ARMY TM 10-4610-309-14
MARINE CORPS TM10802A-14/1
0035 00
TACTICAL WATER PURIFICATION SYSTEM (TWPS)
TROUBLESHOOTING PROCEDURES
UNIT TROUBLESHOOTING - TWPS CONTROL SYSTEMS
Table 2. OCP Display and Instrument Loop Troubleshooting Continued.
ITEM
MALFUNCTION
POSSIBLE CAUSES
CORRECTIVE ACTION
9
Reject flow reading is not as
4)
Use the arrows to change the display to
cont.
expected from previous
20.00 mA.
operational data (continued).
5)
When the steps below are completed,
press MENU and then ESC to return to
the normal display screen.
PLC slot 11 input card or Flow Transmitter
Open the OCP display panel to expose the
FT-401 output failure (continued).
sub-panel. Locate the Slot 11 input card.
Open the wire way cover and locate terminal
IN4+. Remove the wire and turn the terminal
screw back in. Measure the mA (4-20mA)
between the terminal and the wire (WP
1) If the mA reading is 20 mA, and the flow
meter display does not read
approximately 50 gpm, replace the slot
11 input card (WP 0060).
2) If the mA reading is not 19.5 to 20.5,
replace the transmitter (WP 0062).
10
RO Feed Tank % Level reads
PLC Slot 9 output card failure or display
Conduct BIT test and stop at the display test.
0 with level in the tank, reads
failure.
If the display does not count up, refer to Item
a level other than actual by
2 above.
observation, or the reading
changes up and down rapidly.
Open the OCP display panel to expose the
Level transmitter LT-201 or PLC Slot 12
sub-panel. Locate the Slot 12 input card
input card failure, RO feed tank level high.
replace card.
1) Remove IN3+ wire and turn terminal
screw back in. Measure the mA (4-
20mA range) between the wire and the
terminal.
2) If reading is approximately 20mA,
perform continuity checks with PDP
main breaker OFF. Perform continuity
check on wiring from input card to
connector pins. Check for short circuit
between pins A and B with connector
disconnected from transducer and both
wires disconnected from input card.
Replace cable if short circuit found.
3) If short circuit not found, replace LT-
201.
4) If problem re-occurs replace Slot 12
input card.
Level transmitter LT-201 or PLC Slot 12
Open the OCP display panel to expose the
input card failure, RO feed tank level low.
sub-panel. Locate the Slot 12 input card
replace card.
1) Remove IN3+ wire and turn terminal
screw back in. Measure the mA (4-
20mA range) between the wire and the
terminal.
0035 00-11
