Chapter 22-122.3.2.2 Ink Tank Unit2.3.2.2.1 Structure of Ink Tank Unit0012-6329a) Ink tanksThe ink level in each ink tank is memorized in EEPROM attached to the tank and is detected as a dot count on the basis of the EEPROM information.When an electrode attached to a hollow needle detects no continuity, it displays a message reporting that the ink tank is nearly empty.If the dot count reaches a predesigned value in this state, an ink out condition is assumed.b) Ink portDepressing the ink tank fixer lever on the printer would cause would cause a hollow needle to pierce the ink tank port sealed by a rubber plug, linking the ink passageof the ink to the printer.c) Air passageDepressing the ink tank fixer lever on the printer would cause an open hollow needle to pierce the air passage sealed by a rubber plug releasing the internal pressureof the ink tank to keep it constant.d) Notches for preventing incorrect installationInk tanks are furnished with a notch for preventing incorrect installation.If the installation of an ink tank in incorrect position is attempted, the notch would interfere with it, preventing its installation.The ink tank fixer lever won't lower without the ink tank fully inserted to reach the mounting position, so the ink cannot be supplied.F-2-9Ink tankInk portAir passageNotch for preventing incorrect installationEEPROMNotch for preventingincorrect installation