a single phase battery then i will be limited to a max of 5KW - i am also yet to find any single phase battery that will supply more than 5KW AT ONCE (some peak to about 7.5Kw). Then finally we have the issue of powering the house in the event of a blackout.

Craig
 
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