Epson Stylus PRO Color Large Format Inkjet Printer 7000 Service Manual page 68

EPSON Stylus Pro 7000
Cover open sensor
To ensure proper paper feeding and to prevent paper jams, the front cover
must be closed during printing. There is one cover-open sensor that detects
when the cover is open using an interlock switch, and this sensor is located
near the left side of the main printer opening. When the cover is open, the
relay that controls the current to the CR motor and PF motor cuts off the flow
of that current. When this happens, the motors lose their electromagnetized
state.
Control
panel
Cover open
flag
Cover
Ink cartridge
holder
Figure 2-15. Cover Open Sensor
The sudden loss of current to the motors can cause problems and may even
damage the motors or the printhead. To prevent this, a discharge from the
capacitor connected to the current circuit is used to slow down the current
before it is totally cut off. This process ensures that printing stops when the
cover is open without causing any damage to printer parts.
Operating Principles
Cover open sensor
Cover open
sensor flag
Description of Components
CR
Driver
Motor
PF
Motor
Driver
Figure 2-16. Cover-Open-Motor Control Circuit
Revision B
Front cover
open
C126/127
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