Front Panel Disassembly; Removing Power Components; Power Module Removal - Keithley 2425 Service Manual

Model 2425 Service Manual

Front panel disassembly

Use the following procedures to remove the display board and/or the pushbutton switch
pad:
1.
2.
3.
4.

Removing power components

The following procedures to remove the power supply and/or power module require that
the case cover and motherboard be removed, as previously explained.

Power module removal

Perform the following steps to remove the rear panel power module:
WARNING
1.
2.
3.
4.
Unplug the display board ribbon cables.
Remove front panel assembly.
This assembly has four retaining clips that snap onto the chassis over four pem nut
studs. Two retaining clips are located on each side of the front panel. Pull the
retaining clips outward and, at the same time, pull the front panel assembly for-
ward until it separates from the chassis.
Using a thin-bladed screwdriver, pry the plastic PC board stop (located at the bot-
tom of the display board) until the bar separates from the casing. Pull the display
board from the front panel.
Remove the switch pad by pulling it from the front panel.
To avoid electrical shock, which could result in injury or death, the
ground wire of the power module must be connected to chassis
ground. When installing the power module, be sure to re-connect the
green and yellow ground wire to the threaded stud on the chassis.
Remove the analog board.
Unplug the cable connecting the power module to the digital board.
Disconnect the power module's ground wire. This green and yellow wire connects
to a threaded stud on the chassis with a kep nut.
Squeeze the latches on either side of the power module while pushing the module
from the access hole.
Disassembly 5-7