Tektronix PHASER 380, Service Manual

Page: 229 / 346

Service Manual 8-23
Field Replaceable Unit Disassembly/Assembly
8
Drum position sensor assembly
Note A replacement sensor assembly must be precisely reinstalled on the
drum shaft in the position of the original sensor assembly. This
ensures that the stripper fingers contact the drum in the same location
as before; otherwise, serious print artifacts will result.
1. Turn off the printer and remove the power cord.
2. Remove the left -side cover as explained in the earlier topic, “Cabinet
panels and covers” on page 8-4.
3. Remove the plastic dust cover from the drum position assembly.
4. Disconnect the drum home-position sensor wiring harness from J105
(RED) of I/O board 1. Disconnect the drum position encoder sensor’s
wiring harness (locking style) at the drum position assembly.
5. Precisely mark the end of the drum shaft relative to the drum home
flag on the drum position sensor assembly as shown in the illustration;
use a straight edge to ensure accuracy; this is not necessary if you are
also replacing the drum (as part of the drum/transfix assembly).
6. With a small, flatblade screwdriver, slide the retaining spring out of
the encoder wheel’s groove toward the encoder disk; this removes the
tension securing the encoder wheel to the drum shaft.
Tools required
■
Magnetic screwdriver
■
#2 Phillips tip
■
Drum encoder wheel gap tool
Figure 8-16 Marking the drum-to-drum home flag sensor alignment
Drum home
flag
Drum position
encoder wheel
Mark on the drum shaft to
align with the home flag
9661-18