Migration strategy


I will soon install a second PV system. I have studied the data aggregation section in the wiki but I’m not sure as to how to proceed.

Current system: system A
New system: system B
New parent system: C

I would like to achieve the following:

  1. reuse the name of the current system A as the name for the new parent system C
  2. create a new child system with all the data from the current system A
  3. create a new child system B
  4. aggregate all data to the new parent C without loosing any data from system A

My concern is that if I start experimenting I may loose data. Is the above possible and if so what are the steps I need to take?


Note that Data Aggregation only affects live data from the time it is enabled - i.e. historic data won’t be copied from the children to the parent.


That is certainly useful (even essential) to know but can you spell out the steps required to meet my requirements?


There are two options, both don’t involve data aggregation.

  1. Create new System B and start uploading to B. Existing System A will still have its data.
  2. Update existing System A details to match that of new install, upload to this system.

Data aggregation is more suited for combining multiple inverters or consumption + generation scenarios.


Thank you. If I understand this correctly, System A will become the parent, keeping all legacy data and aggregating new data from System B, System B will become the current system with data from its creation time onward and I will have to create a new child, System C for the new inverter.

Did I get this right?


System A will keep its historic data. By making A the parent of B, any new live data added to B will be copied to A.

Note that the kWh/kW figures on A will be incorrect for the data copied from B, as the sizes of the old and new system will be different.

System C won’t be necessary unless you wish to combine B and C to A.


Sorry for not getting this. I’m not going to replace the current system (A) with a new system B. I’m adding a new system B. I need to aggregate both the current A and the new B into the parent C. I get the impression that your answers assume that I’m replacing A with B.
Summary (without referring to any letter names):

  • current system (need to preserve historic data)
  • new system (will start uploading new data)
  • new parent system (needs to show aggregated data, including historic data)


Aggregation only works on new live data - the new parent system will not have any historic data, only the combined live data of any children assigned to it.