13: Removing The Thermal Mechanism; Procedure - NCR 7194 Service Manual

4-22 Chapter 4: Servicing the Printer

13: Removing the Thermal Mechanism

Procedure

Assembly/disassembly procedure to service the Thermal Mechanism.
You must replace the entire mechanism if any individual part is faulty.
The Platen-Carrier Assembly (part of the Top Cover Assembly and
containing the Fixed Knife Blade) must be replaced whenever the
Thermal Mechanism (containing the Rotating Knife Blade) is replaced.
See "Removing the Platen/Fixed Knife Carrier Assembly" on page 13.
Tools: Pozidriv #1, #2
1. Open the Rear Cover and remove the paper from the printer.
2. Disconnect all the cables from the printer.
Caution: Electrostatic Discharge could damage the Control or
Options PC boards. Wear a grounded wrist strap and use a static mat
or other ESD protected work surface when handling electronic
components.
3. Remove the Top Cover Assembly by pushing the two tabs at the
rear of the paper bucket towards the back with a flat-blade
screwdriver. (See page 16.)
4. Access the Control PC Board.
a. Place the printer on its front with the bottom facing you.
b. Remove the screw in the Base Plate.
c. Swing the right side of the Base Plate towards you and to the
right to release it from the tabs in the cabinet. Lower Base Plate
onto a flat surface.
5. Disconnect all wires from the Control PC Board.
Note: For ease of installation, it is quicker to disconnect all the wires,
even though not all wires need to be disconnected for Thermal
Mechanism replacement.