Fusereplacement - Keithley 177 Instruction Manual

4. To replace the knob, reverse the preceding steps. Do not
substitute any other knob. If the knob or its cap is lost or
damaged, order only Keithley part number KN-41-l as a
replacement.
Figure 5-3. F&t Panel Zero Knob Removal
5.8 FUSE REPLACEMENT
All fuses are located internally in the Model 177. To replace a
fuse, proceed as follows:
WARNING
Disconnect the line cord before removing
the caaa cover.
1, Turn off power and disconnect the line cord.
2. Turn the Model 177 bottom side up and loosen the four
screws in the bottom cover. These screws are held captive
by rubber O-rings.
3. Hold the top and bottom covars together to prevent their
separation and turn the Modal 177 over to normal position.
4.
Lift off the top covar.
CAUTION
Do not install fuses with higher ratings than
specified. Instrument damage may occur.
5. Replacement of battery pack fuse F301:
A. Leave the battery pack in place and connected.
B. Remove F301, shown in Figure 5-4, and replace it with
a ZA, 25OV. 3AG fuse (Keithley part number FU-131.
E&,\
1788,BATTERV
BAITERV FUSE F301
LINE FUSE FlOZ
\\ CONiUECTOR
\\
PACK
Figure 5.4. Battery Pack Installation
5-5