TM 5-6675-324-14
(1) Delay jam. If the copy paper does not reach the detection sensor at the
outlet area within 272 pulses following the generation of the RGP signal, it is
judged that a delay jam has occurred. Thus, PDP1 = O represents jamming while
PDP1 = 1 represents normal copy delivery.
(2) Stationary jam at outlet area. If the correct number of delay jam
detection pulses has been generated, no delay jam has occurred. However, if the
copy paper has not completely passed the sensor of the detector at the outlet, a
stationary jam has occurred at the outlet. PDP1 = 1 indicates there is a jam,
whereas PDP1 = O represents normal copy delivery. When a sheet of paper is jammed,
the microcomputer emits the JAMRD command. (Q203-25 = 1.) The contacts of latching
relay K202 close to flash the JAM indicator LED602. The fuser heater control
circuit is activated to switch heater H2 off. Simultaneously, when the multiplexer
inputs Q205-3 = O and microcomputer Q203-3 outputs the strobe, Q205-12 generates O
and inputs it to microcomputer Q203-38, which prevents operation of the copier. To
reset, raising the release handle on the upper assembly changes jam reset switch MS3
to NC from NO. The latching relay K202 is reset by JRST2 = 1 (+24 V), applied to it
through D405 and R404 to open the contacts. At the same time Q215 is turned on and
JAM indicator LED602 flashes, LED602 will go off if door switches MS1 and MS2 are
actuated by lifting the upper assembly or opening the front door. If the power
switch is off, latching relay K202 will be reset by the discharge of C401 and C402
through the reset coil. When the upper assembly is closed after jam clearance, the
door switches are actuated to supply power to the dc controller. MS3 switches on to
set Q205-3 and Q203-38 to 1. Now copying can be resumed. When the upper assembly
is not closed properly, Q215 goes on because the NC contact of MS3 is closed, which
results in JAM indicator LED602 flashing and Q203-38 being O.
h. Paper/cassette out Indicator Circuit. Cassette sizes are detected by
microswitches MS4 and MS5. When a cassette is placed in the cassette holder, the C
(common) contact of one or both microswitches changes to the NO contact from the NC
to set the output of buffer Q250 to 1, which then will be input to the multiplexer
Q205. Paper supply detection lamp LA2 lights simultaneously. If there is no paper
in the cassette, light from LA2 shines on CdS1 and lowers its resistance, PEP = O,
Q213-4 = 1, and LED205 is on. Q216 grounds the output of buffers Q250-11 and Q250-
13 regardless of the actual buffer outputs. Since the outputs of Q250 are tied to
Q204-3 = 1, Q206-3 = 1, and Q206-13 = O, and PAPER/CASSETTE OUT indicator LED603
flashes, VR202 is the sensor adjustment.
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