Page Length Measurement - Epson LX-300 Service Manual

EPSON LX-300+
RPE DETECTOR
RPE detector is installed on the paper path at the back of the printer. The table
below shows the RPE detector specifications.
Table 2-11. RPE Detector Specifications
Item
Method
Switching rate
Switching mode
BPE DETECTOR
BPE detector is installed right under the platen. The table below shows the
BPE detector specifications.
Table 2-12. BPE Detector Specifications
Item
Method Mechanical contact method
Switching rate 0.6 to 1.0 mA, 5 VD±5%
• Paper inside: open
Switching mode
• No paper: close
Operating Principles
Specification
Mechanical contact method
0.6 to 1.0 mA, 5 VD±5%
• Paper inside: open
• No paper: close
Specification
Printer Mechanism (M-3M10)

2.2.5.1 Page Length Measurement

Page length measurement is a process to convert the following value to the
number of printing lines.
Value = [The number of paper feed pulse from the paper top (top margin:
4.2mm) until RPE detector detects paper end] + [forms over-ride specified
paper feed pulse] - [adjustment value]
When CSF is used:
The uncertainty of the paper end detector may vary the number of
printing lines within the same paper size. To avoid this, when CSF is
used, page length measurement calculates the printable lines and if
the paper is longer than the printable lines, the number of printing
line is considered the printable lines (fixed value).
When paper is shorter than the printable lines, the printer prints the
fixed number of lines by forms over-ride function (which allows the
fixed number of lines to be printed even when RPE detector detects
paper end).
When CSF is not used:
When loading paper manually or when tractor feed is used, the
number of printing lines of paper end is determined by forms over-
ride function after BPE or RPE detector detects paper end.
Revision A
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