Epson EL 3S/33 - Manual (Page 73)

Connecting the Drive and Power Cables
To connect the drive to the computer, you need to connect both
the drive ribbon cable and a power supply cable. Follow the
steps below.
1. If you are installing a diskette drive, locate the diskette drive
ribbon cable. The middle of the cable is connected to the
system board.
If you are installing a second diskette drive, one end of
the cable is connected to the bottom diskette drive. The
cable contains both a card-edge connector and a header
connector.
4-14 Installing and
Removing Drives