HP HPE StoreOnce 3100 Series Maintenance And Service Manual page 63

9. Disconnect the following cables from the backplane:
Number Cable
1 Front UID health module
2 Fan control card
3 Fan control card
4 Rear UID health module
5 Power distribution unit
6 Rear UID health module
7 Power supply
8 Power supply
10. Remove the eight drive cage retaining screws. There are four to a side.
NOTE: The StoreOnce System has 12 hard disks and the screws are in the 12LFF HDD
Cage location.
Removing and replacing the enclosure backplane 63