Reading data from other SP pro units

[potatothesparky]

Hi, great code, thanks for the efforts, I've adapted it to my needs but I've run into a problem.

The site I'm working on has 3 SP pro units, one per phase when reading the memory register 0xa3a8 it only returns data from the inverter connected to phase L1, do you have any information of how to change to L2 and L3 units or what the memory locations are to read their data.

Alternatively can you point me in the direction of how I might go about finding this out?

[neerolyte]

Hey, interesting problem. I haven't got access to a system with multiple phases. For context I'm not a sparky, just an off gridder who happens to also be a software engineer.

The first thing I would try is looking through a decompiled copy of SPLink for terms like "powerchain", "phase" etc. I don't have a copy hanging around at the moment and I'm flat out for a while so probably won't get to that this week or next.

It's pretty incomplete but starting a selpi proxy with debug logging selpi --log=debug proxy and then connecting through that proxy with SPLink should dump the raw protocol to the console. It can be pretty hard to untangle though, I think ideally it'd dump a pcap and then I'd add support to libpcap to decode it in Wireshark.

P.s if you have a preferred use case, let me know what it is so I can try not to break it. I've been thinking about rejigging this to mostly just expose Prometheus style metrics as I just want a fast metric source to graph/alert on and also to integrate an OpenEVSE with.

[potatothesparky]

Hey, thanks for your thoughts and suggestions.

My background is electrician specialising in systems integration and automation. Although software development is not my core work its often just writing a script here and there to read and write data. I'm alright with Python, albeit no expert but for this use case I was cherry picking the parts of your code I needed and rewriting the functions into Lua which is the native language used by this particular sites automation controller.

I took your suggestion and decompiled SPLink, I've attached the entire memory map for future reference.

For what its worth I was only after two additional parts, the total solar generation by all inverters and the grid export/import power as this is a grid tied installation, I didn't investigate getting the data from each inverter seperately, although I'm sure it is there somewhere.

The two memory locations of interest for me were below. Interestingly enough the ACGeneratorPower is either a diesel generator, or the grid, depending on the installation conditions, in some installation conditions it can be both if you are grid tied with generator backup.

AddQuickView_TotalKacoAcPower = 41199;
AddQuickView_ACGeneratorPower = 41193;

Prometheus metrics would be suitable, gives options and flexibility for grafana, etc.
For me I think it won't be very likely I'll come across another customer that has a Selectronic installation requiring integration. All the other major inverter/charger manufacturers just publish a REST API or support Modbus over TCP with supporting documentation so its usually rather straight forward.

Selectronic SPLink memory map.txt