User manual

97
MC-III™ EXP Flow Analyzer Section 6
9. Remove the original circuit assembly from the enclosure.
10. Connect the ribbon cable of the keypad to the J3 connector on the LCD side of the circuit assembly as
follows:
a. Insert the end of the ribbon cable into the plastic clip.
b. While holding the ribbon cable in place, press the black plastic clip into the connector until it snaps.
11. Mount the circuit assembly to the keypad with the two #4-40 × 5/16” screws.
12. Reconnect the battery cable to J1 on the circuit assembly.
13. Reconnect all wiring to terminal blocks TB1, TB2 and TB3 (and J2, if applicable).
14. Mount the display/keypad assembly to the enclosure with the two #4-40 × 7/8” screws.
15. Recalibrate the MC-III EXP, then replace the enclosure cover.
16. Re-establish power to the peripheral circuitry.
Keypad Replacement
!
WARNING: To prevent ignition of hazardous atmospheres, do not remove the cover while
circuits are alive. Under normal conditions, the MC-III EXP poses no hazard when opened in a
safe area.
To replace the keypad of the MC-III EXP, perform the following steps:
1. Unscrew the cover of the enclosure counter-clockwise until it separates from the main body of the enclo-
sure.
2. Using a small standard blade screwdriver, remove the two #4-40 × 7/8” screws located to the right and
left side of the display.
3. Lift the display/keypad assembly from the enclosure.
4. Remove the two #4-40 × 5/16” screws fastening the circuit assembly to the keypad (Figure 6.5, page 96.
5. Disconnect the keypad ribbon cable from the J3 connector on the LCD side of the circuit assembly as fol-
lows:
a. Grasp the black clip between a thumb and forenger (see white arrows in Figure 6.6, page 96.
b. Squeeze both sides of the clip and gently pull to release the clip from the plastic connector that holds
it in place. DO NOT PULL on the ribbon cable. When the black plastic clip is properly disengaged,
the cable will release freely.
6. Remove the circuit assembly.
7. Connect the ribbon cable of the keypad to the J3 connector on the LCD side of the circuit assembly as
follows:
a. Insert the end of the ribbon cable into the plastic clip.
b. While holding the ribbon cable in place, press the black plastic clip into the connector until it snaps.
8. Mount the circuit assembly to the keypad with the two #4-40 × 5/16” screws.