4.6
IMAGE DENSITY SENSOR BIAS
The ID sensor bias is similar to the development bias; however, it is applied
only when developing the ID sensor pattern.
Basically, the ID sensor bias is fixed. The normal ID bias level is --240 volts,
but it can be changed using service program #18. The following table shows
the possible settings. You should clearly understand the effect of changing
the ID sensor bias. If the ID sensor bias is increased the sensor pattern will
become lighter. This will cause more toner to be added to the developer and
thus copy images will become darker and toner consumption will increase. If
the ID sensor bias is decreased, lighter images and less toner consumption
will result.
Service Program #18
Setting
0
1
2
3
ID Bias
--240
--200
--280
--320
Factory Setting
A developer counter correction is applied to the ID sensor bias to compensate
for changes in the triboelectric properties of the developer as a new developer
mixture is broken in. The following table shows this correction. Notice that the
correction depends on the average Vsp/Vsg ratio as measured during initial
conditioning as well as on the developer counter. By factoring in the initial
conditioning Vsp/Vsg ratio, this correction compensates for slight variations
between different lots of developer as well as for changes in the developer
during the break-in period. After the initial conditioning, the copy counter will
display the density level (dL).
Developer Counter Correction
dL
Initial Conditioning
Vsp/Vsg
Developer Counter
0--499 Copies 500--999 Copies More than 1000
1
0--10
--40 V
--20 V
0 V
2
10--15
--20 V
0 V
0 V
0
15--20
0 V
0 V
0 V
3
20--25
+20 V
+20 V
+20 V
4
>25
+40 V
+40 V
+40 V
NOTE: Perform the initial conditioning by SP#5 whenever the developer
mixture is replaced. Do not perform SP#5 when the drum is replaced.
There is a possibility of dLE being displayed. This means that there
was on ID sensor (Photo sensor) error during the initial conditioning.
6 January 1990
2-25
Содержание FW 810
Страница 1: ...SECTION 1 OVERALL MACHINE INFORMATION...
Страница 22: ...SECTION 2 DETAILED SECTION DESCRIPTIONS...
Страница 73: ...SECTION 3 INSTALLATION...
Страница 88: ...SECTION 4 SERVICE TABLES...
Страница 122: ...SECTION 5 REPLACEMENT AND ADJUSTMENT...
Страница 152: ...5 Clean the toner overflow sensor E with a blower brush or equiva lent E 6 January 1990 5 30...
