How To Determine If The Potential Sensor Or Id Sensor Is Defective - Ricoh A66 Service Manual

HOW TO DETERMINE IF THE POTENTIAL SENSOR OR ID SENSOR IS DEFECTIVE

2. HOW TO DETERMINE IF THE POTENTIAL
SENSOR OR ID SENSOR IS DEFECTIVE
Purpose
When an image problem occurs, it is difficult to recognize whether there is a
problem with these sensors with only the SP data print out.
Measuring the signal coming into the main control board can help you to
recognize the defective part.
Overview
•
Ensure the resistance of the drum surface and the grounding wire.
•
Check the potential sensor and ID sensor output.
Condition
1. Image density is slightly high, but there are no other image problems.
2. The following SP values are out of the normal range for each color by
about the same amount.
SP No.
3-121
3-902
3. The Vmin display (SP3-910) value for each color is similar.
The value for Bk should be different from the color value.
(Normal condition*: Bk ≅ 0.03, Color ≅ 1.80)
* : These values come from a test machine, therefore the values are just
reference data and might not suit your machine.
A166/A187/A189
Normal condition*
K: 2.7 ~ 3.3
Color: 2.5 ~ 3.0
10 ~ 5
6-34 SM