Epson LQ-2550 User Manual page 34

1. Plug the connector of the cable securely into the printer.
WARNING: Do not plug more than one interface cable
into the printer at one time. This may damage the printer.
2. Using a screwdriver, secure the connector by tightening the screw on
each side of the connector.
Note: If the screws that come with the cable do not fit into the
connector lock nuts on the interface, you need to replace these lock
nuts with the optional lock nuts provided with the printer.
Setting Up the Printer 1-25