Fluke 289 - Basic Maintenance; Opening the Meter Case; Removing and Reinserting the Printed Circuit Assembly (PCA)

True-rms Digital Multimeters
Basic Maintenance
11
Basic Maintenance
XW Warning
To avoid electrical shock or personal injury, remove the test
leads and any input signals before opening the case or
replacing the battery or fuses. To prevent damage or injury,
install ONLY batteries or fuses specified for this product.
Opening the Meter Case
W Caution
To avoid unintended circuit shorting, always place the
uncovered Meter assembly on a protective surface. When the
case of the Meter is open, circuit connections are exposed.
To open the Meter case, do the following:
1. Disconnect test leads from any live source, turn the Meter off, and remove the test
leads from the input terminals.
2. Use a flat-blade screwdriver to turn the battery door fastener counterclockwise until
the arrow points to unlock position.
3. Lift up on the bottom of the battery pack and slide down to remove as shown in
Figure 2.
4. The case bottom is secured to the case top by six screws. Remove the screws with a
Phillips-head screwdriver.
5. Pull the two halves of the case apart.
Removing and Reinserting the Printed Circuit Assembly
The circuit board assembly (PCA) must be removed to access and replace the LCD.
Refer to Figure 5 while performing the following procedure.
W Caution
The PCA is extremely susceptible to contamination. Handle it
by the fuse clips or edges of the PCA only. Use clean surgical
gloves to help avoid contamination.
The LCD cable is very delicate. Use extreme caution and do not
exert excess force or strain on the cable or mating connector
when removing.
1. Put the Meter’s rotary switch knob in the N position.
2. Refer to the “Opening the Meter Case” section and remove the case bottom to access
the PCA.
3. Remove six Phillips-head screws securing the PCA to the case top and input
terminals.
4. Remove the bottom shield.
5. Before lifting out the PCA, very carefully remove the fragile LCD cable from the
LCD connector without excessive bending of the cable or connector. Remove the
PCA.
6. Remove the top shield.
7. The LCD is now accessible and may be removed easily.