Maintenance
11.5 ASSEMBLY REPLACEMENT
The following describes replacement of the controller's assemblies. The subsections below are organized in the
sequence of controller disassembly and reassembly. Most subsections have Removal and Installation paragraphs.
Controller disassembly is described by the Removal paragraphs and controller assembly is described by the
Installations paragraphs.
TOOLS:
Common hand tools for electronic equipment servicing are needed and a torque screwdriver, calibrated in
inch-pounds, is recommended. Before handling an assembly, refer to Section 11.2.4 for electrostatic
discharge prevention procedures. See Figure 11-1 for an exploded view of the controller that shows field
replaceable assemblies and individual parts.
JUMPERS:
There are three jumpers on the MPU Controller board: W2, W4, and either W7 or W8. Their settings are described
in the following sections and shown in Figures 11-2 and 11-3.
FIELD UPGRADES:
The procedures below are provided for servicing an assembled controller. When installing a circuit board in the
controller to add or change performance features, always refer to the Kit Installation Instruction supplied in the
circuit board kit for details specific to the supplied board.
11.5.1 Fuse
A power input fuse is located on the MPU Controller board as shown in Figure 11-1. This is the controller's power
input fuse. A replacement fuse can be obtained from a local electronics supplier or can be ordered from the factory.
See the Parts List for fuse part number and description.
To replace the fuse:
1. Refer to section 11.5.2 and remove the Display Assembly
2. Refer to Section 11.5.3 and remove the MPU Controller board.
3. While the controller is apart, visually inspect the assemblies for overheated or otherwise damaged components.
4. Remove the failed fuse and install a replacement.
5. Reassemble the controller. Refer to the above referenced sections as necessary.
6. Apply power to the controller. Operate the controller off-line for several minutes to be sure that a condition
does not exist that will cause the replacement fuse to fail.
11.5.2 Display Assembly
To replace a Display Assembly, see Section 11.5.2.1. To replace the bezel or the circuit board, perform the
procedures in Sections 11.5.2.1 and 11.5.2.2.
11.5.2.1 To Replace a Display Assembly
REMOVAL:
1. In a hazardous area, remove power from the Controller.
2. Protect the station's electronic components from electrostatic discharge. Fasten a conductive wrist
strap around your wrist and ground the strap to the ground screw on the Controller's case, an
unpainted area on the panel, or a grounded static dissipative workmat.
11-12
UM353-1
March 2003