Keithley 2700, Service Manual

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3-2 Routine Maintenance
Introduction
The information in this section deals with routine type maintenance and includes procedures
for setting the line voltage, replacing the Model 2700 line and front terminal AMPS fuses, and
replacing the amps fuses for the Models 7700 and 7702 plug-in modules. Replacement of the
Model 2700 non-volatile RAM battery is also covered.
Setting the line voltage and replacing the line fuse
WARNING Disconnect the line cord at the rear panel, and remove all test leads con-
nected to the instrument (front and rear) before replacing the line fuse.
The power line fuse is located in the power module next to the AC power receptacle (see
Figure 3-1 ). If the line voltage must be changed, or if the line fuse requires replacement, per-
form the following steps:
1. Place the tip of a flat-blade screwdriver into the power module by the fuse holder
assembly (see
Figure 3-1 ). Gently push in and to the left. Release pressure on the
assembly, and its internal spring will push it out of the power module.
2. Remove the fuse, and replace it with the type listed in Table 3-1 .
CAUTION For continued protection against fire or instrument damage, replace the
fuse only with the type and rating listed. If the instrument repeatedly
blows fuses, locate and correct the cause of the trouble before replacing the
fuse.
3. If configuring the instrument for a different line voltage, remove the line voltage selec-
tor from the assembly, and rotate it to the proper position. When the selector is installed
into the fuse holder assembly, the correct line voltage appears inverted in the window.
CAUTION Operating the Model 2700 on the wrong line voltage may result in instru-
ment damage.
4. Install the fuse holder assembly into the power module by pushing it in until it locks in
place.