Hi Arno,
Please refer to the cabling diagram of ML350 Gen9 which shows the cabling for the controllers in PCI slots to the FBWC module backup(Smart Storage Battery in this case) power cabling:-
https://support.hpe.com/hpesc/public/docDisplay?docId=emr_na-c05052722
In the above link refer to:-
FBWC module backup power cabling
Storage controller installed in slot 1 to 4
Storage controller installed in slot 6 to 9
Link also shows the cabling of the Smart storage battery to the systemboard.
So depending on which slot the controller is installed refer to the cabling diagram
Hope this answers your query.
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