Epson Stylus Photo R320 Printer Basics Manual page 54

7. Lower the cartridge into the holder, with the green circuit board facing the front. Then
gently push the cartridge down until it clicks into place.
8. If you need to replace another ink cartridge, repeat steps 5 through 7 before continuing
with step 9.
9. Close the ink cartridge cover.
10. Press
OK
The printer begins charging the ink delivery system.
11. When you see a message that charging is complete (after about a minute), press
54
Maintaining Your Printer
and close the printer cover.
.
OK