Epson Stylus Color 980 Service Manual page 101

EPSON Stylus Color 980
Among the steps, if you do not perform Step 1 to Step 4 in the correct
order especially, Ink Cartridge Out error (Ink End error) may occur
whenever you replace the printhead. The background of this problem is
as follows.
1. Since the printhead equipped with this printer is composed of 480
nozzles and driven by 32.4 KHz, the temperature inside the
printhead rises more easily than any other printer. Therefore, the
temperatures inside the printhead and on the printhead board must
be intensely monitored to avoid damaging the printhead.
2. Rise in the internal temperature of the printhead can cause a fatal
damage to the printhead itself. Heat inside the printhead is normally
removed as the ink flows inside the printhead.
3. If any of the following conditions occurs, the printhead fails to eject
ink properly even though the print data is input.
The printhead surface is left away from the home position for a
long period of time.
The same ink cartridge is remove and installed repeatedly.
The table with the printer on it is moved up and down (vertically)
intensely.
4. If the ink does not flow properly, the PZT gradually heats up and is
eventually hot enough to evaporate the ink inside the cavity (a tank
which stores ink).
5. To prevent the printhead from heating up, the 5-channel abnormal
temperature detection circuit is included in the nozzle selector
(directly attached onto the printhead board). With this circuit, the
temperature of each nozzle row (five rows in total) can be
independently monitored. (Refer to Chapter 2 / Section 2.3.2.)
Troubleshooting
6. Once the abnormal temperature detection circuit is active, the
printer stops printing and starts a forcible cleaning. This operation
cleans the clogged nozzles, and the ink inside the printhead flow
properly as a result. At this point, the printer sets the flag in the
address for the abnormal temperature detection circuit in the
EEPROM to record the first abnormal temperature error.
7. The printer resumes printing with the data transferred.
8. If the printer detects an abnormally high temperature again, the
printer regards it as the second abnormal temperature error and
enters Ink End Error condition. The printer makes this judgement to
avoid following two problems:
Since the I/C has been repeatedly removed and reinstalled, the
printer fails to evaluate the remaining ink level properly and
leaves the I/C in an empty condition.
Since the I/C has been repeatedly removed and reinstalled, the
ink inside gets stale and can not absorb bubbles and viscous ink
into itself.
9. specifically, the nozzle selectors (5 rows in total) used in the mass
produced Stylus Color 980 are purchased from either of the
following two vendors: EPSON or Sharp. Their ICs slightly differ in
the feed back voltage. Therefore, if the installed printhead has the
nozzle selector and the 1st digit of the printhead ID in the
combination shown in Table 3-35, the printer shows the error at
power on and begins a cleaning automatically. Therefore, even
though the printer continues to print, it forcibly enters the Ink End
error condition for the second time since the flag is already set in the
EEPROM address for the abnormal temperature detection circuit.
Overview
Revision A
97