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10A 30V programmable supply: https://www.digikey.ca/en/products/detail/b-k-precision/9103/7056819
We have one of these in the bay already. We could get more if we want to test series MPPTs. There are cheaper options for power supplies in this range, but they are not certified (we tried to get a KORAD 30V 30A unit previously but they wouldn’t let us keep it).
Diode string - 30 of these in series should be reasonable: https://www.digikey.ca/en/products/detail/vishay-general-semiconductor-diodes-division/VS-E4TU2006FP-N3/8269295
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