TM 55-1930-209-14&P-11
(5)
Disconnect cables (C3, C4, and 1 P14A) from bilge alarm module.
(6)
Disconnect cable (A8-1 and A8-2) to chlorination system metering pump control unit
(7)
Remove mounting hardware and carefully remove main processor.
b.
Installation
(1)
Install main processor In reverse order of installation in step a. See also Section I in PMS II 6050D
Installation Manual in Appendix B for additional installation information.
(2)
Operate monitoring system and check main processor for normal operation. If main processor does not
operate normally, troubleshoot as given in Section IX in PMS II Maintenance Manual in Appendix B.
4-7 Keyboard
WARNING
Make sure main power switch (Figure 1-3) Is In OFF position when performing maintenance.
Redtag switch with: "WARNING DO NOT ACTIVATE. REPAIRS BEING MADE."
4-7.1 Cleaning and Inspection
a.
Wipe clean exterior of keyboard with clean rag Remove front plate and inner cover. Vacuum clean or clean
inside with electrician's brush. Avoid using unauthorized solvents for cleaning inside of main processor.
Solvents leave a greasy film on components that may reduce electrical conductivity.
b.
Visually inspect for indications of burns, corrosion, loose connections, damaged parts, or chipped paint Clean
corrosion, tighten loose connections, and replace damaged parts. Remove corrosion with silver polish, fine
sandpaper, or burnishing tool. Do not use emery paper or emery cloth or steel wool. Vacuum to remove residue
Touch up paint according to TB 43-144. Do not paint threads or labels.
4-7.2 Test
a.
If keyboard is inoperative, move main power switch to ON (Figure 1-3). Check input voltage from main
processor If Input voltage reading Is not between 25 and 28 Vdc, go to step b to check main processor and cable.
If reading is between 25 and 28 Vdc, go to step c to check keyboard.
b.
Check main processor output voltage to keyboard If output voltage reading is not between 25 and 28 Vdc, main
processor is at fault Check main processor as given In paragraph 4-6. If output voltage reading is between 25
and 28 Vdc, check cable connections and continuity. Tighten cable connection or repair or replace bad cable
between main processor and keyboard
c.
Check keyboard output voltage to alarm relay module. If output voltage reading is not 25 to 28 Vdc, replace fuse
if bad as given In paragraph 4-7.3 or replace process and display board in main processor as given In paragraph
4-6.3. If after repair keyboard still does not operate, troubleshoot as given in Section IX in the PMS II
Maintenance Manual. If after troubleshooting keyboard still does not operate normally, replace video monitor as
given In paragraph 4-6.4.
4-7.3 Repair
4-7.3.1 Fuse replacement
CAUTION
When removing front of keyboard use care not to damage keyboard printed circuit board and
connecting cables.
a.
Remove front plate by loosening four screws on front of keyboard
b.
Remove cover protecting keyboard Inner circuitry by removing six nuts holding cover in place.
c.
Remove 3A fuse located on printed circuit board and replace.
d.
Remove Inner circuitry cover and front page.
4-5
