NCR 7156, Руководство по обслуживанию, Страница: 143 / 206

7156 Service Guide Chapter 14: Replacing the Print Mechanism
September 1998 129
You must use three extender cables (available in a kit) to connect the following three cables
to the common PC board:
•
MICR Read Head Cable
•
MICR Buckhead Cable
•
MICR Solenoid Cable
Note: In addition, a longer cable for the front LED sensor is included in the kit to replace
the current cable which is not long enough to connect to the new common PC board.
See “Appendix C: Common PC Board and Extender Cables” for more information about
the extender cables. See the Parts Information Manual for the kit number.
Caution: Electro Static Discharge may damage the MICR amplifier board. Wear a
grounded wrist strap and use a static mat or other ESD protected work surface whenever
you work with the MICR amplifier board.
1. Route the motor harness from the paper feed motor through the two cord keeps on the
right side of the base as shown in the illustration on the facing page.
Caution: Wires from the paper feed motor (J4) must not go over or near the top of the
MICR amplifier board or electromagnetic interference will result. Pull the cables taut and
clip them in the base clip.
2. Hold the MICR amplifier board with the blue pots on the top and reconnect the
connections from the MICR assembly to the MICR amplifier board as shown in the
illustration.
a. Read head to J1
b. Buckhead to J1
c. MICR solenoid to J3
d. Interconnect to J2 (from main board)
3. Replace the MICR amplifier board in the slot in the base by deflecting the board
forward and pushing down hard to snap it into place. The tab on back of the MICR
bracket lines up with the hole on the board.
4. Route the read head wire between the chip on the MICR board and the MICR bracket.
•
You may have to deflect the board forward to secure the wire.
•
Wires from the printer solenoid go behind the MICR amplifier board.
•
Thread the carriage motor wire through the clip on the back of the strain relief plate
(on top of the cantilever).
5. Route the interconnect harness through the cord keep on the back of the cantilever.
6. Check that the MICR read head is able to move smoothly by pushing down on the
torsion spring arm.
The read head should move up and down freely and should not catch on anything as it
moves up and down.
Refer to the illustration in “Removing the MICR Assembly from the Print Mechanism”
in chapter 11.