Converting 50kW system from micro inverters to 8x SMA inverters

[pclausen]

I had the devs that do the SMA integration for HA add the Isolation Resistance sensor to their integration and I was able to incorporate that into my solar dashboard:



Since the default threshold is 500 kOhm, and the max reading is 3 MOhm, I set the threshold to 16% (where the red turns green).

I'll probably do a time graph as well to track how the value changes for each inverter during the day, but this will do for now.

August was pretty cloudy this year, but I did manage to break 350 kWh a day once: (I had to restore from backup on 8/8, so I lost a day of data)



So I'm easily producing more power that I consume for my mining operation this time of year: (I had an issue mid week with the BrulTech GEM collecting power consumption from the mining rigs, normally they are all at around 200 kWh daily)



I'm overall very pleased with the conversion from micro inverters to string inverters so far and it feels good to know that all panels are operational.

[oregon_phil]

Thanks for the very complete build history and Home Assistant screen shots. I have HA, but have nowhere near your level of devices. I only have one SMA inverter and I don't mine, however. That makes it much easier for me to display data.

[pclausen]

Got a new toy:







Man, that 225A breaker sure gets hot with 200+ Amps passing through it. So does the 300 MCM copper table.

Its not quite as bad on the other end of the 300 MCM where it terminates at the meter base:

[pclausen]

Yesterday afternoon I got pretty close to the 600V DC input limit the SBs with 16 panels in series per string:



13 Volts to spare. We had a power outage that lasted from around noon until 4pm. I made a note to myself that if we get another power outage like that when its really cold outside, I'll turn off the DC disconnects on the SBs. That said, when the grid is down, nothing it being "inverted" to AC, so I don't know if that means the SBs would be ok if the DC input went above 600V?

[Ampster]

........We had a power outage that lasted from around noon until 4pm. I made a note to myself that if we get another power outage like that when its really cold outside, I'll turn off the DC disconnects on the SBs. That said, when the grid is down, nothing it being "inverted" to AC, so I don't know if that means the SBs would be ok if the DC input went above 600V?

That is probably a safe strategy in cold weather. I do not know the internal electronics of the SB's but high voltage could damage the MPPT section of the device even if the inverter is not running and no current is flowing.