Duct Jam Sensor Adjustment - Ricoh DD 4450 Service Manual

Master Feed

4.7.7 DUCT JAM SENSOR ADJUSTMENT

Ensures that the sensor detects when a master remains in the duct.
Standard: 0.5 volts (within "+0.1" and "-0.1"volts)
Tools: Circuit tester
Rear cover ( p.4-10 "Rear Cover")

1. Check if a master remains in the duct. If a master remains in the duct, remove the master
from the duct.
2. Connect the terminals of a circuit tester to TP102 and a grounded place (e.g. iron base)
3. Connect the power plug, and turn on the main switch to access SP mode.
4. Select SP6-52 (Duct jam sensor voltage).
5. Press the Print Start key.
6. Measure the voltage with the circuit tester, and turn VR102 until the value becomes between
"-0.1" and "+0.1" volts from the standard value (0.5 volts)
When the voltage cannot be adjusted to the standard value, adjust the threshold level of

the duct jam sensor. (SP6-52: Duct jam sensor voltage)
Standard Value
Master present
Above 2.0V
C279
Threshold level (SP6-52)
2.0V
4-44
Standard Value
Master not present
0.5 +-0.1V
SM