Hi,
How does the MPPT RS measure insulation resistance?
I often see the insulation resistance values fluctuate when the string voltage is still changing significantly: in the morning during start-up, or in the evening just before switching off.
Even without any sun: often 100 MΩ — but then it sometimes drops to 50 MΩ, only to slowly rise back to 100 MΩ…
So I’m interested in how the measurement is carried out internally, to understand what’s going on.
Best regards,
Broesel