Sounds like you are on the other side of the lake from me.
thanks for the reply's ,... so I gather from this that it is possible for 24V panel to produce 44V open circuit?
Yes. Maybe a bit more.
I tested 36 cell PVs at over 22Voc when it was not even cold.
And I had some GE or BP panels with 40 cells, so they would/could have been (40/36*>22Vov =) over 25V, which would make 2 of those in series, or a 24V version, over 50Voc.
I believe good quality controllers are either designed to handle this, or give detailed data sheets explaining why they can not.
Just a bit of current flow drops Voc a huge percentage. It would not be hard to make something to deal with wasting a bit of current at a certain voltage, which would drop the "apparent Voc" greatly.
Pull a vary small fraction of the rated amps out, and the Voc will drop like a rock.
Some 1W Zeners and a few 1W resistors would do it? Maybe?
G-