Toner End Detection
Toner near-end is detected by the toner end sensor [A], which is located be-
low the toner tank.
While the main motor is rotating, the machine detects toner end by the volt-
age output from the toner end sensor . The voltage from the sensor is close
to 5 V when the toner tank is full and becomes low when toner is almost
empty.
Toner near-end condition: When the cpu detects a low output from the
toner end sensor for more than 30 s, the cpu starts to blink the Add Toner indi-
cator. This is the toner near-end condition.
Toner end condition: After toner near-end is detected, the machine can
print 100 more sheets, then the cpu disables printing (this is the toner end
condition).
The machine clears the toner near-end or toner end condition when the
power is switched off and back on or when the cover is opened and closed, if
the output from the toner end sensor goes back high again.
However, when the machine is turned off/on or when the cover is opened and
then closed, the machine requires about 30 s to check for a toner near-end
condition again. So, if the user prints something within this 30 s period with-
out changing the CTM, the machine will allow the printout to be made, but the
print quality may be poor.
[A]
H521D624.wmf
Toner Tank
Toner End Sensor
FDU
FCE
CPU
1-90
7-10
7-9
5V
H521D660.wmf
DETAILED SECTION DESCRIPTIONS
May 22nd, 1995
PRINTING
2-32