Keithley 2010, Service Manual, Page: 79 / 134

Remove all the connections except the front AMPS connection by pulling the wires off the
pin connectors. To remove the front panel AMPS input wire (white), first remove the AMPS fuse
holder, and then use needle-nose pliers to grasp the AMP wire near fuse housing. Push the wire
forward and down to snap the spring out of the fuse housing. Carefully pull the spring and
contact tip out of housing.
During re-assembly, use the following table to identify input terminals:
4. Unplug cables:
• Unplug the display board ribbon cable from connector J1014.
• Unplug the transformer cables from connectors J1016 and J1015.
• Unplug the OPTION SLOT ribbon cable from connector J1017.
5. Remove the fastening screw that secures the main PC board to the chassis. This screw is
located along the left side of the unit towards the rear. It also holds down U144.
During re-assembly, replace the board, and start the IEEE-488 and RS-232 connector
nuts and the mounting screw. Tighten all the fasteners once they are all in place and the
board is correctly aligned.
6. Remove the motherboard, which is held in place by edge guides on each side, by sliding
it forward until the board edges clear the guides. Carefully pull the motherboard from
the chassis.
Front panel disassembly
Use the following procedures to remove the display board and/or the pushbutton switch pad:
NOTE You must first remove the case cover, the front/rear input switch, and the front input
terminal wires as described in earlier in this section.
1. Unplug the display board ribbon cable from connector J1014.
2. Remove the 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 forward until it separates
from the chassis.
Input terminals Front wire color Rear wire color
INPUT HI
INPUT LO
SENSE HI
SENSE LO
AMPS Red
Black
Yellow
Gray
White White/Red
White/Black
White/Yellow
White/Gray
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5-6 Disassembly