Control By The Cleaner Thermistor; Copying Speed Down Sequence - Canon NP7160 Service Manual

CHAPTER 4 IMAGE FORMATION SYSTEM
E. Control by the Cleaner Thermistor
The copier is equipped with a thermistor (cleaner thermistor TH3) used to detect overheating
of the drum cleaner assembly, and is designed to perform the following according to the
temperature detected by the thermistor.
• controlling the rotation of the exhaust fan (See p. 7-2.)
• controlling the copying speed down sequence
The cleaner thermistor checks for overheating of the drum cleaner at all times, and will
indicate error code 'E821' on the control panel when it identifies a temperature of 55°C or more.

1. Copying Speed Down Sequence

The copier's normal copying speed is 16 cpm (A4, Direct, non-AE).
To prevent overheating of the drum cleaner assembly in continuous copying mode or
overheating of the copyboard glass in enlargement mode, the copier adjusts the sheet-to-sheet
distance according to the selected copy count and the reading of the cleaner thermistor (TH3).
• A4 Original, A4 Copy
Reading by cleaner
thermistor (TH3)
Less than 40 C
40 C or more
4–20
COPYRIGHT © 1998 CANON INC.
Copy count at lower than 500
50 to100% 101 to141%
16cpm 12cpm
16cpm 12cpm
Table 4-202
CANON NP7161/NP7160 REV.0 AUG. 1998 PRINTED IN JAPAN (IMPRIME AU JAPON)
Copy count at 500 or more
142 to200% 50 to100%
12cpm 12cpm
8cpm 12cpm
101 to141% 142 to200%
12cpm 12cpm
12cpm 8cpm