I gave it a thought
Conclusions and solutions I found so far,
Yes your installer is right, you want to export through orion, that's not possible
He's not topi baaz as you were assuming, he's right
At a time only huawei can export or orion
Both can't, unless 2 inverters are same and paired in parallel configuration (which is not the case in our situation, so forget export from orion as for now)
Right now your problem is backup, we will address that
1st solution, highly recommended, opt for it on 1st priority if it suits you
rough Wiring diagram for simplification
In this case
Ac grid with Bi directional meter will remain connected with huawei, and huawei will export and import
You have 31 panels
We will make 2 strings
String 1, 19 panels, same as old configuration, as it is, will remain connected to huawei
String no 2, 12 panels, with a changeover, changeover output will be connected to huawei and orion
Hence we can control 6.5kw pv input from your existing system, will be used as PV input for huawei and solar max orion depending upon, whether grid is available or not
When it's available, with huawei so that huawei can export excess,
When grid is off, then with orion so that you can run load on PV and batteries
Then, how to manage load? And ac input for solar max orion?
huawei AC output will be connected with orion, orion will use huawei output as grid that incase your panels are generating during day, huawei will power solar max orion and orion will charge your batteries, orion will assume that you're using grid to charge batteries, but actually those are panels charging batteries during day through orion, hence will do the job (just set time in orion and turn off charging during peak hours in orion settings)
And then same output wire from huawei will be connected to changeover, alongside orion output,
So when utility is available
You can use huawei output, full 15kw
When there's no grid, you can run load thorugh orion, during day on pv, during night on batteries, but keep that in mind, it's 6 kw inverter, don't put load beyond that
Why I didn't recommend adding panels to orion?
Answer is, that doesn't makes sense, you have 17kw pv input already, you can utilize the current setup efficiently during load shedding in daytime rather than adding more panels
Right now, during daytime if you are already wasting a lot of units because of load shedding, but with orion, you have 6.5kw pv input for generation, hence 2x of the panels you wanted to buy, those units produced by panels during daytime by 6.5kw input will simply compensate for separate 3kw pv input
When both changeovers are on 1, you will be using 17kw on grid system
When both changeovers are on 2, you will get 6.5kw hybrid system
PS: I'm not a professional, discuss this with your installer 1st then proceed
If there's any flaw in wiring etc then mention
