Adj 9.1 Developer Spacing - Xerox Phaser 790 Service Manual

Adjustment
1. Calculate the difference between the average measured value and the nominal values as
displayed in the Table 1.
2. Calculate the required adjustment value, allowing 1 unit increment to equal 0.17 mm of
change in top-to-bottom registration, or 0.50 mm of change in side-to-side registration.
3. Prepare to adjust the printer registration.
a. Enter the Diagnostic Mode (IOT) (GP 1).
b. Press the Menu button until IOT PARAM SET is displayed.
c. Press the Item Enter button.
d. Press the Up Arrow or Down Arrow button until CTRL VAL SET is displayed, then
press the Item Enter button.
e. Using the Up Arrow and Down Arrow buttons, select the Menu Number from the
Table 2.
f. Press the Item Enter button to display the current value of that parameter.
g. Using the Up Arrow and Down Arrow buttons, change the value as required.
h. Press the Item Enter button to write the new value.
i. Scroll the menu until DIAG EXIT is displayed, then press the Item Enter button.
j. Wait until the message PLEASE POWER OFF is displayed and then switch off and
switch on the power.
4. Perform the check again.
Table 2 Printer Registration Items for the Parameters
Menu No. Function
11 Side-To-Side Registration
Adj Range 127 min-0-128 max
16 Top-To-Bottom (Tray 1)
17 Top-To-Bottom (Tray 2)
18 Top-To-Bottom (Tray 3)
19 Top-To-Bottom (Bypass Tray)
1A Top-To-Bottom (Duplex Tray)
NOTE:
Menu item 11, Side-to-side registration range of adjustment is approximately 25mm. The
adjustment producing the image shift towards the lead edge is referred to as the minimum
value of 127. Decreasing the value to zero causes the image to shift away from the lead
edge. An adjustment from 0 to 255 is a single .10mm increment. Further adjustments from
255 through 128 continues to shift the image further from the lead edge. An adjustment to
128 provides the furthest image shift away from the lead edge. Selecting value 127 produces
a huge change in image position, with the image shifted to being nearest the lead edge.
Repairs and Adjustments
ADJ 8.1, ADJ 9.1
Default Maximum Minimum
Value Value Value Unit
201 128 127 0.10 mm
30 64 0 0.17 mm
37 64 0 0.17 mm
35 64 0 0.17 mm
28 64 0 0.17 mm
17 64 0 0.17 mm

ADJ 9.1 Developer Spacing

Purpose
The purpose is to ensure that the Developer Housing is at the correct distance from the Copy/
Print Cartridge.
Check
To avoid personal injury or shock, do not perform repair activities with the power switch
on or electrical power applied to the machine.
1. Switch off the machine power and disconnect the machine Power Cord.
2. Remove the Top Cover Assembly (REP 14.4).
3. Release the Rotary Latch. Turn the Rotary Frame clockwise until the magnetic roll of the
target Developer Housing is at the top. Continue to turn until the Rotary Latch catches in
the notch of the Rotary Frame.
Do not touch the surface (surface around circumference) of the white tracking roll with your fin-
gers while performing the following step. If you accidentally touch the surface of the tracking
roll with your fingers or if oily substances get on the surface, wipe the roll clean with a clean
cloth.
4. Clean the White Tracking Roll in front of the target Developer Assembly (in front of the
Magnetic Roll) with a clean cloth (Figure 1).
5. Make a mark on the White Tracking Roll, at the edge of the White Seal, in front of the tar-
get Developer Assembly (in front of the Magnetic Roll).
If a mark already exists on the White Tracking Roll, rotate the roll to align the mark with
the edge of the White Seal (Figure 1).
Turn the Rotary Frame as slowly as possible while performing the following step. Turning the
Rotary Frame too fast will produce a discrepancy in the amount of position change, thus mak-
ing it impossible to get an accurate reading. Visually inspect to make sure the black drum
flange and tracking roll touch each other while turning.
If you do not raise the lever of the Rotary Latch in the following step, the lever and tracking roll
will touch. This will allow the tracking roll to turn and you will not be able to accurately deter-
mine the amount of position change.
NOTE: The tracking roll is rotated when the black drum flange and tracking roll touch in the fol-
lowing step of the procedure.
6. Release the Rotary Latch which prevents the Developer Housing from turning. Turn the
Rotary Frame as slowly as possible 360 degrees (clockwise). This will allow you to mea-
sure how much the position has changed by how far the mark has moved from the edge
of the White Seal.
7. Check the Developer Spacing (Figure 1).
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WARNING
CAUTION
CAUTION
Phaser 790/DocuColor 2006
Initial Issue